WSG Thank you!

Tronato · Posted: Thu Oct 04, 2007 2:04 pm Post subject:

Hello Blue Hell:

Since the cables that connect the Front Panel to the Printed Circuit Board are the closest I have seen to an octopus I would like to try to avoid soldering/unsoldering once the cables are connected again.
Since the I.C. has a socket, would carefully bending pin 12 so that it remains out of the socket have the same effect? After testing I would carefully bend it again into place. This for Voice B. For Voice A it would be pin 2... would these unconnected pins ruin the I.C. when power is applied?

Sounds crazy?

Thanks!

TRO

blue hell · Posted: Thu Oct 04, 2007 4:32 pm Post subject:

It's OK to bend out pin 12, when you set "Zaniness amount" to zero and "Wackiness" and "Wackyness too" both off ... shit where is WSWB going ... and DPSB, damn, those can carry signals as well, now I see why it's called what it is, this WSG Very Happy

Erm, it looks most like those are just labels not connected to anything .. so, yes, then it would probably be silent, bit I can't find quickly what those labels mean.

Cut out that resistor ! that works for sure Laughing

blue hell · Posted: Thu Oct 04, 2007 4:34 pm Post subject:

Tronato · Posted: Thu Oct 04, 2007 4:41 pm Post subject:

Hello again!

Those letters correspond to the cables that are coming from the Front Panel, a drawing of which is on the same page as the circuit if you're looking at Ray's WSG Web Page...

But I just found the most amazingly simple solution... it's so obvious that if it would've been a snake it would've bitten me!

I'll remove both resistors and attach them underneath the board... (LOL)...
that way the cables won't bother me!

What do you think?

TRO

blue hell · Posted: Thu Oct 04, 2007 4:47 pm Post subject:

Pehr · Posted: Fri Oct 05, 2007 2:08 am Post subject:

Tronato · Posted: Fri Oct 05, 2007 3:06 am Post subject:

Hello Pehr:

I assume that this should be done with the complete Front Panel (that is pots and switches) connected to the PCB, right?
Since they are currently disconnected my idea was to connect for example the 3 pots and the switch associated with the filter and then check with the signal tracer in the filter section if the annoying noise was present. If it wasn't the perform the same procedure with voice 1 and then with voice 2...
With what you are suggesting, how can I know what voltage should be present where?

Thanks

TRO

Pehr · Posted: Fri Oct 05, 2007 4:05 am Post subject:

Tronato · Posted: Fri Oct 05, 2007 4:47 am Post subject:

Hello again:

No I don't mean across C8, I mean across other points in the circuit...

Thanks!

TRO

Pehr · Posted: Fri Oct 05, 2007 6:20 am Post subject:

Scott Stites · Posted: Fri Oct 05, 2007 1:01 pm Post subject:

I'm curious:

What type of jacks are you using? 1/4", 3.5 mm, banana?

What type of cable are you using to connect to the amplifier (coaxial grounded, etc.)?

I just get the feeling reading through this that it is 60 cycle hum, regardless of whether it's battery powered or not. Connecting the AC/DC supply then touching the controls and hearing a difference is a real good clue right there.

If the jacks do not have a common ground with the amplifier, you're likely to get that. If it's a bare aluminum panel they're going to connect together through the panel, depending on the type of jack. If they don't have the ground they need, and it is not common to the amplifier, your panel could well act as a LF receiver tuned to our favorite station, 60 Hz Golden Oldies. If that's the case, I'd be really suprised you haven't received Wall of Voodoo as well (Mexican Radio). Maybe it's not in the bounce path over in Florida.....

Cheers,
Scott

Tronato · Posted: Fri Oct 05, 2007 5:56 pm Post subject:

Hello Scott:
I was wondering if you were ever going to read this post!
Once I get my WSG working I'll get into your Vactrol mods.

Now to business...

1.- I bought Ray's kit. It uses a 1/4 " jack.

2.- I connect to my amp with a standard guitar plug (1/4" plugs on both ends) coaxial cable which I use with my Electribe AE-1 with no problem whatsoever.

3.- There is a seamless continuity between the pots, switches, aluminum panel, PCB's ground and the audio jack's ring (signal on tip).

Thus said I'll invert the jack connection and see what happens.

Thanks!

TRO

Scott Stites · Posted: Sun Oct 07, 2007 7:31 am Post subject:

Hey Tronato,

Well, it was a shot in the dark. You can figure out pretty quickly if the jacks have the ground wired on the right lug if you have a spare jack. Just to double-check, you can plug a cable into this spare jack and check continuity of the ground of the cable to the ground lug on the jack and tip of the cable to the tip lug of the jack.

The positions of those lugs change from manufacturer to manufacturer, so it can happen. Very Happy

Take care,
Scott

RF · Posted: Sun Oct 07, 2007 1:27 pm Post subject:

OK -so here is another thought...

When you get it back together - if you find the noise is still there, I'd be interested to know if you hear it in headphones - not using an external amplifier, or connected to anything else...

Hopefully you will find the problem before then.... Smile

bruce

Tronato · Posted: Mon Oct 08, 2007 5:13 pm Post subject:

Hello!

HELP! I inverted the jack cables and it ruined my amp! Darn!

TRO

Scott Stites · Posted: Tue Oct 09, 2007 10:15 am Post subject:

Wuh-oh.

Tronato · Posted: Thu Oct 11, 2007 1:34 pm Post subject:

Howdy my friends!

Since we've been sort of silent lately here is a pic of the rewired Front Panel. I cut all cables 1 foot long and attached them to the panel.
This way I can troubleshoot the whole thing easier.
I chose the same Front Panel design suggested by Ray.

Next step: remove the two 1M resistors and attach one leg of each to their corresponding position (the one closest to the I.C.) UNDERNEATH the circuit board, then connect the circuit board to the Front Panel.

Coming to think about it, I'll attach those 2 resistors to the Experiment Kludge Area, and add a couple of switches in order to be able to select Voice A or Voice 2 or both... There you are! We have witnessed the birth of another simple MOD... TRONATO'S MOD!

Due credit must be given to BLUE HELL who suggested how to isolate the 2 Voices. His suggestion made me think about the Mod.

What do you think?

Hmmmm... now I have to figure out where will those 2 switches fit elegantly... GOT IT! There's enough space under the Voice B pots.

Now to the infamous Radio Shack to see if at least they have switches similar to the ones used so far...

Note the aluminum plate on which everything has been mounted.

Thanks!

TRO

PS: The ruined Amp post was a joke! (LOL).

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RF · Posted: Fri Oct 12, 2007 4:41 am Post subject:

Hey Tronato
Glad to hear the amp is OK. Hope the wsg project is coming along.
bruce

Tronato · Posted: Fri Oct 12, 2007 4:07 pm Post subject:

Hello again friends!

Well, we are getting there but everyday I convince myself that there is no way to make this project look nice... back 25 years ago when I used to breadboard and use universal printed circuit boards I was (and still am) of the belief that if the project looks nice it will most probably work.

In any case I'm almost done connecting the PCB and the Front Panel... the following pic shows the progress.

Thanks all for your help!

TRO

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Tronato · Posted: Sat Oct 13, 2007 10:06 am Post subject:

Hello!

Well I finished putting the WSG back together again...

Blue Hell:
Would you believe that it works just the same even with the 2 resistors disconected (R22 for Voice B and R5 for voice A)? It's like if they were not needed! So much for Tronato's Mod! (LOL). So then the signals reach the filter through some other path... probably R21 (VB) and R2 (VA).

The noise is still there (no reason why it should not be since nothing has changed). However at least I now know it's not coming from the filter because when I first turned it on I had forgotten to put the I.C. CD40106 (U1) back in it's socket and the noise was not present.

RF:
Listening to it through headphones is useless because the volume is very, very low, not enough to listen to low frequencies.

Next step before I throw this monster into the ocean is I'm going to substitute the CD40106 that came with the kit for a 74C14 I bought yesterday and see if anything changes.

Update: Substituted the I.C. and even if I have the impression that the 74C14 is more alive, the noise is still there...

Happy weekend!

TRO

blue hell · Posted: Sat Oct 13, 2007 11:09 am Post subject:

Tronato · Posted: Sat Oct 13, 2007 11:34 am Post subject:

Hello again:

I don't know if this will work but I am attaching a small 15 sec video of the wsg where you can hear the noise I'm talking about. All pots are at minimum even if it doesn't seem so...

Is this sound normal? I don't think so...

Thanks!

TRO

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RF · Posted: Sat Oct 13, 2007 12:51 pm Post subject:

OK - That's good to hear what you have been refering to, tronato.

The breadboard version I made of the simple WSG made a sound like that with certain combinations of the controls - don't ask me which ones, cause its all back in the parts box Smile

Is there any combination of the controls that makes it go away - regardless of wether they are "at minimum" or not?

It just sounds to me like two of the oscilators are just doing their own thing - you just need to tame them...

Tronato · Posted: Sat Oct 13, 2007 3:13 pm Post subject:

Hello again!

This is absolute madness...

I bent pins 2 - 4 - 6 of the CD40106 in order to isolate Voice A from the circuit and indeed this isolated it since the controls didn't affect the sound but the noise was still there...

So I put the pins back in their original position and proceeded to do the same for Voice B, that is pins 8 - 10 - 12 and the damn noise was still there!!!!!

Could it be the transistors? They are the only active components that I haven't substituted...

And who can explain what R5 and R22 are for? I disconnected them thinking I could isolate the Voices that way but everything works as if they were connected. Whether they are in the circuit or not everything works the same...

My girlfriend insists that I should throw the whole thing away!

Darn!

TRO

blue hell · Posted: Sat Oct 13, 2007 3:59 pm Post subject:

R5 and R22 mix the voices A and B into the filter. But, when S1 is closed sound can come in through R2 from voice A and likewise for voice B with S4 and R21. So when the resistors are out and the switches are in the correct position the thing should be silent.

When it's not silent either the switches S1 and/or S4 are set wrong or the filter oscillates. Try, with R5 and R22 "removed" all four possible combinations of S1 and S4, one out of four should be silent unless the switches are incorrectly wirded up or the filter oscillates.

When the filter oscillates presumably how it oscillates would be influenced R3, R31 and R32 - when that's not the case ... hmm, wouldn't know then.