To "stobiepole" Re: Gristleizer

bryantabuteau · August 09, 2006, 06:43:53 PM

Quote from: Rob Strand on August 08, 2006, 11:54:03 PM
Here's a higher resolution scan of the veroboard from the orginal article (which wasn't clear on the previous scans),

Cheers

Shame I just spent an hour or two last night mapping out all the track cuts from comparing with the schem

at least I can check my work now

stobiepole · August 09, 2006, 09:29:02 PM

Me too...but at my level of experience it's all good practice.

I'd recommend looking for the book 'Wreckers of Civilisation', which is a biography of the band members. It's a fantastic read.

bryantabuteau · August 09, 2006, 09:38:10 PM

I'll check it out. I'm a big fan of TG, Psychic TV, Coil etc all the projects that spawned from that movement. Read a great book recently with interviews of early industrial pioneers called "Tape Delay : Confessions from the Eighties Underground" . Had heaps of interesting stuff, and GREAT artists.

9 volts · August 10, 2006, 05:40:33 AM

Hey does anyone know of a transistor substitute for the bc187. It's a pnp, I'm wondering if a 2n3906 may work. The bc187 seems a little difficult to find. Thanks.

Arn C. · August 10, 2006, 02:43:59 PM

Yes the 2n3906 is a direct substitute!!!!

Peace!
Arn C.

stobiepole · August 17, 2006, 05:54:09 AM

Okay, I finished putting my Gristleizer together, plugged in a couple of batteries, and then...nothing. Worse than nothing - one of the batteries started to overheat and the casing started to split. Which seemed appropriate, somehow...

Any idea why that might happen? I think I'll just start again rather than try and debug it. I don't really want to kill any more batteries.

Chris

Rob Strand · August 17, 2006, 06:02:34 AM

Put a 100 ohm resistor in series with the +ve rail to limit the current.

Measure the supply rail on the circuit side of the 100ohm to get an idea what is going on. I suspect a short. Probably because one of the vero cuts has been missed (either by you or on the original layout). You will have to go over it by eye - there's no easy way.

To save batteries you could also run from a wall-wart/plug pack, leaving the 100ohm in place.

Once you have managed to clear the short on the power rails try removing the 100ohm resistor.

I don't have the circuit with me but if that circuit runs from a dual supply ie. +/-9V then put resistors in both rails.

stobiepole · August 17, 2006, 06:47:59 AM

Arrrgh...I think that's a job for a new day.

Has anyone managed to make a working Gristleizer from this layout?

Chris

9 volts · August 18, 2006, 09:30:49 AM

I'm in the process of getting one of these together. Could i substitute 1n4148 or 1n914a diodes for the oa47 diodes as they seem hard to find? Any other more appropriate sub's for 0a47?
Thanks

stobiepole · August 18, 2006, 07:56:29 PM

1n34a's are probably closest...otherwise a Shottky diode might be closer than a regular Si diode.

9 volts · August 19, 2006, 12:29:02 AM

I've put this together and for the most part it works. The 4 way switch offers a variety of tremoloish sounds and I'm not having any trouble with the batteries. (note both the diodes have a + written on the negative end, check the schematic) ps I'm using 1n34 diodes.

*But when I switch from 'envelope' to 'filter' I don't get a sound coming through at all. So I've still got some problems.
Any help appreciated, Thanks

stobiepole · August 19, 2006, 12:57:56 AM

I would never have spotted that one.

That's all good news. The layout is at least semi-working (or at least more working than I've managed to get it). I'll keep at it.

I was going to give up for a while. I've just had three failures in a row and I'm feeling low...Maybe it's time to start etching my own PCBs.

9 volts · August 19, 2006, 10:39:58 AM

Has anyone built one of these and had success?
I've re checked it and it seems all correct. I'm currently trying to audio probe the circuit board. any suggestions appreciated.

ps Stobiepole - pcb boards in my opinion are the way to go with projects this size.

stobiepole · August 19, 2006, 10:49:37 AM

In which case, there's a PCB layout on the Geofex site. I'm thinking I might give it a go...

It's not verified, unfortunately.

http://geofex.com/Article_Folders/gristlecheck.PDF

Dan N · August 19, 2006, 02:57:51 PM

Quote from: 9 volts on August 19, 2006, 12:29:02 AM*But when I switch from 'envelope' to 'filter' I don't get a sound coming through at all.

Check your switch wiring. Do you have both poles connected? I don't know if it would make any difference, but there is a hard to see trace cut just left of pin 1 at IC5.

Hang in there guys, no reason the vero should not work!

stobiepole · August 19, 2006, 07:26:05 PM

Okay. I've tallied the number of trace cuts that appear on each row of the veroboard. Starting from the top, I get:

0,0,3,6,4,4,5,2,2,2,0,2,0,6,4,3,3,4,2,1,3,5,1,0,0,0

Somebody want to check and see if they get the same results?

I actually think that RG's PCB looks pretty good - certainly smaller and neater than the vero version.

9 volts · August 19, 2006, 09:27:44 PM

My trace cuts are the same as yours
0,0,3,6,4,4,5,2,2,2,2,0,2,0,6,4,3,3,,4,2,1,3,5,1,0,0,0
from the top down

stobiepole - Rg's pcb does look good but I read in an earlier discussion about this effect that more tickling may be heard with ic's that aren't single op amps. (do a search)
Also I noticed that the pcb layout differs for transistor2 (check out where diode 2 is situated) .Maybe it is designed for a different jfet.

I'm going to check out my switch wiring again. It seems odd that half of the effect is working. So far the sounds I'm getting are fun. If I audio probe the first 3 ic's I have a pulse sound that speeds up when I turn the speed pot.

stobiepole · August 19, 2006, 10:34:40 PM

I'm going to rebuild my vero version - I think I probably blew something and I'd rather do it all over than spend forever trying to find the problem (something I suck at anyway)...

In some of the old discussions, there was something about an incorrect power lead going to a pot. That might be worth checking...

9 volts · August 20, 2006, 02:34:57 AM

Quote from: stobiepole on August 19, 2006, 10:34:40 PM
I'm going to rebuild my vero version - I think I probably blew something and I'd rather do it all over than spend forever trying to find the problem (something I suck at anyway)...

In some of the old discussions, there was something about an incorrect power lead going to a pot. That might be worth checking...

Could you please send the link as I'm having trouble finding it. I'm having trouble trying to find this error in the layout also.
Steep learning curve to say the least..........I think it would be worth getting this effect sussed out as it's obviously got alot of potential

Dan N · August 20, 2006, 03:47:36 AM

Here's the schematic from the old gristle site. It does not use the transistor in the power supply and uses a slide switch for bypass. Notice the easy to read switch wiring diagrams on the bottom. The numbers correspond to your vero builds.

http://users.rio.com/senorris/auction/dec/gristleizerpcd.gif

A couple things to remember- the trim pot VR6 is volume. If you test with that sucker turned down, you won't hear anything! VR5 is bias. It needs to be adjusted or you wont have any effect from the LFO.

I went line by line on the vero and could not find anything wrong.

Good luck!

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To "stobiepole" Re: Gristleizer