New vero layout: ProCo RAT

cathexis · February 13, 2009, 04:54:36 AM

Hi,
After a recent request I posted a veroboard layout of the original 80:s RAT in my gallery - no mods, no frills, just the classic dist box. The layout will fit in a b-sized box with a little work. I posted a sound clip as well.

http://www.aronnelson.com/gallery/main.php/v/cathexis/

LARS

kurtlives · February 15, 2009, 03:35:16 PM

The output buffer dosent seem right. The source is tied to 9V+ while the drain has no connection to 9v+ yet the signal comes out of it. Maybe your using some FET with a wonky pinout?

Renegadrian · February 16, 2009, 05:37:17 PM

Also you should point out that there are some hidden cut tracks!!!

I magnified your layout, and I see trace cuts under
R3
R9
C11

Also, is it verified?! Please tell me!!!

kurtlives · February 16, 2009, 05:38:51 PM

In another thread he told me it was verified.

I thought the cuts were clear...there is the other boards underneath the main showing them.

Renegadrian · February 16, 2009, 05:47:56 PM

Uh sorry Chris - midnight madness here...didn't see the whole image...

now off to bed then...

cathexis · February 16, 2009, 11:33:44 PM

Quote from: kurtlives on February 15, 2009, 03:35:16 PM
The output buffer dosent seem right. The source is tied to 9V+ while the drain has no connection to 9v+ yet the signal comes out of it. Maybe your using some FET with a wonky pinout?

Nope, no wonky pinouts, AFAIK. Use a socket and twist the pins around, see if it matters. Sometimes it doesn't, and someday I intend to find out why.

Quote from: Renegadrian on February 16, 2009, 05:37:17 PM
Also, is it verified?! Please tell me!!!

All my layouts are verified to sound at least as good as the sound clip right next to it.

LARS

grathan · March 29, 2009, 08:53:10 PM

Thanks for the layout. Can someone please tell me if the polarity of c8, c6, c4, c3, c10, c13 all have the negative side facing downwards?

foxfire · March 29, 2009, 09:25:33 PM

Quote from: grathan on March 29, 2009, 08:53:10 PM
Thanks for the layout. Can someone please tell me if the polarity of c8, c6, c4, c3, c10, c13 all have the negative side facing downwards?

that seems correct, the negative sides are down.

Altec · March 29, 2009, 10:33:16 PM

Maybe this is the kick in the pants I need to make a rackmount Rat like the R2DU.

grathan · April 23, 2009, 04:41:06 PM

Quote from: kurtlives on February 15, 2009, 03:35:16 PM
The output buffer dosent seem right. The source is tied to 9V+ while the drain has no connection to 9v+ yet the signal comes out of it. Maybe your using some FET with a wonky pinout?

I'm having trouble with getting this to work. perhaps the pinout is wrong on the jfet? Has anyone sucessfully made this circuit?

http://www.aronnelson.com/gallery/main.php/v/cathexis/Veroboard+Layouts/ProCo+RAT/ProCo+RAT.JPG.html

IvIark · April 23, 2009, 08:44:11 PM

Looks wrong to me. The 2N5458 I have are gate, source, drain (from top to bottom with the flat side to the right as shown in the vero layout) whereas the layout seems to be source, drain, gate. But even that doesn't correct it as the layout shows both R12 and C13 connected to the gate which doesn't tie in with the 80s Rat schematic I have. I assume is a component numbering difference

kurtlives · April 23, 2009, 08:59:45 PM

Quote from: grathan on April 23, 2009, 04:41:06 PM
Quote from: kurtlives on February 15, 2009, 03:35:16 PM
The output buffer dosent seem right. The source is tied to 9V+ while the drain has no connection to 9v+ yet the signal comes out of it. Maybe your using some FET with a wonky pinout?

I'm having trouble with getting this to work. perhaps the pinout is wrong on the jfet? Has anyone sucessfully made this circuit?

http://www.aronnelson.com/gallery/main.php/v/cathexis/Veroboard+Layouts/ProCo+RAT/ProCo+RAT.JPG.html

The pinout is wrong, I was looking my populated vero over last night. Some changes need to be made to use a standard 2N5458 with normal pinout.

cathexis · April 25, 2009, 12:02:09 PM

This layout is now corrected. V+ now goes to drain. But as I noted in an earlier post, there is no audible difference here if you switch drain and source. I have tried both ways.

I did find another mistake, though, as noted by IvIark. The + end of C13 (1uf) needs to be connected to source, not to gate, the - end of the same cap to volume pot lug 3. This is also corrected. Component numbering obviously does not correspond to any schematic whatsoever.

LARS

IvIark · April 26, 2009, 06:30:52 AM

Thanks for the update!

Quote from: cathexis on April 25, 2009, 12:02:09 PM
Component numbering obviously does not correspond to any schematic whatsoever.

Right. I wondered if your layout and the schematic I have were based on component numbering on the original board.

80k · April 30, 2009, 03:35:47 PM

cool layout, thanks! It is smaller than Torchy's vero layout, which is nice.

I did notice an interesting thing. Coming out of Pin 7 of the Opamp, you have a jumper going to the top strip (beneath the opamp). And then you have a cut next to that jumper. And then you have a jumper coming do the drain of the FET. But the drain of the FET is on the same strip as Pin 7, which means that you just jumpered it right back to where it should be. It seems you can get rid of one of the jumpers and simply remove the cut. Hopefully i'm looking at this right?

cathexis · May 02, 2009, 06:10:24 PM

Quote from: 80k on April 30, 2009, 03:35:47 PM
cool layout, thanks! It is smaller than Torchy's vero layout, which is nice.

I did notice an interesting thing. Coming out of Pin 7 of the Opamp, you have a jumper going to the top strip (beneath the opamp). And then you have a cut next to that jumper. And then you have a jumper coming do the drain of the FET. But the drain of the FET is on the same strip as Pin 7, which means that you just jumpered it right back to where it should be. It seems you can get rid of one of the jumpers and simply remove the cut. Hopefully i'm looking at this right?

Correct! This is the result of the correction above, I think. I posted this layout as on a request, but it's an old one, and there were some issues. I should stick to hand-made, I suppose. It should work alright now, and it is a righteous distortion, one of my favourites.
LARS

80k · May 02, 2009, 09:27:23 PM

Cool, the layout looks good now. I have verified it with the schematic. That unnecessary cut/double-jumper was the only thing I noticed (which isn't really a mistake, since it still works). Other than that, i think it's a good layout. I may build to it sometime this month, and will report back.

Renegadrian · May 07, 2009, 06:55:24 PM

Yes, I finished that damned rat, that layout is verified.
I think the FILTER is wired backwards, actually it darkens the tone if turned CW.
---
edit: Yes it is au contraire, under volume 3 there should be filter 1 and under it filter 2+3
---

I made one with the LUBE mod. It acts like a second gain knob, more or less...Is it a filter?
Also, I have a dpdt for Si and LEDs - maybe the dpdt doesn't work correctly but I get the same sound on both positions...
Any clues?!

cathexis · May 08, 2009, 12:01:22 AM

Quote from: Renegadrian on May 07, 2009, 06:55:24 PM
Yes, I finished that damned rat, that layout is verified.
I think the FILTER is wired backwards, actually it darkens the tone if turned CW.

The filter is a hi-cut, as on the original. Backwards, but in a correct way

Double check the wiring on that switch, It's real easy to go wrong there.

Thanks a lot for verifying this curse-ridden layout!

LARS

kristoffereide · May 08, 2009, 04:54:06 AM

could anyone post the final layout link? There are several in this topic, and I don't want to make the wrong one

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New vero layout: ProCo RAT