[BUILD] God's Box 'Humpback' - 8hp Eurorack Multimode VCF

From circuitbending to homebrew stompboxes & synths, keep the DIY spirit alive!

Moderators: Kent, Joe., luketeaford, lisa

Post Reply
FrJK
Learning to Wiggle
Posts: 9
Joined: Wed Jan 20, 2016 4:46 pm

Post by FrJK » Fri Aug 11, 2017 3:30 am

FrJK wrote:
DenisOvan wrote:Hey Frank, Post up some hi res pictures of your build, both sides of the boards. It's the best way to help Wigglers help you get to the bottom of your probs

Hi Denis, thanks for helping. Here are the pictures:
... based on my very low knowledge, I now think it is the 100R trimmer that is missing..

The build manual does mention it, but it was not in the kit, in this thread here I read that it was supposed to be removed, plus I do not find the trimmer in the schematic .... However, I will try with a trimmer ...

User avatar
ethnotronics
Wiggling with Experience
Posts: 432
Joined: Mon Mar 02, 2015 9:11 am
Location: Belgium

Post by ethnotronics » Fri Aug 11, 2017 2:56 pm

diode_destroyer wrote:Are more kits coming into Thonk in the future? Only found these now and I want one!
Me too!

FrJK
Learning to Wiggle
Posts: 9
Joined: Wed Jan 20, 2016 4:46 pm

Post by FrJK » Fri Aug 11, 2017 3:10 pm

FrJK wrote:
FrJK wrote:
DenisOvan wrote:Hey Frank, Post up some hi res pictures of your build, both sides of the boards. It's the best way to help Wigglers help you get to the bottom of your probs

Hi Denis, thanks for helping. Here are the pictures:
... based on my very low knowledge, I now think it is the 100R trimmer that is missing..

The build manual does mention it, but it was not in the kit, in this thread here I read that it was supposed to be removed, plus I do not find the trimmer in the schematic .... However, I will try with a trimmer ...
Fixed!
Luckily had 2 100R trimmers on hand at work, dropped them in and now they do.

User avatar
Staticcharge
Common Wiggler
Posts: 231
Joined: Tue May 05, 2015 2:02 pm
Location: Somewhere between yesterday and tomorrow.

Post by Staticcharge » Mon Sep 04, 2017 11:27 am

I'm looking to build another one of these with the PCB panel but there doesn't seem to be a BOP and there is no info on the C1 & C2 blue 220pF caps. Anyone have any idea what type they are or if a standard disc type will be ok. I've had a look on the schematic and both just go to ground but other than the value there's no more info on there either. I'm assuming it's a polyester film type?

User avatar
templar
Common Wiggler
Posts: 117
Joined: Sat Jul 11, 2015 8:30 am

Post by templar » Mon Sep 04, 2017 2:16 pm

220pf caps should be either Silver Mica or polystyrene

strewya
Learning to Wiggle
Posts: 10
Joined: Sat Apr 15, 2017 9:13 am
Location: London

Post by strewya » Mon Sep 04, 2017 2:43 pm

Hi peeps,

I'd love to build this filter but at the moment there are no full kits at thonk.

I don't mind sourcing part but can't see BOM anywhere ? Could anyone point me in the right direction please.

Many thanks 8-)

User avatar
Staticcharge
Common Wiggler
Posts: 231
Joined: Tue May 05, 2015 2:02 pm
Location: Somewhere between yesterday and tomorrow.

Post by Staticcharge » Tue Sep 05, 2017 11:10 am

strewya wrote:Hi peeps,

I'd love to build this filter but at the moment there are no full kits at thonk.

I don't mind sourcing part but can't see BOM anywhere ? Could anyone point me in the right direction please.

Many thanks 8-)
Steve has put the BOM with the other documents.
I've got everything else but the 220pF silver mica caps are hard to find and there still isn't a voltage rating.
Anyone have any ideas where I can get them in the UK?

User avatar
Staticcharge
Common Wiggler
Posts: 231
Joined: Tue May 05, 2015 2:02 pm
Location: Somewhere between yesterday and tomorrow.

Post by Staticcharge » Tue Sep 05, 2017 11:27 am

templar wrote:220pf caps should be either Silver Mica or polystyrene
Will these be ok?
Axial Polystyrene HSQ220PF2160V 220PF 160V 2%.
Also can I use polybox caps for 0.15uf and 0.33uf?

User avatar
templar
Common Wiggler
Posts: 117
Joined: Sat Jul 11, 2015 8:30 am

Post by templar » Tue Sep 05, 2017 1:17 pm

Those styrene caps should be fine

Looks like those other values are specified as polybox anyway

User avatar
Staticcharge
Common Wiggler
Posts: 231
Joined: Tue May 05, 2015 2:02 pm
Location: Somewhere between yesterday and tomorrow.

Post by Staticcharge » Tue Sep 05, 2017 2:16 pm

templar wrote:Those styrene caps should be fine

Looks like those other values are specified as polybox anyway
Thanks for your help.

User avatar
Staticcharge
Common Wiggler
Posts: 231
Joined: Tue May 05, 2015 2:02 pm
Location: Somewhere between yesterday and tomorrow.

Post by Staticcharge » Sat Sep 09, 2017 9:38 am

Those caps worked fine Templar. Bought some naff CA3080 ICs though so waiting for replacements. Tested against the Ti ICs I've got in my other Humpback I've got no cutoff after say 1/4 turn.
My plan is to build a twin Humpback based on the BF-22 but looking like this:
Image

Saint and sinner switches ar for the hotrod res jumper on the back of each module. Link is output of left to input of right and the knob below is for link type ie LP.BP.HP.N but I've got to get the indicator to line up with the letters before deciding where they need to go. Work in progress

Ms304671
Learning to Wiggle
Posts: 12
Joined: Thu Apr 06, 2017 9:29 am
Location: Liverpool/ Leeds

CA3080e

Post by Ms304671 » Mon Sep 11, 2017 2:54 pm

Hi all,

Struggling to find CA3080e ICs here in the UK and im reluctant to purchase on ebay for fear of fakes. Can anyone reccomend a good place to purchase or perhaps have any they would be willing to sell?

Thanks in advance!

:help:

User avatar
templar
Common Wiggler
Posts: 117
Joined: Sat Jul 11, 2015 8:30 am

Post by templar » Mon Sep 11, 2017 4:01 pm

edit: see below
Last edited by templar on Mon Sep 11, 2017 5:17 pm, edited 1 time in total.

User avatar
MAXTHEDOG
Wiggling with Experience
Posts: 402
Joined: Sat Dec 17, 2016 8:15 am
Location: All over di place, maan.

Post by MAXTHEDOG » Mon Sep 11, 2017 4:33 pm

Hi,
Try Cricklewood Electronics -£4.50+VAT.

Regards,
MtD.

Ms304671
Learning to Wiggle
Posts: 12
Joined: Thu Apr 06, 2017 9:29 am
Location: Liverpool/ Leeds

Post by Ms304671 » Tue Sep 12, 2017 12:31 am

MAXTHEDOG wrote:Hi,
Try Cricklewood Electronics -£4.50+VAT.

Regards,
MtD.
Thanks mate :tu:

User avatar
MAXTHEDOG
Wiggling with Experience
Posts: 402
Joined: Sat Dec 17, 2016 8:15 am
Location: All over di place, maan.

Post by MAXTHEDOG » Tue Sep 12, 2017 3:14 am

No probs.
I did the Humpback from the full kit. Nice easy build and sounds great. Goes manic with the jumper switched over.....
MTD.

User avatar
Staticcharge
Common Wiggler
Posts: 231
Joined: Tue May 05, 2015 2:02 pm
Location: Somewhere between yesterday and tomorrow.

Post by Staticcharge » Wed Sep 13, 2017 12:06 pm

I've ordered 10 Harris ca3080 Ics. Although from ebay, if they are fake your covered by using PayPal. Though the LM13700 is a dual 3080 but you'll have to build an interface for the larger IC. Worth looking into, word on the street is the 3080 die was lost in a fire at Ti, not sure how true that is.

hirada
Common Wiggler
Posts: 144
Joined: Mon Dec 01, 2014 9:17 am

Post by hirada » Mon Sep 18, 2017 7:39 am

Hello,

a question about the BOM. Except the panasonic ECQ-V1J334JM, which seems to be available only in the US and only if you buy for more than $200, I have most stuff together. Kits haven't been available, so I went just for PCB and panel.

Any recommendation for an alternative to the panasonic? Are those somewhat relevant as the mica silvers are supposed to be?

Another uncertainty is the shunt. What are you taking for this one? Usually I know a shunt as a precision very low resistance device, but of course I have no data about this one.

Finally the Hex Spacer, how long are those supposed to be?

Thanks for any help. Still new to DIY.

User avatar
MAXTHEDOG
Wiggling with Experience
Posts: 402
Joined: Sat Dec 17, 2016 8:15 am
Location: All over di place, maan.

Post by MAXTHEDOG » Mon Sep 18, 2017 12:39 pm

Hi Hirada,

Don't know where you are but try these-

Capacitor:
http://uk.farnell.com/w/c/passive-compo ... posneg-5pc
Farnells have the Panasonic one but say it's no longer manufactured.

Shunt/Jumper:
http://uk.farnell.com/w/c/connectors/co ... st=Jumpers

I did mine from the full kit so never saw a BOM. IIRC the hex spacers are the same height as the PCB connectors so I would guess about 12.7mm.
Get the PCB's and fit the board connectors temporarily together you'll soon see how long the hex spacers need to be.

Hope this helps,
MtD.

User avatar
infovore
Wiggling with Experience
Posts: 323
Joined: Wed Nov 11, 2015 9:36 am
Location: London

Post by infovore » Wed Oct 04, 2017 9:59 am

Just a quick note for those of you building your own from PCB/panel - it's been designed around 5mmx7mm aluminium caps; if your caps that you've got kicking around your parts box are taller than 7mm, you will have problems a) sandwiching the two boards and b) getting the panel on. You need stumpy caps.

This advice brought to you by: me, who discovered this the hard way. The BOM has the details.

hirada
Common Wiggler
Posts: 144
Joined: Mon Dec 01, 2014 9:17 am

Post by hirada » Thu Oct 19, 2017 5:01 am

Thanks for your help, MTD and sorry for the late reply, been completely away from anything modular. Also thanks for the heads up with the alu caps.


So far I've found the Panasoncic ECQ-E2334JF as replacement, they are slighty thicker, about 1mm, but should fit according to the doc, and for the shunt I've should have read the build doc more thoroughly, it's just an ordinary jumper.

The panasonics are General Film Capacitors as opposed to Stacked Film Capacitors from the original choice, whatever that may mean. Not sure wehter they actually are sound relevant.

Kemet hast stacked film capacitors, but only in 5mm spacing, not 7.5.


However, is it possible the something completely unimportant as the ssm2220 IC is missing in the BOM? Will be the next adventure organizing this. Anyone by chance ordered from goodtronic in china maybe?

butter
Common Wiggler
Posts: 56
Joined: Fri Mar 04, 2016 9:38 am

Post by butter » Sat Nov 04, 2017 5:58 am

Another pcb/panel build here, have managed to find pretty much everything I need, but would appreciate if someone could help out with the last two bits... Feel a bit silly asking, but this is my first move beyond full kits, still feeling my my around what is likely obvious!

- what is the size/height of the hex spacer? My mated headers seem to be about 11mm, not sure if that means standard spacers are 10,11 or 12mm? (or in light of the "less than 7mm height caps" post, any merit in going a bit bigger here?) I'll likely be getting a few extra, but suspect I've already picked up enough "stock" of parts that are just out of normal range haha.

- the 10uF caps I have seem unlikely to fit - could anyone point me in the direction of the "stumpy" caps? Keep feeling I'm ending up finding the wrong "family" when I search based on size...

Thanks!

echox
Common Wiggler
Posts: 109
Joined: Fri Oct 07, 2016 8:02 pm
Location: Germany

Post by echox » Sat Nov 04, 2017 7:01 am

infovore wrote:Just a quick note for those of you building your own from PCB/panel - it's been designed around 5mmx7mm aluminium caps; if your caps that you've got kicking around your parts box are taller than 7mm, you will have problems a) sandwiching the two boards and b) getting the panel on. You need stumpy caps.

This advice brought to you by: me, who discovered this the hard way. The BOM has the details.
Yep...

I managed to work around this by bending them 90 degrees. So they lay flat on the board which works for the most places ;-)

echox
Common Wiggler
Posts: 109
Joined: Fri Oct 07, 2016 8:02 pm
Location: Germany

Post by echox » Sat Nov 04, 2017 8:53 am

Since the kit is unavailable for a long time I bought the Panel + PCB option.

The filter is fully populated but I can't get it to work... :-/

Error description:
BP: I have to match exactly the signal with the cutoff, otherwise nothing can be heard.
LP: nothing

Input amplification seems to work and resonance seems to work if I match exactly the frequency.

Other things: There is exactly one sweet spot where the filter 'self-oscillates' but sounds like a square wave.

Things I checked:
Measured the resistors twice.
Double checked the solder joints and reheated most of them (just to be sure).
Sandwich board connection (measured the individual connection pins from both sides)
Orientation of the components (caps, ICs)
Any shorts...

Here is a picture of the components:

Btw.: The bended caps look a little bit strange but I tripple checked if there are any shorts or something like this, so they should be fine.

Any help is appreciated.

Image

User avatar
diode_destroyer
Common Wiggler
Posts: 201
Joined: Thu Nov 03, 2016 7:08 pm
Location: Kansas

Post by diode_destroyer » Tue Nov 21, 2017 12:57 pm

I just wanted to report that I did the pcb+panel from Thonk, and first built it up with wima caps for the 220pf ones, then just recently changed out the 220pf caps for Silver Micas, and honestly can't tell a difference in sound...sounds the same to me.

Post Reply

Return to “Music Tech DIY”