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WIGGLING 'LITE' IN GUEST MODE

Frac Wiard NR Clock In Mod? (Details inside)
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Author Frac Wiard NR Clock In Mod? (Details inside)
DGTom
we're not worthy Tim Stinchcombe we're not worthy

Thanks for doing this! I know alot of us will be getting way more use out of our Frac Noise Rings now.

If possible are you able to tell if there is an extra ceramic cap as part of the noise generator on SandyBs? In the first pic I posted compared to the one Sandy posted on page 2 there appears to be a through hole part kludged in. I can send a higher res pic if it helps any.
Tim Stinchcombe
DGTom wrote:
If possible are you able to tell if there is an extra ceramic cap as part of the noise generator on SandyBs? In the first pic I posted compared to the one Sandy posted on page 2 there appears to be a through hole part kludged in.
Yes, it is a 100nF replacing the SMT part on the board (so no real connection to the mod at all). The noise has two gain stages, that is the first, a non-inverting set-up of up to x500 gain (via the trimpot in the feedback loop) - the cap is between the reverse-biased e-b junction of an NPN transistor and the non-inverting input of the OA (plus a 1meg to ground). I can't get a reading in-circuit for the SMT part, but can for the 100n, so I suspect the standard fit is much smaller.

Unfortunately I haven't been able to look at this project for the last three evenings, as all my time has been spent trying to troubleshoot my bread-making machine (which is irritatingly making really flat loaves) - however I think I'm on the trail of the problem of that now, so later this evening I can run some simulations of the noise circuit and see what changing that cap does (my suspicions are that it may impact the 'colour' of the noise..?).

Tim
DGTom
Cool, thanks, fix the bread maker first tho! Flat loaves is almost worse than no bread at all.

I've noticed the noise out of mine is kind of "scratchy" (for lack of a better term) so I wondered if the added cap is there to address that in the 8 jack version.
jenamu6
sorry.....but machines don't make bread....people do.
Tim Stinchcombe
Have just got back round to looking at these modules, and the first thing I did having created a harness so that I could power them up, was to look at the spectra of the noise outs, to see if any difference showed up between the standard SMT cap fit (whatever value that might be), and Sandy's modified module which has a 100nF leaded-component there instead - the results are quite marked:



The one with the 100n is markedly louder, but that could be down to the trimpot setting (I didn't have much time to spend on it, and didn't look at the amplitude of the signal...). However just as marked is that the 100n cap seems to be broadening the bandwidth, making the spectrum much flatter out to a higher frequency. I can't replicate this in SPICE, but that doesn't entirely surprise me, as I suspect I need to carefully 'frig' the DC levels in the simulation to get decent results out of it (so I'll continue to think about it some more). And potentially Grant might be able to confirm this directly, if he is listening in!

Tim
sandyb
that's quite a difference Tim!
fracmonkey
jenamu6 wrote:
sorry.....but machines don't make bread....people do.


Is your yeast fresh? And is the yeast growing temp within spec?

OH, sorry I thought this was the breadmaking forum........ Mr. Green
Tim Stinchcombe
fracmonkey wrote:
Is your yeast fresh? And is the yeast growing temp within spec?
New yeast was first thing I tried, as I had already bought a new packet as old one running low - no change; then thought it wasn't getting up to heat properly, so increased it by lowering a resistor - this made it worse, so I suspect I was killing the yeast with too much heat; now think perhaps it is the flour - I use a supermarket brand, and it took ages to get it right in first place (wholemeal bread, experience suggests tricky in a breadmaker), so maybe they have changed suppliers; next step is a white loaf, which from memory was easier to get a decent loaf from. All started with a new breadpan (the old ones was absolutely knackered), and it appears it wasn't totally responsible for the crapness of the bread...
Tim Stinchcombe
Tim Stinchcombe wrote:
The one with the 100n is markedly louder, but that could be down to the trimpot setting (I didn't have much time to spend on it, and didn't look at the amplitude of the signal...).
Well having now looked at the amplitudes, the reason for the difference in perceived loudness is due to the massively bigger signal on the modified module (the one with the changed cap):

- note the five times difference in the vertical scale!

I'm not sure what the effect on the obviously often-clipped larger signal will be on the spectrum, but in any case, having replicated the circuit on a small piece of breadboard, I doubt that is the issue - what is puzzling is the earlier drop-off on the module with the SMT cap. I also doubt that the addition of the leaded cap is necessarily to use a bigger one than the SMT cap - on my breadboard version, it needed to be about 100nF to stop the first op amp from oscillating (it clearly doesn't like the big impedances of the 1meg resistor and a smaller value cap!), and in any case the cap forms a low cut-off highpass effect with the 1meg, and increasing it just pushes this pole lower and lower, where its impact simply isn't seen (the Doepfer A-118 is quite a similar circuit, and the equivalent cap there is 2u2!).

I had to try about 8 or 9 transistors before I found one that had enough umph in it to get the output to saturate, and then adjusting the gain so that the output is either really weedy or is clipping produces a similar fairly flat spectrum to around 5kHz, then it rolls off, the only difference being how high or low the passband is, i.e. I have been unable to replicate nor account for the reason for the earlier drop-off of the module with the SMT cap. The chips are however a different make - the modded one is a TI TL074, the unmodded is an ST TL074 - but I doubt that could account for such a marked difference either. (There is also a resistor difference on the second gain stage of the modded module, giving that stage a gain of approx 45 as opposed to the other's of just 20, but all this will do is make it easier for the output signal to be clipped - the trimpots on both are around halfway.)

In short my conclusion is that deliberately changing that cap will have little to no impact on the noise output!

But all this is a diversion from the 'clock in' mod - I was going to do that this weekend, but my time has been severely 'fractured' due to unforeseen family matters (aren't they always), but hopefully I can get to do it during the week, and will publish a few pictures of what to do!

Tim
sandyb
Tim Stinchcombe wrote:
...
In short my conclusion is that deliberately changing that cap will have little to no impact on the noise output!

But all this is a diversion from the 'clock in' mod - I was going to do that this weekend, but my time has been severely 'fractured' due to unforeseen family matters (aren't they always), but hopefully I can get to do it during the week, and will publish a few pictures of what to do!

Tim


cry i thought it gave the modded one super powers!

thanks for your time and effort on this so far Tim smile
Tim Stinchcombe
Well I agonized over several of the details as to how to do the mod for a couple of reasons: the original method requires the removal of two surface mount (0805-sized) resistors, and for those that have never done this before (I'm guessing this is likely a fairly high percentage of those that will want to do this...!?), there is a significant risk in damaging the board/pads/traces in doing so; secondly, whilst there is an easier way to achieve the same effect, this was going to make Sandy's modules behave ever-so-slightly differently (which if they were mine, would have bugged the hell out of me!). Thankfully the tactic of not rushing into things, and mulling everything over for a few evenings revealed there was a staring-me-in-the-face obvious solution to the 'compatability' problem between the two methods, so here is my slightly (I think) easier way of doing the mod. It requires two fewer resistors and not removing anything, though there is still (unavoidably) some tricky soldering required to hook directly-up to SMT components.

Bits needed are:
- an ultra-miniature two-pole changeover switch. I used the code FH99H one of these - click the 'specification' tab for the size
- a 10k and 24k resistor (though a 27k would do equally as well rather than 24)
- thin hook-up wire (I used Kynar, as used already for the factory-fitted mod)

Here is the circuit detail of the mod itself - the switch and everything to the left of it is new, the rest is existing:



First thing to do is remove the wire running between the 'aux out' socket and the 'ext rate' socket (damn - forgot to get a picture of this!). Also cut the track running between the 555 and the TL074 chips:


Then drill the hole for the switch - I drilled slightly down from center, so as to match Sandy's other modified module, and also so that the switch won't obscure the writing:


An unfortunate downside of this is that it leaves less space for the switch between the sockets, which have to be angled out to make the space. I cut and removed the ground wire running through the tabs on the sockets, the bottom pair can then be rotated to make enough space for the switch, then re-thread some new wire and re-soldered everything (note the last snap in this sequence is taken from the top!):


Solder a 24k resistor between the ground wire and the left-lower tab on the switch:


The 10k resistor goes between the right-lower switch tab and the 'ext rate' socket - I bent the unused 'switching contact' tab out of the way, and with careful bending of the resistor legs I reckon the whole lot is sufficiently placed (and rigid) so as not to cause any possible shorting hazards, but use insulating sleeving as you think fit:


Then cut and strip three suitable lengths of wire, and tag one each in turn, to: the two 100k resistors making the potential divider:


...the 1k resistor just above the 555 chip:


...and pin 9 of the TL074 chip (if you don't have an empty socket in the 'EXP' 16-pin DIL footprint in the middle of the board, this one can go to pin 10 there, if you like - beep it out with a continuity tester and you'll see it is the same place!):


Then attach the other ends of the wires to the switch, as shown:


That's it! Here is snap of the whole, though I have yet to add a gob of goop to tag the wires in place:


When the switch is down, it runs off the internal clock; when up, the clock supplied through the 'ext rate' socket drives it.

With the 24k resistor, the level at which the external signal clocks the module is approx 2.4V, which is close to that of the original modification; if you were to use a 27k instead, it creeps up a little to about 2.6V (i.e. not a big deal).

Hopefully I haven't forgotten anything, though perhaps it goes without saying you need a soldering iron with a very fine tip (mine is 0.4mm I think, and the shaft is narrow enough to manoeuvre between everything), and also a steady hand!

If you want higher res (though unannotated) photos, PM me; I also made up a gif of the original mod, so if anyone wants to see the difference I can post it...

Tim

[Edit record:
edit 1: the 'EXP' header is 16-pin, not 20! Don't know what happened to my counting there!]
sandyb
thank you so much Tim we're not worthy

i hope this will be useful for all the other frac noisering owners who want to modify their modules.
rezzn8r
You are awsome, Tim. Thank-you very much for your time and brainpower.
solitaryzen
Thanks so much Tim - fellow member Cleaninglady is going to perform this mod for me It's peanut butter jelly time!

I notice the mod was done on the 8 jack version - mine is the 6 jack version, but hopefully the above notes will still apply....?
otoskope
Wow! Thanks heaps. Will try to do this to my three bananafied noiserings. Shouldn't be too man changes because of the bananas, I guess?
It's peanut butter jelly time!
/palle
Tim Stinchcombe
solitaryzen wrote:
I notice the mod was done on the 8 jack version - mine is the 6 jack version, but hopefully the above notes will still apply....?
Well having had a quick look at the front panel of the 6-jack version on the wayback machine, it looks like the 2 extra jacks were the 'noise out' and the 'main out',

[edit: gack! shouldn't have relied on my memory, if only from lunchtime - found a bigger picture, and the extra jacks are noise and 'ext chance', hence following comments about the main out are a load of guff - but the philosophy of checking the circuit local to the clock remain!]

which shouldn't really affect the area of the clocking circuitry, but adding the 'main' out could potentially have been quite a big change, so I'd recommend comparing the tracking on yours to some of my close-up pictures - if it looks identical then you are probably safe; however if anything has changed, it would be wise to check that the circuitry on yours really is the same (it shouldn't be too hard, as all the action takes place around that one op amp section).

Tim
Tim Stinchcombe
otoskope wrote:
Will try to do this to my three bananafied noiserings. Shouldn't be too man changes because of the bananas, I guess?
I've never worked with banana jacks before: the only thing I think that might be different is if there is no 'switching contact' on the bananas (?), in which case it may mean you have no 'normalled' connection from the aux out to the ext in (the one I unfortunately forgot to take a photo of!), and therefore don't have to remove it! Should be easy to spot if it is actually there!

Tim
solitaryzen
Tim Stinchcombe wrote:
solitaryzen wrote:
I notice the mod was done on the 8 jack version - mine is the 6 jack version, but hopefully the above notes will still apply....?
Well having had a quick look at the front panel of the 6-jack version on the wayback machine, it looks like the 2 extra jacks were the 'noise out' and the 'main out',

[edit: gack! shouldn't have relied on my memory, if only from lunchtime - found a bigger picture, and the extra jacks are noise and 'ext chance', hence following comments about the main out are a load of guff - but the philosophy of checking the circuit local to the clock remain!]

which shouldn't really affect the area of the clocking circuitry, but adding the 'main' out could potentially have been quite a big change, so I'd recommend comparing the tracking on yours to some of my close-up pictures - if it looks identical then you are probably safe; however if anything has changed, it would be wise to check that the circuitry on yours really is the same (it shouldn't be too hard, as all the action takes place around that one op amp section).

Tim


Thanks Tim - will have a good look before proceeding!
jenamu6
Thanks Tim.....Now I have to find the guts to actually perform this mod.
Tim Stinchcombe
jenamu6 wrote:
Now I have to find the guts to actually perform this mod.
Taking it slowly and steadily is the way to go, and I cannot stress enough how having the right tools for the job will determine how well it does go. This is the type of tip I mostly use on my iron, from this page:



- its ability to get into tight spots is self-evident, and also one of the reasons I have yet to see a Weller iron that looks like it might compete on equal terms, as all the Weller tips I've ever seen seem to be so short and stumpy I have a natural aversion to even picking the thing up, let alone attempting to solder with one. But it's horses for courses I guess.

Tim
sandyb
i'm going to sticky this thread for the benefit of any future wigglers who wish to perform the mod.

thanks once again to Tim for his time and skill Guinness ftw!

i'm looking forward to my noiserings returning!
marketingslime
Awesome Tim! Thanks so much...very helpful.
marketingslime
[quote="Tim Stinchcombe"]
jenamu6 wrote:




- its ability to get into tight spots is self-evident, and also one of the reasons I have yet to see a Weller iron that looks like it might compete on equal terms, as all the Weller tips I've ever seen seem to be so short and stumpy I have a natural aversion to even picking the thing up, let alone attempting to solder with one. But it's horses for courses I guess.

Tim


Tim,

What temp setting do you usually use with this tip? Do you have a particular solder preference?

Thanks,
Slime
Tim Stinchcombe
marketingslime wrote:
What temp setting do you usually use with this tip? Do you have a particular solder preference?
I have an Ersa RDS80 soldering iron:

http://www.ersa.com/art-0rds80-358-1997.html

- having bought one for my use at work, I was so impressed with it I bought one for my personal use at home. For leaded solder I have it set to 360C, which does for most work, unless I'm working with something that wicks the heat away, and it is then an easy matter to dial in another 10 degrees or so to give it a little boost. (But that said, I have no idea what the actual tip temperature is - I assume the temp sensing device is some way away from the end of the heating element - and so what you need will depend on the exact type of iron that tip is actually used on!)

As for solder, we used to use this stuff at work for small surface-mount devices (it is thin, 0.4mm diameter!) before everything went lead-free, and I bought a reel for myself:

http://uk.rs-online.com/web/p/solders/4430578/?searchTerm=4430578

but as you can see RS certainly don't sell it any more, and I think it is likely it is not even made any more - it is 'Alpha FT-2002 rosin free Sn63/Pb37, single core 1.4% flux content' made by Alpha/Cookson Electronics:

http://alpha.cooksonelectronics.com/Products/Cored-Wire/FT-2002-Rosin- Free

(and actually the pdf 'Technical bulletin' on that page suggests that lead/tin is maybe still around...).

For more normal through-hole work I bought a reel of the same stuff but with a larger diameter, 0.75mm:

http://uk.rs-online.com/web/p/solders/4430562/?searchTerm=4430562

(and I probably should add that a lot of my decision was based on the fact that it doesn't give off lots of nasty smelling fumes like some solders do!). At my current rate of usage, these two reels are going to last many, many years!

Tim
cleaninglady
I just finished this mod for solitaryzen.
Much more nerve racking doing it on someone else's module i must say...

Didn't have any solder smaller than 0.7 and my Soldering Iron tip is 1.4mm but i managed.

You need a really steady hand.

I ended up using the 10th pin of the Empty Socket at 'EXP' as i was a little wary of soldering the TL074 pin 9 with such a large Solder tip. (Thanks Tim for the advice).

Just soldered the wire straight to the socket conductor.

I used a hole punch to get the drill starting point for the hole in the panel and drilled it with 3mm then a 5mm bit.

Be very careful when soldering wires to the SMD components and gentle when soldering the switch. They are delicate and you can easily kill the switch by melting the housing around the conductors causing them to shift and the switch to malfunction or just not work at all.

I don't really recommend the size of solder tip i used but i'm just showing it has been done with regular gear.

Be brave and give it a go.
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