MUFF WIGGLER Forum Index
 FAQ & Terms of UseFAQ & Terms Of Use   Wiggler RadioMW Radio   Muff Wiggler TwitterTwitter   Support the site @ PatreonPatreon 
 SearchSearch   RegisterSign up   Log inLog in 
WIGGLING 'LITE' IN GUEST MODE

The Phonic Taxidermist
MUFF WIGGLER Forum Index -> Music Tech DIY  
Author The Phonic Taxidermist
Crashlander42
Has anyone seen this?

The Phonic Taxidermist on circuitbenders.CO.UK. It's a clone of the Maplin Voice Vandal, which I'm unfamiliar with.

Looks super interesting to me. It would be pretty simple to put behind a panel.
Bamboombaps
I'd been waiting for this thanks for the heads up
ClausF
I'm in their email list and ordered yesterday... Guinness ftw!
Crashlander42
ClausF wrote:
I'm in their email list and ordered yesterday... Guinness ftw!



Same here. I ordered one as soon as I saw it.
windspirit
So its basically a ring mod mixed with a delay?
Crashlander42
It calls it a chopper, but it does sound ringmodish. Looking at the schematic I'm not entirely sure how the band selection switches work, but the chopper looks like it's just running the signal through a CMOS counter.

The delay on it sounds nice though. It'd be nice to have a delay in my system that isn't a PT2339

av500
Crashlander42 wrote:
It calls it a chopper, but it does sound ringmodish. Looking at the schematic I'm not entirely sure how the band selection switches work, but the chopper looks like it's just running the signal through a CMOS counter.

The delay on it sounds nice though. It'd be nice to have a delay in my system that isn't a PT2339



original schematics here:

http://www.mediafire.com/download/a9dgz3gzxje/voicevandal.zip
Crashlander42
av500 wrote:


original schematics here:

http://www.mediafire.com/download/a9dgz3gzxje/voicevandal.zip


Excellent! Thanks! That's a much better explanation.
sammy123
Cool i ordered one as well. If anyone comes up with a panel design please share. thumbs up
Barcode
I ordered one also. It looks like it could be loads of fun.
cane creek
ill order one once they get some chips in.
Zaibach
I also ordered one today. The HT8955A delay chip is available at

http://uk-electronic.de/onlineshop/product_info.php?products_id=1016&o sCsid=8831693374990f692d6f949f5027eb9e

for 6,95€, and I just ordered the RAM at ebay. Ready to go once the board arrives! hyper
Crashlander42
They still had the chips when I ordered yesterday. For any US people Smallbear has the chips in stock too.
DJBRUTAL
OK, so how do we go about adding CV to this?
Barcode
DJBRUTAL wrote:
OK, so how do we go about adding CV to this?


Vactrols!
MacSynth
Barcode wrote:
DJBRUTAL wrote:
OK, so how do we go about adding CV to this?


Vactrols!

Easy solution: http://store.synthrotek.com/Vac_Pak_PCB
xahdrez
Ordered this yesterday at lunch time - just arrived! Super fast!

This is fun!

Also interested in a panel if anyone is making one!
oberkorn
ordered one as well
MacSynth
What of the parameters would you make CV-controlled? As I have two VacPak-PCBs I have to make a decision sooner or later.
e-tekk
hey there, i ordered most of the parts for the build, but where can i get the right potentiometers in the EU, especially the 470k and the dual b100k pot? Any ideas for a noob?

greetz
enrico
MacSynth
e-tekk wrote:
hey there, i ordered most of the parts for the build, but where can i get the right potentiometers in the EU, especially the 470k and the dual b100k pot? Any ideas for a noob?

greetz
enrico

Musikding.de has dual potentiometers that have the right value, but they are not for PCB-mounting. A 500k would work as well, if you can't find 470k. There is always mouser.de

I can't wait until the PCB arrives!
Eloc
e-tekk wrote:
hey there, i ordered most of the parts for the build, but where can i get the right potentiometers in the EU, especially the 470k and the dual b100k pot? Any ideas for a noob?

greetz
enrico


500K may be easier to find than 470K, which I imagine would work fine. I personally like bitsbox.co.uk, they have a good selection of pots.

MacSynth wrote:
What of the parameters would you make CV-controlled? As I have two VacPak-PCBs I have to make a decision sooner or later.


I would think VR1 and VR4 (chopper pitch and echo rate). Also, it would be worth experimenting with replacing R31 with a pot, because this is actually effectively a sample rate control for the delay chip, and so you might be able to get some interesting grungy bit reduction stuff going on with that, just to add to the distortion.
e-tekk
thanks guys. i thought about a 500k, but wasn´t shure if it works. i found a dual pot via mouser, but they sell them only in a package of 1000 pieces. a bit too much for this pcb... maybe these here will do it?

http://www.musikding.de/CTR-Poti-16mm-Stereo-100k-lin
MacSynth
e-tekk wrote:
thanks guys. i thought about a 500k, but wasn´t shure if it works. i found a dual pot via mouser, but they sell them only in a package of 1000 pieces. a bit too much for this pcb... maybe these here will do it?

http://www.musikding.de/CTR-Poti-16mm-Stereo-100k-lin

Try this:
Banzai
e-tekk
thank you!
cane creek
e-tekk wrote:
hey there, i ordered most of the parts for the build, but where can i get the right potentiometers in the EU, especially the 470k and the dual b100k pot? Any ideas for a noob?

greetz
enrico


Forget EU, use Tayda.

and here's 15% Discount Coupon Code : "15HOPS"
crustypaul
Afternoon all, Paul from circuitbenders here. ;-)

Unfortunately it seems that there might be a bit of a problem with some of the HT8955A delay chips we've sent out in some of the PCB & IC bundles.

It looks like the load of HT8955A chips that we had came from two batches, ones labelled 1427C, and another batch labelled A404G1421. Annoyingly we didn't realise they were different batches and don't know what the proportions of each type were, but it seems that the random tests we did may have all been on 1427C ones as they all worked fine.
For some bizarre reason the ones labelled A404G1421 seem to have a ridiculous amount of feedback, to the point where you can't get below about 6 or 7 repeats and with VR3 set any higher than about 12 o clock the delay starts to self oscillate wildly. They're also a fair bit noisier than the 1427C ones.

I'd suggest that you socket the RAM and the HT8955A anyway, but if you've bought the IC bundle and you have a A404G1421 chip, give it a try. If its got a massive amount of uncontrollable feedback send us an email and we'll sort something out.

Apologies if you've got a dubious IC. I have no idea why this specific batch seem to be acting differently.
e-tekk
Try this:
Banzai

i got these knobs today, but the pins won´t fit the holes on the pcb. they are too small. daammn... i payed 4 euros for this one. can anyone recommend the right ones. help

greetz
enrico
av500
e-tekk wrote:
Try this:
Banzai

i got these knobs today, but the pins won´t fit the holes on the pcb. they are too small. daammn... i payed 4 euros for this one. can anyone recommend the right ones. help

greetz
enrico


looks like the PCB takes 16mm pots and you bought 12mm ones.
crustypaul
Apologies for any confusion. Using 500K pots in place of the 470K ones is perfectly ok.
I've never been entirely sure why European pots are always 47K and 470K compared to 50K and 500K everywhere else, but it won't make any difference.

The board uses standard 16MM pots. The 12mm ones someone recommended from Banzai won't fit into the PCB. The easiest place to get the right pots is Tayda, but theres plenty of other places.

Heres a video someone made of the frequency pot being controlled via CV with a vactrol. The Phonic Taxidermist is the thing with the blue knobs at the back.
I'm not 100% sure whats going on there, but i'm told it works fine.
spotta
Got mine, Is anyone thinking of doing a panel?
e-tekk
i made me one, but couldn´t test it yet if it´s working, because i don´t have all the parts together. i can upload an illustrator file if needed.

spotta
e-tekk wrote:
i made me one, but couldn´t test it yet if it´s working, because i don´t have all the parts together. i can upload an illustrator file if needed.


That would be cool if you could, panel making is something I need to get into, and have been meaning to for a while,
my Illustrator skills are not great, but I can move some text around and fit in another jack socket etc.
Thanks.
e-tekk
i will do it friday. i am at home now and the files are on the pc at work. i can also upload a cad-file, dwg or dxf, if it helps you more. wich illustrator version do you need?
EATyourGUITAR
this was done by death by audio first after it was discoverd in a childs toy. maybe 4 or 5 years ago. it is unclear what role maplin played in all of this since I do not know when they started selling these kits.

here is an old thread http://www.diystompboxes.com/smfforum/index.php?topic=108078.0

and here is the guitar pedal in question
spotta
an .ai for CS6 will be perfect. Thank you.
sammy123
Can .ai be easily converted to .svg? I use Inkscape since it's free.
Barcode
e-tekk... would you mind if I borrow your layout? I'm planning on doing a PCB panel in the next couple days.
Bamboombaps
cool Barcode is on the case. I'll hold on Guinness ftw!
SoundPool
EATyourGUITAR wrote:
this was done by death by audio first after it was discoverd in a childs toy. maybe 4 or 5 years ago. it is unclear what role maplin played in all of this since I do not know when they started selling these kits.

here is an old thread http://www.diystompboxes.com/smfforum/index.php?topic=108078.0

and here is the guitar pedal in question


I think this is a totally different circuit. This is basically the kit Maplin still sells which is based on HT8950 voice processor not HT8955 which is an echo chip that also requires an additional RAM chip
Barcode
I decided to go with 10hp since I dislike having the PCB so close to the edge of the panel. Here's the start of my design.

I plan on doing the panel in yellow to match the PCB from cb.

e-tekk
Barcode wrote:
e-tekk... would you mind if I borrow your layout? I'm planning on doing a PCB panel in the next couple days.


no problem...
e-tekk
sammy123 wrote:
Can .ai be easily converted to .svg? I use Inkscape since it's free.


i think it shouldn´t be a problem. i´ll upload the files tomorrow.
Barcode
Here's my near final panel. This one is designed for 1/2" or 12.7mm knobs (Davies). If anyone is interested in one please let me know. Send a PM.

Zaibach
Just designing my own panel.... Looks surprisingly similar to the ones alredy posted (saw them only after I sketched my layout) cool Then again, there aren't too many possibilities if you mount the pots on the pcb. But I will ditch the Mic/Line switch, I'm using my preamp to get my mic to the appropriate level, and I am adding the delay switch, which I find kind of useful for just the distortion effect. Is anyone implementing voltage control over one of the parameters? I think cv over delay time would be rad...
e-tekk
Here are the Illustrator CS6 file and the converted SVG file.
crustypaul
For anyone sourcing parts for this build, HT8955A's with the batch code A404G1421 DO NOT WORK properly.
They give the appearance of working, but theres far too much delay feedback, so its impossible get get below around 6 repeats. With VR3 set at anything over 12'o'clock or so, the feedback is completely uncontrollable.

I've put together a video showing a working chip, in this case a 1427C, and then a A404G1421 one.



You can kind of get a A404G1421 chip working by replacing R30 with 680K and VR3 with a C1M pot to lower the feedback a bit, but it still doesn't sound right.

A lot of Chinese sellers seem to be shipping A404G1421 chips cheap at the moment. They do look genuine, so i guess there must have been a massive quality control failure on that batch, and whoever is producing them just sold them off cheaply as a job lot.
SoundPool
anyone been doing standalone builds and manage to squeeze this in a pedal enclosure?

Found this case which looks like it should be ideal for wiring the switches/pots from the top more like a pedal/desktop unit- PCB should sit in there perfectly.
http://www.aliexpress.com/item/1-piece-30-105-100mm-1-18-4-13-3-94inch -aluminum-oem-cabinet/1249283417.html?spm=2114.01010208.3.175.QFEv4y&w s_ab_test=searchweb201556_0,searchweb201602_2_10037_10017_10034_10021_ 507_10022_10032_10020_10018_10019,searchweb201603_7&btsid=d09dd25d-955 2-4d01-b46e-9ea84f5f0c22
Zaibach
Just finished my build this afternoon... A whole lot of fun, this! cool


Also, FYI: My HT8995A has the batch code 0514K0213 and is working properly.
Bamboombaps
e-tekk wrote:
Here are the Illustrator CS6 file and the converted SVG file.


did anyone test this spacing for board mounted pots? i prefer the look of this one to barcodes one
e-tekk
Bamboombaps wrote:
e-tekk wrote:
Here are the Illustrator CS6 file and the converted SVG file.


did anyone test this spacing for board mounted pots? i prefer the look of this one to barcodes one


i made it after the dimensions on the http://www.circuitbenders.co.uk/forsale/phonictaxi/ptaxi.html site and it should work, but try it with a cardboard panel first.
Eloc
crustypaul wrote:
...It looks like the load of HT8955A chips that we had came from two batches, ones labelled 1427C, and another batch labelled A404G1421. Annoyingly we didn't realise they were different batches and don't know what the proportions of each type were, but it seems that the random tests we did may have all been on 1427C ones as they all worked fine.
For some bizarre reason the ones labelled A404G1421 seem to have a ridiculous amount of feedback, to the point where you can't get below about 6 or 7 repeats and with VR3 set any higher than about 12 o clock the delay starts to self oscillate wildly. They're also a fair bit noisier than the 1427C ones...


I bought a few of these chips with the intention of building a little delay module with them, and the ones I've received are the A404G1421 code... typically.

I'm trying to figure out if there is a solution to using the chips with this code successfully, and seen as the feedback amount looks to simply be a function of external resistors and isn't done internally at all, the only conclusion that I can come to is that the the output of these chips is far 'hotter'/greater in amplitude than the 1427C ones.

If the A404G1421 output is hotter than the 1427C, but crucially isn't distorted significantly then it should be a simple enough fix.

The distortion on the demo video of the two chips could be the output op-amp clipping if it is expecting a much smaller signal and thus has quite a high gain, rather than the chip itself distorting. The greater gain of these chips would also explain the increased noise, but again may disappear if the output signal is processed accordingly.
Bamboombaps
Ok so built this last night but when I power on a get nothing , then a slowish oscillation building up to a full on buzz that no combo of switches or input can remove. Does this point to anything glaringly obvious?
crustypaul
Eloc wrote:

I'm trying to figure out if there is a solution to using the chips with this code successfully, and seen as the feedback amount looks to simply be a function of external resistors and isn't done internally at all, the only conclusion that I can come to is that the the output of these chips is far 'hotter'/greater in amplitude than the 1427C ones.

If the A404G1421 output is hotter than the 1427C, but crucially isn't distorted significantly then it should be a simple enough fix.


You can kind of get the feedback down to a more workable range by putting more resistance in the return path. On the Phonic taxidermist sticking in a 680K resistor and using a 1M pot, rather than the 100K resistor and 470K pot on the schematic, kind of gets it into usable territory, but it still doesn't sound right. Each repeat has a slight halo of distortion and you you don't get nearly as nice an EQ change on each repeat as you do with a working chip.
spotta
crustypaul wrote:
Afternoon all, Paul from circuitbenders here. ;-)

Unfortunately it seems that there might be a bit of a problem with some of the HT8955A delay chips we've sent out in some of the PCB & IC bundles.

It looks like the load of HT8955A chips that we had came from two batches, ones labelled 1427C, and another batch labelled A404G1421. Annoyingly we didn't realise they were different batches and don't know what the proportions of each type were, but it seems that the random tests we did may have all been on 1427C ones as they all worked fine.
For some bizarre reason the ones labelled A404G1421 seem to have a ridiculous amount of feedback, to the point where you can't get below about 6 or 7 repeats and with VR3 set any higher than about 12 o clock the delay starts to self oscillate wildly. They're also a fair bit noisier than the 1427C ones.

The code on mine (bought elsewhere as you had no stock at the time) says 1108S1121. I'm still building and waiting for a few parts, but will let you know if it works and share the source if it does.
spotta
Eloc wrote:
Also, it would be worth experimenting with replacing R31 with a pot, because this is actually effectively a sample rate control for the delay chip, and so you might be able to get some interesting grungy bit reduction stuff going on with that, just to add to the distortion.

Has anyone tried this yet? sounds interesting
Bamboombaps
Here's my wierd attempt https://youtu.be/gtpJ4By6rFE

Any ideas?
crustypaul
Bamboombaps wrote:

Any ideas?


Yes, by the look of it you've got both opamps in the wrong way round.
tokyomatik
I have a couple of these PCBs and I started populating....
in the while i was wondering if it would be possible to clock it externally
any idea?

I would also like to control at least delay rate and frequency and the vac pak looks like a quick solution
but another interesting thing would be replace or integrate the frequency band switches with an electronic swith, a bit like the Schippmann CS-8 vcf , where you can "trigger" the various modes individually

http://www.schippmann-music.com/downloads/CS8_VCF-02_Man10_ENG.pdf

or the circuit that Fonitronik designed for his gate controlled LPG

http://www.fonik.de/Page48.html#Link386

well....all these features would make this thing really funny to play with....
Bamboombaps
crustypaul wrote:
Bamboombaps wrote:

Any ideas?


Yes, by the look of it you've got both opamps in the wrong way round.


MY ASS IS BLEEDING

Sorted. I do think I'm having the IC issue though. It's out of control at times.

EDIT- RECEIVED MY REPLACEMENT IC TODAY THANKS PAUL !
tokyomatik
so? any one can confirm me if I can add a simple flip flop to integrate with the toggle switches so that i could use gates or triggers to select the frequency band?
mcop
I'm intending to try replacing the switches with another 4066 and going to play with controling that with gates or even something like a 4024 or 4516. When is going to depend on what batch my delay chip is when it arrives of course! Will share anything useful I come up with.
tokyomatik
mcop wrote:
I'm intending to try replacing the switches with another 4066 and going to play with controling that with gates or even something like a 4024 or 4516. When is going to depend on what batch my delay chip is when it arrives of course! Will share anything useful I come up with.

applause applause we're not worthy we're not worthy we're not worthy we're not worthy we're not worthy we're not worthy we're not worthy
e-tekk
hey guys, i build my the taxidermist yesterday and i can´t get this thing to work right. i got the replacement delay chip from paul over the weekend and put all things together. here is what works correctly...

- all frequency band switches are working
- in and out with the change of mic and line works
- the distortion also works (sounds great btw)

what not works is the delay part and the power led. both pots for frequency and delay time are doing nothing. i replaced the delay chip with another, but still no delay sound. do i have to connect the delay jump holes with a jumper or bridge them somehow? maybe i answered my own question here, because i looked at the pot grounding picture in the build manual and saw these holes were connected?? here is a picture... thanks for any help in advance!

enrico

crustypaul
e-tekk wrote:

what not works is the delay part and the power led. both pots for frequency and delay time are doing nothing


I think your first problem is that the delay section isn't getting any power because you've left out the regulator at REG2. This supplies the 5v for the delay section and the power LED.

You need to connect a piece of wire across 'DELAY JUMP' if you want to hear the delay sound, as this is the return path for the delay echos. Its an optional jumper so that you can wire a switch across it if you'd prefer to switch the delay echos on and off completely.
e-tekk
Thank you paul! My understanding was that, if i power it from a eurorack system, i only need to fill the REG1. My thoughts about the delay jump were also wrong... Thanks for clearing this up for me! I learn a lot here. I think i will replace the mic-line switch with a switch for the delay on and off. This seems to make a bit more sense for my needs. Don´t need the mic input as much as an delay on | off switch i think.

Many thanks thumbs up
crustypaul
We were planning on offering a load more PCB and IC bundles on the circuitbenders site this week when a new batch of HT8955A'a arrived, but having just looked at whats arrived, something a bit weird has happened.

Previously we'd bought 40 HT8955A's from a seller on aliexpress, and they sent chips with the batch code of just 1427C, which worked perfectly. As they initially sent working chips i bought 100 more from them, and made a point of specifying with the order that i wanted exactly the same 1427C chips that i'd been sent before, and were shown in the photo on the listing.

About a hour ago they arrived. All of them are labelled A404G1427C, and none of them work properly.

I'm not 100% sure whats going on here. It seems that no HT8955A with a batch code starting with A404 actually works, but i do get the impression that they've got these chips printed specifically for my order! For a start, the Holtek logo is slightly more angled and squashed on these chips compared to working ones. Its as if its been copied..... badly.

I'm giving up on trying to offer IC and PCB bundles. Its costing us WAY to much money! very frustrating
e-tekk
Thanks again Paul. Now all is working as it should be. I got three different chips here and only one is working. Its the chip with 127c written on it. I got a chip from a german seller and this one is totally crap and not useful. That thing distorts all the way without any signal plugged in. Seems to be a lot of defective chips out there. I hope you can work out your frustrating chip disaster.

greetz
enrico
e-tekk
e-tekk wrote:
Thanks again Paul. Now all is working as it should be. I got three different chips here and only one is working. Its the chip with 1427c written on it. I got a chip from a german seller and this one is totally crap and not useful. That thing distorts all the way without any signal plugged in. Seems to be a lot of defective chips out there. I hope you can work out your frustrating chip disaster.

greetz
enrico
Starspawn
Got mine running, can confirm that tayde opamps are crap and that you really need to ground at least the feedback pot.
Sounds nice mostly, but theres a lot of bleed from the frequency oscillator, I can pretty much mix it in and its constant.
Only other thing I did was use some (good) Tl072s instead of crap tayda 358.
Hmm and looking at the schematic the 4060 and 66 is N, mine are BE (buffered) so maybe a clue?
Starspawn
Some troubleshooting later the blame lies almost entirely on the leaking battery that was in my monotribe contaminating ground.
Little bit of noise sure, but entirely livable and expected level, and the OD and chopper section does indeed sound great.

Good job, and thanks for the kit, the quick replacement IC and go get any that are left guys wink

It's peanut butter jelly time!
Barcode
To anyone who was interested in my panel..... They arrived yesterday and turned out better than I expected. I plan to finish wiring mine up tonight then I will post some pictures.
sammy123
Barcode, I'd definitely like a panel if you have an extra.
Barcode
Here is the panel. Yellow with silver text. It's kinda hard to see with the light but I think it looks great. Folks who contacted me about the panel expect a pm in the next day or so.
xahdrez
Also interested in a panel if you still have any thumbs up
crustypaul
Barcode wrote:
Here is the panel. Yellow with silver text. It's kinda hard to see with the light but I think it looks great. Folks who contacted me about the panel expect a pm in the next day or so.


Excellent work! eek!

Just stole this an posted it on the circuitbenders.co.uk Facebook page.
http://tinyurl.com/h2vl3l4
tokyomatik
I almost finished to build mine and for now, to test it, I will keep it as defoult, but I still thinking about implementing cv control on frequency and delay rate, then the interesting would be to automate the freq band selection.
Somebody can be so kind to point me a basic circuit to use a 4046 or similar to replace the toggle switches, I would like to be able to trigger the 4 bands.....I'm sure is doable...is just a problem for a bginner like me.....

anybody??


have a nice day


peace

r
spotta
Panel arrived today Matt - looks great!

Quick question, Are the frequency solder points nearest C13 the Low ones or the High ones?
crustypaul
spotta wrote:

Quick question, Are the frequency solder points nearest C13 the Low ones or the High ones?


The lowest frequency one is on the right, and the high frequency on the left nearest to C13
crustypaul
tokyomatik wrote:

Somebody can be so kind to point me a basic circuit to use a 4046 or similar to replace the toggle switches, I would like to be able to trigger the 4 bands.....I'm sure is doable...is just a problem for a bginner like me.....
r


I think you mean a 4066, not a 4046.
Take a look at the pinout or datasheet for the 4066. They're fairly self explanatory.


Take pin 6 high and it closes a switch across pins 8 and 9. Pin 13 controls the switch across pins 1 and 2 etc.
If you wire the 4066 switches across the frequency band switch points it'll probably work ok.
spotta
crustypaul wrote:
spotta wrote:

Quick question, Are the frequency solder points nearest C13 the Low ones or the High ones?


The lowest frequency one is on the right, and the high frequency on the left nearest to C13

Ta!
tokyomatik
crustypaul wrote:
tokyomatik wrote:

Somebody can be so kind to point me a basic circuit to use a 4046 or similar to replace the toggle switches, I would like to be able to trigger the 4 bands.....I'm sure is doable...is just a problem for a bginner like me.....
r


I think you mean a 4066, not a 4046.
Take a look at the pinout or datasheet for the 4066. They're fairly self explanatory.


Take pin 6 high and it closes a switch across pins 8 and 9. Pin 13 controls the switch across pins 1 and 2 etc.
If you wire the 4066 switches across the frequency band switch points it'll probably work ok.

Ups! Yes I was meaning a 4066......
my question was kind of incomplete.......Can I send triggers or gates to the control pins of the 4066, without attenuation?
tokyomatik
Ok, finally I finished mine and the "ring modulator" section works, then I switch on the delay and is super noisy,also with feedback completely close!
the delay rate is doing something, i can hear it going but is completely covered by the noise, if i open the feedback just get more white noise.....
also without any input !!

i bought my HT8955A chips on ebay from adeleparts2010, chinese seller..... they have this code: 1108S1121.
also got the memories on ebay but from a german seller,
they are KM41C256P -7

wich one could be the problem??
Eloc
tokyomatik wrote:

Ups! Yes I was meaning a 4066......
my question was kind of incomplete.......Can I send triggers or gates to the control pins of the 4066, without attenuation?


CD4xxx inputs should be able to take any signal up to the power rail voltage, but you want to avoid negative voltages. Best to put something like an op-amp set up as a comparator followed by a diode in front of the control pin to be safe.
tokyomatik
spotta wrote:
crustypaul wrote:
Afternoon all, Paul from circuitbenders here. ;-)

Unfortunately it seems that there might be a bit of a problem with some of the HT8955A delay chips we've sent out in some of the PCB & IC bundles.

It looks like the load of HT8955A chips that we had came from two batches, ones labelled 1427C, and another batch labelled A404G1421. Annoyingly we didn't realise they were different batches and don't know what the proportions of each type were, but it seems that the random tests we did may have all been on 1427C ones as they all worked fine.
For some bizarre reason the ones labelled A404G1421 seem to have a ridiculous amount of feedback, to the point where you can't get below about 6 or 7 repeats and with VR3 set any higher than about 12 o clock the delay starts to self oscillate wildly. They're also a fair bit noisier than the 1427C ones.


The code on mine (bought elsewhere as you had no stock at the time) says 1108S1121. I'm still building and waiting for a few parts, but will let you know if it works and share the source if it does.



looks like we got the ICs fom the same batch, is yours working correctly ??
crustypaul
tokyomatik wrote:

i bought my HT8955A chips on ebay from adeleparts2010, chinese seller..... they have this code: 1108S1121.


I think the lesson to be learned here is to not buy suspiciously cheap IC's from China when you don't know exactly what you're getting!

I emailed Holtek about the HT8955A, and they told me that the last batch that they made was in 2004-2005, but most genuine chips will have a late 90's date code. I did have a working batch with a 2014 date codes though, so i guess its just pure luck whether a fake or refurbished chip will work.

An HT8955A with the code 1108S1121 was supposedly made in 2011, so it cannot be new or genuine, although inevitably the image on the chip of the listing you bought from shows a 1997 coded chip.

Heres an image of what i think is an original HT8955A from 1997 on the top, and a new refurbished/fake one i received from china at the bottom. Note the way the bottom one has a different font and text colour, and has the batch code in the wrong order. It also has very shallow indentations which are matt at the bottom, unlike the real one that has deep indentations with a polished bottom. I assume this is because the refurbished/fake one has had its top surface ground off and then has been 'blacktopped' so it can be reprinted. You can see how blatant this is if you look at the end of the chips. The blacktopped one on the right has a very dubious shape to its top half.

spotta
tokyomatik wrote:
spotta wrote:
crustypaul wrote:
Afternoon all, Paul from circuitbenders here. ;-)

Unfortunately it seems that there might be a bit of a problem with some of the HT8955A delay chips we've sent out in some of the PCB & IC bundles.

It looks like the load of HT8955A chips that we had came from two batches, ones labelled 1427C, and another batch labelled A404G1421. Annoyingly we didn't realise they were different batches and don't know what the proportions of each type were, but it seems that the random tests we did may have all been on 1427C ones as they all worked fine.
For some bizarre reason the ones labelled A404G1421 seem to have a ridiculous amount of feedback, to the point where you can't get below about 6 or 7 repeats and with VR3 set any higher than about 12 o clock the delay starts to self oscillate wildly. They're also a fair bit noisier than the 1427C ones.


The code on mine (bought elsewhere as you had no stock at the time) says 1108S1121. I'm still building and waiting for a few parts, but will let you know if it works and share the source if it does.



looks like we got the ICs fom the same batch, is yours working correctly ??

Seems to be, no harsh noise or anything like you mentioned, I only had 5 mins for a quick check once built, but will test some more when (if!) the kids go to bed tonight thumbs up
tokyomatik
NO HARSH NOISE?? so maybe my memories have a too fast access?? the code ends with -7......??
spotta
Here's the numbers for my HT and Memory



As it quite normal for me with most DIY modules (apart from the Klee & Orgone Accumulator - which have the best bring up procedures ever) not having owned a Voice Vandal or having anything similar to compare it with I am not at all sure what exactly it should be doing, I normally wing it for a bit, find a use for it or sell it on!

Here's a quick video of how mine operates. Mine is totally quiet with no input no matter on the position of the pots/switches.
Once an input is plugged ,with all the frequency switches open circuit no pots have any effect apart from Distortion which attenuates the signal to nothing CW.
Then when the frequency bands are brought in an effect can be heard which is affected by the frequency pot but both the Delay and Feedback pots seem to have no effect at all.
Delay is jumpered and the only component I did not place was the power LED - didnt see the point.
glennfin
Just ordered 4 "vack-packs" for my circuit bending projects. Thanks for the tip on that! cool

MacSynth wrote:
Barcode wrote:
DJBRUTAL wrote:
OK, so how do we go about adding CV to this?


Vactrols!

Easy solution: http://store.synthrotek.com/Vac_Pak_PCB
tokyomatik
spotta wrote:
Here's the numbers for my HT and Memory



As it quite normal for me with most DIY modules (apart from the Klee & Orgone Accumulator - which have the best bring up procedures ever) not having owned a Voice Vandal or having anything similar to compare it with I am not at all sure what exactly it should be doing, I normally wing it for a bit, find a use for it or sell it on!

Here's a quick video of how mine operates. Mine is totally quiet with no input no matter on the position of the pots/switches.
Once an input is plugged ,with all the frequency switches open circuit no pots have any effect apart from Distortion which attenuates the signal to nothing CW.
Then when the frequency bands are brought in an effect can be heard which is affected by the frequency pot but both the Delay and Feedback pots seem to have no effect at all.
Delay is jumpered and the only component I did not place was the power LED - didnt see the point.


I see......since I ordered 2 of those delay ICs, yesterday I tried the other one and the result is the same as you, no more noise but also not so much is happening when I move the rate & feedback pots.....tomorrow I will try to get a couple of ICs from Banzai and maybe also the memories, the 41256 that they have are rated 120ms
https://www.banzaimusic.com/IC-41256.html
....could that be ok for this project??
crustypaul
spotta wrote:
Here's the numbers for my HT and Memory




That RAM should work ok, but look at the Holtek logo on your HT8955A compared to the one on the genuine IC i posted a picture of.
Yours looks like it was drawn by a child with a crayon who'd had the logo explained to him, but had never actually seen it!
spotta
crustypaul wrote:

That RAM should work ok, but look at the Holtek logo on your HT8955A compared to the one on the genuine IC i posted a picture of.
Yours looks like it was drawn by a child with a crayon who'd had the logo explained to him, but had never actually seen it!

Yep! shame it always looks perfect on the picture they use to sell them.
Got my money back though.
delayed
Mine came with the incorrect logo also. The letters are almost vertical compared to the proper angled logo. Though they are listing an image with the correct date code and logo.
MatrixModulator
Hey!

I just bought a pcb yesterday and i was looking at the pcb image and ordering parts.

I was wondering if any of you are using it in a eurorack system?

I'm asking because i see "mic" and "line" levels inputs on the pcb, that being said, modular levels are higher than that so... How do you deal with that? Does it responds well without modifying anything?

I know i can use an attenuator before going into the Taxidermist but i would prefer to use my attenuators for other useful duties.

Thanks smile
scrubber
Any panels available for this still?
Barcode
scrubber wrote:
Any panels available for this still?


I have a couple "blemished" panels left. They have a few scratches and whatnot on them.

If we can get enough people interested I can do another run....
crustypaul
Barcode wrote:

If we can get enough people interested I can do another run....


How many is enough?
Barcode
crustypaul wrote:
Barcode wrote:

If we can get enough people interested I can do another run....


How many is enough?


I can do a batch if I have 5 committed people. I'm thinking about doing a different color on this one.
spotta
MatrixModulator wrote:
Hey!

I just bought a pcb yesterday and i was looking at the pcb image and ordering parts.

I was wondering if any of you are using it in a eurorack system?

I'm asking because i see "mic" and "line" levels inputs on the pcb, that being said, modular levels are higher than that so... How do you deal with that? Does it responds well without modifying anything?

I know i can use an attenuator before going into the Taxidermist but i would prefer to use my attenuators for other useful duties.

Thanks smile

Only had a quick test, waiting for a real IC to turn up but no level issues noticed.
teebeehex
Barcode wrote:
I can do a batch if I have 5 committed people. I'm thinking about doing a different color on this one.


What colour were you thinking?

I'd also need to know a price before fully committing.
Barcode
I was thinking blue. They are $12 each plus shipping.
teebeehex
Blue with that silver lettering, sounds good. Book me in for one, thanks.
crustypaul
Any chance of adding a switch for the delay jumper on the panel?

Given a choice I think i'd prefer the yellow, but either way put me down for one. wink
oberkorn
got mine to work this evening.
made a *stupid* mistake that had me swapping ICs, reflowing solder joints and whatnot for over an hour
until I noticed that I had wired the input jacks to the output pads and vice versa... d'oh! help seriously, i just don't get it

anyway I'd like to try the sample rate mod that was mentioned further up the thread by Eloc where R31 (5k6)
is replaced by a pot, does a 10k here sound completely off? or has anyone tried it and have any insight/experience??
Bamboombaps
Barcode wrote:
crustypaul wrote:
Barcode wrote:

If we can get enough people interested I can do another run....


How many is enough?


I can do a batch if I have 5 committed people. I'm thinking about doing a different color on this one.


if im not too late i want one of yours panels please barcode
Bamboombaps
sorry cancel my interest ive got one
tokyomatik
Eloc wrote:
tokyomatik wrote:

Ups! Yes I was meaning a 4066......
my question was kind of incomplete.......Can I send triggers or gates to the control pins of the 4066, without attenuation?


CD4xxx inputs should be able to take any signal up to the power rail voltage, but you want to avoid negative voltages. Best to put something like an op-amp set up as a comparator followed by a diode in front of the control pin to be safe.

so, I breadboarded on the fly a 4066, with just a resistor and a diode before the control pin and suddenly the term "chopper" of this effect start to make sense.
when u turn distortion fully CW the signal is coming out only if everytime a gate is coming.
The only thing I'm not so sure the circuit is working correctly, with 4ms SCM no problems, then I tried the TipTop Trigger Riot nothing... Also tried with a yusynth adsr and looks like is working with cv too....kind of.....
So I think is time to start to work on the comparator U mentioned before.
What I'm trying to do is to have push buttons and gate/triggers insted of the toggles but keeping the latching mode....I hope it's possible...??
here a sketch of what I did till now,not much to be honest but is a beginning...
tokyomatik
AH! and I almost forgot: Leds!! so that u can see the state of the switch...

anyway I would suggest to anyone who want to build one of this to take this idea in consideration, once u try with trigger to swith the band frequencies the toggles are just too boring...wink....
masterofstuff124
I'm in for a panel if there is a run going on!
Barcode
I have a couple other PCB designs I'm finishing up, then I will do another run in yellow. I should be placing the order in the next couple weeks.
cupwise
i'd like 4 panels!
Barcode
Sounds good guys. I'm putting in an order next week.

This run will be yellow.
oberkorn
here are the results of replacing R31 with a 10K pot to change the sample rate
https://vimeo.com/174263715
navej80
oberkorn wrote:
here are the results of replacing R31 with a 10K pot to change the sample rate
https://vimeo.com/174263715


Thanks for sharing. Definitely going to have a go at this mod.
MatrixModulator
Ok.. i bought one HT8955A from ebay but as i can see they are fake (i have not tested it).

Where can i get a real HT8955A theses days?

There's some at small-bear but 15$USD of shipping for one IC is a bit a pain in the ass.

http://smallbear-electronics.mybigcommerce.com/ic-ht8955a/

Thanks razz
mcop
Finally had a bit of time to work on this and here's the results so far.



I've added gate inputs on the frequency switches using another 4066 and comparators built with an LM339. This enables any signal passing the one volt threshold to turn the switch on or off - so envelopes, lfo's as well as gate signals. Haven't had a chance to record it but sending fast lfo's into these inputs does really nice things!

Here's the schematic for my modifications: gate-mods-for-taxidermist.pdf
davelybob
mcop wrote:

Here's the schematic for my modifications: gate-mods-for-taxidermist.pdf


Nice job! I'm rubbish at converting schematics to breadboard, any chance you could draw up a breadboard diagram to follow or maybe throw up a picture of the circuit?

Also, I just ordered a bunch of 4N25s that I plan on using to add CV to all 5 pots (including delay sample rate). The only optocouplers I have ever used were some old CLM6000s that I threw in a 4MS Stereo Panneur, so if anybody has any tips on using the 4N25 chips for CV inputs, I am ALL ears.

Thanks y'all.
crustypaul
mcop wrote:
Finally had a bit of time to work on this and here's the results so far.





Thats sounding excellent! Looks like theres another project to add to the ever growing list! cool


davelybob wrote:
Also, I just ordered a bunch of 4N25s that I plan on using to add CV to all 5 pots (including delay sample rate).


Have you got confused between optocouplers and vactrols?
Crashlander42
Really liking the taxidermist. Here's how my panel turned out.



I can upload an SVG if anyone's interested.
davelybob
crustypaul wrote:

Have you got confused between optocouplers and vactrols?


OH SNAP. Yep, that's exactly what I did. Thought I was being clever, should've been my first clue I was on the wrong track...
Barcode
Just a heads up.... I placed the order for panels today.
davelybob
davelybob wrote:
crustypaul wrote:

Have you got confused between optocouplers and vactrols?


OH SNAP. Yep, that's exactly what I did. Thought I was being clever, should've been my first clue I was on the wrong track...


OK, went back around to my local shop now that I know those chips coming from Mouser won't work. So now I'm sitting on a fistful of CLM8000s and VTL5C3/2s I'm leaning towards the VTLs since they have a faster decay time than the CLMs. I'm still looking over the datasheets, if anybody has ideas as per implementation (do I really need a opamp to drive these? got a good circuit?) I'd love some input. Otherwise if I don't turn up something I'm confident in, I'll just experiment starting with just a straight jack-vactrol-pot connection once I get my antilog pot from Mouser next week.

Paul, I'm looking to throw one of these onto the LTC1799 in my Rex50 as well if you have any thoughts on that.

My CVs will be coming from a Baby 8 or my Micromoog if that makes any difference. I've been soldering up little projects for years but just now starting to dip into CVs and gates and triggers and such, so apologies if I ask any dumb noob questions.

EDIT: Also, just realized I got these for a steal. CLM8000s were $2.95 each, VTL5C3/2s were $1.25 each. Might have to go back up there and stock up. Said his stock of the CLM6000s that I got from him last time was LONG gone, and permanently so.
thenormanconquest
anyone else have the problem where the chopper sound overtakes the whole audio path? as in, that's the only thing i hear when i engage the chopper section of the circuit. the delay sounds great, passes audio no problem. probably gonna switch out the LM358s and maybe the 4066, but wanted to see if anyone else had the same issue as me first.

thnx!
Barcode
The panels are in. I must have picked the wrong color when placing the order.... They came in a "burnt orange". I actually really like it, so I repaneled mine.

The price is $12 plus shipping for the orangeish panel (I have 9 left). I do still have a couple "blemished" yellow panels for $8 (one is my old panel).

Send me a PM if you are interested and I will get you a shipping quote.

tokyomatik
Hi guys! I decided to try to convert the schematics from mcop
into a pcb....I don't have so much experience in circuit design but I know how to work with Illustrator, also keep in mind this is my first attempt, so for sure is possible to make it better but at least I would like to know if somebody noticed any mistakes, is not tested till now.....since the board would be the same footprint of the taxidermist, i thought maybe there is also enough space to add some leds and why not, I was thinking also 2 "vacpak" circuits.... but first I need to know if till now i'm working in the right direction.....
when the design is ready I will more than happy to share finally something with the community...
Starspawn
Not bad, but you cant put the -12V and Ground together.
Also illustrator is hell for this.
Coming from a CAD program to illustrator (for ease of importing SVGs) I discovered lots of simple functions for lines and such was crap in illustrator.
tokyomatik
ah you are right!! ! I forgot to fix that..... I'm a bit messy sometimes...
I would like to implement also leds to show the frequency bands state,
I thought maybe right after R2, R7, R12 & R17
suggestions for a better spot??
mcop
tokyomatik wrote:
Hi guys! I decided to try to convert the schematics from mcop
into a pcb....


Cool
I've actually been working on a pcb layout myself. Haven't had a huge amount of time to play though as I've been rather busy lately so haven't had a chance to finish it, get some made and verify it.
I'm also intending to use the circuit to control other bits of kit I have which have footswitch inputs - hence the jack board and the position of the connections.

tokyomatik
that's a cool idea,there are many circuits that would get even more funny if u can automate the switching part....
on my side I'm more into expanding the possibilities of the taxidermist so I will try also to squeeze in 2 vacpak for chopper frequency & delay timerate control....ah yes also led action ; )!!
let's see if i can fit all on the same board and then I will upload the single sided design for pnp so i can finally give back something to this incredible community
mcop
Sorry it's taken so long. My original scribbling were a bit of a mess and hard to follow and it's taken a while to have time to redraw them.
Pink crosses in circles are cuts in the tracks.



davelybob wrote:
mcop wrote:

Here's the schematic for my modifications: gate-mods-for-taxidermist.pdf


Nice job! I'm rubbish at converting schematics to breadboard, any chance you could draw up a breadboard diagram to follow or maybe throw up a picture of the circuit?

Also, I just ordered a bunch of 4N25s that I plan on using to add CV to all 5 pots (including delay sample rate). The only optocouplers I have ever used were some old CLM6000s that I threw in a 4MS Stereo Panneur, so if anybody has any tips on using the 4N25 chips for CV inputs, I am ALL ears.

Thanks y'all.
mcop
Good stuff, the more we share the more we learn.
I'm still debating adding voltage control to my build. I'm leaning towards building another as a module and adding to that.

tokyomatik wrote:
that's a cool idea,there are many circuits that would get even more funny if u can automate the switching part....
on my side I'm more into expanding the possibilities of the taxidermist so I will try also to squeeze in 2 vacpak for chopper frequency & delay timerate control....ah yes also led action ; )!!
let's see if i can fit all on the same board and then I will upload the single sided design for pnp so i can finally give back something to this incredible community
Barcode
I have 3 of the orange panels left. Get them while you can!
perdex
Does anyone have panels in Europe?
yan6
Nevermind Mr. Green
yan6
I'm just getting to wiring this up with a barcode panel, is low switch 1?
crustypaul
This is answered up the thread somewhere, but if i recall correctly the highest one is on the left by the cap, and the lowest is on the right, by the four resistors..... if thats what you're asking.
yan6
Is there a schematic available I powered mine on and dont get any sound. I can very faintly hear my input if I select mic instead of line. I confirmed voltages at the input and from the regulators.

Starspawn
Cant see anything obviously wrong unless that lower right resistor isnt in full shadow but cooked.
yan6
haha, you had me worried so I checked, its in full shadow
yan6
I found a sweet package with a schematic and other goodies here. I was able to trace my signal to an un-soldered distortion pot d'oh! no matter how much experience you gain, its always something dumb lol It works and sounds good now thumbs up
crustypaul
yan6 wrote:
Is there a schematic available I]


For anyone interested, there s link to a more readable schematic on the last page of the build guide PDF.
sicpaul
Hi Wigglers,

i did read a lot about fake chips and bad sounding, so i decided to buy a second pair of RAM/echo chips from UK-electronic (HT: 0514K0213) to be on safer side.


But my problem is, i do not get any echo at all (with all combination of chips). Distortion secttion is working. I used 7809 and 7805 regulators and get adequat Voltages.

(If wondering about two resistors near C21: i had no 4k7 Ohms resistor, so i took two 10 Ohms in parallel).

Any hints where i should focus / what is to measure?



Bottom view
Front view
Starspawn
Two 10 ohm in parallell is 5 ohm, not 4.7 Kohm
4K7 means 4.7K
sicpaul
Starspawn wrote:
Two 10 ohm in parallell is 5 ohm, not 4.7 Kohm
4K7 means 4.7K


Well, you're right, but it was my typo, R33 was given as 4R7 not 4k7.
So 5 ohms should not cause my problem.
Starspawn
I did find that grounding the pots was actually necessary for the feedback to work properly, and to test if switch is correct you could short together the delay jumper?
sicpaul
Starspawn wrote:
I did find that grounding the pots was actually necessary for the feedback to work properly, and to test if switch is correct you could short together the delay jumper?


All pots are connected to ground and i measured my switch for closing the feedback bridge correct when pressed. But anyway, there should be at least a single delayed sound even if feedback bridge is not closed. I don't get any.
crustypaul
sicpaul wrote:
Hi Wigglers,
i did read a lot about fake chips and bad sounding, so i decided to buy a second pair of RAM/echo chips from UK-electronic (HT: 0514K0213) to be on safer side.


Realistically if both your HT8955A'a are from the same place and have the same code, then if one of them doesn't work then it'd be a pretty safe bet that the other one doesn't either.
Having said that, i think there was someone further up this thread who said they were using a 0514K0213 chip that worked fine.
Delabelle
Barcode wrote:
I decided to go with 10hp since I dislike having the PCB so close to the edge of the panel. Here's the start of my design.

I plan on doing the panel in yellow to match the PCB from cb.



I would like to make the panel.Can somebody share their panel drawing please?

Thx again,

G
Delabelle


Here is my first attempt for the phonic taxidermist. Inspired on the one I found here wink

Cheers
crustypaul
Whats happened to the P of Phonic there?

With limited panel space you might find it more useful to have a Delay return on/off switch, rather than a mic/line switch. I guess it depends on how you 're intending to use the thing, but will you ever be using mic level signals?
Delabelle
It s like that in the font smile delay return switch not bad ... but would like to hear my voice through the module sometimes wink

I m still looking for an existing harmonic engine from circuitbenders panel from somebody... anybody?

Jooooooo
Delabelle
Hello,

Panel for the Phonic Taxidermist available at ponoko.

http://www.ponoko.com/design-your-own/products/phonic-taxidermist-1379 3



Cheers
Delabelle
Ponoko frontpanel arrived, waiting for the chips
tekzon
Hey guys!
A few questions before I order the pcb,
Those who build it with success:
Would you share you card, mouser or whatever?
Where did you find that IC?
Do you have a good one spare?
Barcode, do you still have a panel to sell?
Etc..
Thanks a lot


EDIT
Just ordered a bundle from Paul.
Thanks
mmagin
I haven't yet built mine, but I bought the HT8955A as a used IC from a domestic seller with good ebay feedback, "dalbanicorporation" (probably a lot safer than the Chinese IC sellers), and I bought the RAM IC from jameco.com (which seems to stock a lot more surplus stuff. Definitely going to be socketing both just in case I have trouble.
OsakaScott
Greetings. I've sent a PM to Paul from Circuitbenders on Facebutt already about this, but being the impatient bastard that I am, and with the idea that more heads are better than one, I thought I'd post here as well.

I built two of these, and they both work, but they both exhibit the same sort of odd behavior, being that the delay, feedback and distortion work, but the frequency pot doesn't seem to really have any effect at all—all it does is introduce a rather high frequency whine, which is only barely evident between about 1 or 2 o'clock and max.

After finishing the builds, and playing around with both, I thought, "Well the delay is pretty normal, and the distortion is pretty standard too, but I was thinking there would be more of an actual 'effect' to the thing. Hmmmm." Which led me to re-watch the YouTube videos that put the idea that I Must Have This in my head. Upon watching I learned that evidently there is something amiss with my builds, as there is a very pronounced effect going on with those that is just absent from mine.

The only parts that I substituted from what was listed on the BOM are the four transistors and some capacitors. I can't find BC548 transistors here, so instead I used 2N3904 but placed in reverse from what is screened on the PCB thanks to a different pinout between the two. Regarding the poly film capacitors, seeing as the shop I frequent didn't have them (and unless I spend over $50, it's a $20 shipping slapola to get stuff sent here to Japan from Mouser) I used same value "Multilayer metalized polyester film" capacitors made by Nissei. Little blue jellybean looking things. Now I see the shop has received a huge shipment of WIMA capacitors so I'm wondering if it's worth swapping the current ones out for those.

I've checked that the pots are the right values and oriented correctly (they are). I've also checked that the ICs are the right numbers and put in their sockets the right way (they are). I used a CD4060BE, would a 74HC4060 make a difference?

I'm using a 12V power supply, with reg1 being a 78L12. Aside from no real effect via the Feedback knob, it works fine so I don't think this is an issue.

Any ideas?

Much appreciated, and thanks in advance smile
OsakaScott
For anyone following this... Here's an update.

Paul suggested checking the following:

Power. I've got a 12v switching supply that I measured at 12.26v 0.7a. I'm getting +5.06v at pin 16 of IC4.

R7 - R10, 100K? I checked both units, and these are all within tolerance (between 99.0 - 99.7K).

R16 - R19, 10K? This is where the fun began. Check this out:

Unit 1 Unit 2
R16 2.85K 9.88K
R17 2.85K 9.90K
R18 2.85K 9.90K
R19 2.85K 9.90K

So I decided to check all 10K resistors:

Unit 1 Unit 2
R1 6.94K same
R2 6.90K 6.92K
R4 9.97K same
R15 9.96K same

Not so different, but then there was this:

Unit 1 Unit 2
R25 5.57K 9.06K
R26 5.56K 9.02K

And lastly R36 which measured at 9.96K on both units.

Now, I've read that it's impossible to get an accurate reading when measuring resistors that are soldered to a PCB. Is this really the case though? I measured by touching the probes to the part where the leg and the main body of the resistor meet, without touching the PCB itself, though on the populated side of it. I'm no expert at troubleshooting, I mean basic stuff I can deal with, but why the resistor values should vary so much baffles me. Visually, they are all labeled 10K (Brown Black Black Red Brown).

Any ideas?
Jaytee
If they're installed in the PCB, it messes with the readings because the two points you're measuring may be connected in some other convoluted way.

As for why the two units differ so greatly in their measurements, not sure. Although if they have the same fault, different readings in each unit would seem to indicate it's not part of the problem.
Jaytee
OsakaScott wrote:
I'm using a 12V power supply, with reg1 being a 78L12.


This may not be the issue, but a 78L12 won't properly regulate if you feed it only 12V. You probably want a 78L09 there instead.

This may not be the issue, since it should run on less than 12 volts, but it's at least worth looking into.
fuzzbass
Jaytee wrote:
If they're installed in the PCB, it messes with the readings because the two points you're measuring may be connected in some other convoluted way.

As for why the two units differ so greatly in their measurements, not sure. Although if they have the same fault, different readings in each unit would seem to indicate it's not part of the problem.


I have never gotten a true reading measuring resistors or caps in circuit. I always end up pulling one leg out.
OsakaScott
After a series of back n forth messaging with Paul from Circuitbenders, we still haven't figured the issue out. Dusted off the scope and probed the relevant pins on the 4066, only to find that the square waves are being output OK and they change as expected upon tweaking the frequency knob. At this point, it's looking like I might pull up one leg of the sketchy-measurement resistors and test again. It might also be that the 2N3904s are being finicky, though we don't know why such should be the case. Lastly, it might just be something as simple as not feeding signals which respond well to the chopping effect.

Thanks for the replies though.

smile
monstrinho
It could be something as simple as a bad pot. I've run into that before, and it turned out to be the last thing I checked for.
tekzon
Well, pcb and ic received! Thanks Paul

Does anyone of you have a panel to sell?

Thanks
Starspawn
Join me in nagging Barcode for a new run, I need 3 wink
tekzon
Starspawn wrote:
Join me in nagging Barcode for a new run, I need 3 wink


Ha ha, come on barcode!
we're not worthy
cranleigh
+1 barcode! In the market for a panel too
Starspawn
Well, since then Ive found alternative panels.
Barcode
Oh crap. I totally missed all the requests. I can do another run in the next week or so. I'm going to change the graphics up a bit...
cranleigh
we're not worthy we're not worthy cheers!
der Warst
Whee,
so I finished my first phonic taxidermist and it's working and all!

One of the reasons I got it was the hope that being a delay with external ram, it would be possible to do some nice address-line bends with it. Sadly, all that happens when you short the address lines to ground, 5v or each other, is producing very nasty digital noise, so I guess I'm not really gonna pursue this much further.

One super useful thing that I found out to work well though (and that usually works with most ram-based delays), is shorting the 3rd (WE, or write enable) pin of the ram to 5V. This creates a permanent loop out of what has gone through the delay before. Unlike with a full open feedback, this loop will run forever without degrading, much like a looper pedal. If you put a switch in there, you can easily turn it on and off to add more sounds to the loop.

I'm kind of surprised no one else has come up with this idea so far, as it is a pretty common bend with Ram based gear.

But yeah, try it out. Have fun.
Starspawn
Barcode wrote:
Oh crap. I totally missed all the requests. I can do another run in the next week or so. I'm going to change the graphics up a bit...


Other source didnt work out, so ill add an request for four again wink
cranleigh
Still in the market for one too.
crustypaul
Probably have some panels available soon if anyones interested.
Its based on Barcodes one, but with a delay return switch instead of a mic/line switch.

Starspawn
Yes, whichever one of you that can get me four gets cash wink
cranleigh
I'll take a panel, thanks!
crustypaul
Ok, theres a few panels available on the circuitbenders site for £7, or theres a few B-stock ones with minor marks for £5.

https://www.circuitbenders.co.uk/forsale/phonictaxi/ptaxi.html#euro
timequake
hi all!
just received the PCB... i'm wondering if BC548A, BC548B or BC548C would be a suitable substiitute for the BC548? or should i go with the 2N3904?
thank you! smile
zdarma
any word on these pcbs becoming available again?
crustypaul
zdarma wrote:
any word on these pcbs becoming available again?


Probably the first week of November if everything goes to plan.
member123
Just built a PT but only have feedback and distortion working. Anyone got ideas of where to look? Much appreciated!
member123
All good. Shaky HT8955 and a delay pot with wrong value!
grm
Hi there,
thanks for drawing the stripboard layout for the gateed switches. i have build it and tired it out last night, but unfortunately without success.

it seemed like all switches were always on, regardless of state and without any gate input even. i've measures and no matter what position the switches were in, i had about 11v on both sides of the 47k resistor and the IN pin on the stripboard. meanwhile the switch pins IN/OUT were always closed. with a little resistance when measured with power on.

and now i would like to ask a few questions:

- what's with the diodes from the schematic, they are not on the stripboard-drawing and not in my build. are they not needed?

- SW#in and SW#out go to the switch connections on the PCB. what goes where doesn't matter, right? it would only be interesting that the connection is open or closed.

- i am using a CD4066BE IC is that the right one?

- Vre is 1v, is that correct?

- are the IN# pins on the stripboard the ins (tips) of the gate signal?

i'm sure ,i forgot something. but this so far. any help very appreciated. thank you.





mcop wrote:
Sorry it's taken so long. My original scribbling were a bit of a mess and hard to follow and it's taken a while to have time to redraw them.
Pink crosses in circles are cuts in the tracks.



davelybob wrote:
mcop wrote:

Here's the schematic for my modifications: gate-mods-for-taxidermist.pdf


Nice job! I'm rubbish at converting schematics to breadboard, any chance you could draw up a breadboard diagram to follow or maybe throw up a picture of the circuit?

Also, I just ordered a bunch of 4N25s that I plan on using to add CV to all 5 pots (including delay sample rate). The only optocouplers I have ever used were some old CLM6000s that I threw in a 4MS Stereo Panneur, so if anybody has any tips on using the 4N25 chips for CV inputs, I am ALL ears.

Thanks y'all.
FetidEye
did anyone attempt to make this delay voltage control-able?
(like, delay time, feedback etc.)

edit: oh, I see something is possible with vactrols and gate inputs.
a mod schematic?
mcop
Sorry, hadn't noticed the mistake with the layout. There's also 4x100K resistors missing on the layout as well as the diodes. The diodes protect the inputs to the comparator from signals below 0V. I made the diagram after building my own unit.
On my build the 10K, 100K and Diode are on a seperate bit of stripboard thet the jacks are mounted on. You could solder the two resistors and a diode onto each jack and then wire from them directly to pins 5, 7, 9 and 11 respectively of the LM339.

grm wrote:
Hi there,
thanks for drawing the stripboard layout for the gateed switches. i have build it and tired it out last night, but unfortunately without success.

it seemed like all switches were always on, regardless of state and without any gate input even. i've measures and no matter what position the switches were in, i had about 11v on both sides of the 47k resistor and the IN pin on the stripboard. meanwhile the switch pins IN/OUT were always closed. with a little resistance when measured with power on.

and now i would like to ask a few questions:

- what's with the diodes from the schematic, they are not on the stripboard-drawing and not in my build. are they not needed?

- SW#in and SW#out go to the switch connections on the PCB. what goes where doesn't matter, right? it would only be interesting that the connection is open or closed.

- i am using a CD4066BE IC is that the right one?

- Vre is 1v, is that correct?

- are the IN# pins on the stripboard the ins (tips) of the gate signal?

i'm sure ,i forgot something. but this so far. any help very appreciated. thank you.





mcop wrote:
Sorry it's taken so long. My original scribbling were a bit of a mess and hard to follow and it's taken a while to have time to redraw them.
Pink crosses in circles are cuts in the tracks.



davelybob wrote:
mcop wrote:

Here's the schematic for my modifications: gate-mods-for-taxidermist.pdf


Nice job! I'm rubbish at converting schematics to breadboard, any chance you could draw up a breadboard diagram to follow or maybe throw up a picture of the circuit?

Also, I just ordered a bunch of 4N25s that I plan on using to add CV to all 5 pots (including delay sample rate). The only optocouplers I have ever used were some old CLM6000s that I threw in a 4MS Stereo Panneur, so if anybody has any tips on using the 4N25 chips for CV inputs, I am ALL ears.

Thanks y'all.
vekter303
Hellooo,

Bitten by a DIY bug and relatively clueless, how does this BOM look?

It has a 2x 1/4 jacks and a panel mount DC jack.

Just not that sure of my stuff as far as components, so any feedback welcomed eek!
crustypaul
You don't need 3 voltage regulators. Either the 7809 or the 7812 with do, depending on your input voltage.

The B100K needs to be a dual pot. The one you have there is single.

I'd go for a C500K at VR3 if you can find one, but B500K will work.

If you post a link to a saved mouser project/shopping cart, it'd be a lot easier for people to check that you have the right things. Either that or links to the mouser part on your XLS file.
drox
keen to build one of these soon, I am a bit of a noob so if anyone does share a mouser cart that would be helpful. Otherwise I am looking at vekter303's excel file as a referance.
grm
hey, thanks.
will keep you informed about my progress or failures.

---

mcop wrote:
Sorry, hadn't noticed the mistake with the layout. There's also 4x100K resistors missing on the layout as well as the diodes. The diodes protect the inputs to the comparator from signals below 0V. I made the diagram after building my own unit.
On my build the 10K, 100K and Diode are on a seperate bit of stripboard thet the jacks are mounted on. You could solder the two resistors and a diode onto each jack and then wire from them directly to pins 5, 7, 9 and 11 respectively of the LM339.

grm wrote:
Hi there,
thanks for drawing the stripboard layout for the gateed switches. i have build it and tired it out last night, but unfortunately without success.

it seemed like all switches were always on, regardless of state and without any gate input even. i've measures and no matter what position the switches were in, i had about 11v on both sides of the 47k resistor and the IN pin on the stripboard. meanwhile the switch pins IN/OUT were always closed. with a little resistance when measured with power on.

and now i would like to ask a few questions:

- what's with the diodes from the schematic, they are not on the stripboard-drawing and not in my build. are they not needed?

- SW#in and SW#out go to the switch connections on the PCB. what goes where doesn't matter, right? it would only be interesting that the connection is open or closed.

- i am using a CD4066BE IC is that the right one?

- Vre is 1v, is that correct?

- are the IN# pins on the stripboard the ins (tips) of the gate signal?

i'm sure ,i forgot something. but this so far. any help very appreciated. thank you.





mcop wrote:
Sorry it's taken so long. My original scribbling were a bit of a mess and hard to follow and it's taken a while to have time to redraw them.
Pink crosses in circles are cuts in the tracks.



davelybob wrote:
mcop wrote:

Here's the schematic for my modifications: gate-mods-for-taxidermist.pdf


Nice job! I'm rubbish at converting schematics to breadboard, any chance you could draw up a breadboard diagram to follow or maybe throw up a picture of the circuit?

Also, I just ordered a bunch of 4N25s that I plan on using to add CV to all 5 pots (including delay sample rate). The only optocouplers I have ever used were some old CLM6000s that I threw in a 4MS Stereo Panneur, so if anybody has any tips on using the 4N25 chips for CV inputs, I am ALL ears.

Thanks y'all.
MUFF WIGGLER Forum Index -> Music Tech DIY  
Page 1 of 8
Powered by phpBB © phpBB Group