Search found 1212 matches

by Scruffie
14 Sep 2020, 23:19
Forum: Vintage Stompbox Corner ( ... - 1975)
Topic: EHX Bad Stone
Replies: 14
Views: 1631

Re: EHX Bad Stone

I provided you with a potential depth mod in another thread, you even thanked me by PM at 10:24 so why are you asking for one again at 10:26? I already told you via PM that if you want a phaser with a depth mod, this probably isn't the one to try it on but you have something to try. I think my suspi...
by Scruffie
13 Sep 2020, 21:09
Forum: Ready-To-Build Effect Projects
Topic: EH Bad Stone Revisited
Replies: 59
Views: 5691

Re: EH Bad Stone Revisited

I haven't simulated or tested this in any fashion and I'm not keen on how it's done but it's the simplest way I can think of and best you'll get out of me. B100k might not be the best value to use.
by Scruffie
05 Sep 2020, 11:00
Forum: Boutique Stompboxes dissected...
Topic: Pigtronix - Mothership
Replies: 19
Views: 5061

Re: Pigtronix - Mothership

I bought one of these (SMD) and traced it - it was hell. It is a multilayer board and there are signal traces on the inner layers, not just ground and power. The layout is such a spider-on-LSD affair that I have to think it was done on purpose to confuse this community. 😀 It took me quite a bit of ...
by Scruffie
13 Aug 2020, 11:51
Forum: Modern Stompbox Effects (1975 - ...)
Topic: Chorus 690 clock distorted output, not pulse
Replies: 15
Views: 566

Re: Chorus 690 clock distorted output, not pulse

So it's been determined the clock is fine but where are your voltages? Could be a problem in the audio path.
by Scruffie
04 Aug 2020, 14:51
Forum: Pedal Debugging & Troubleshooting Support
Topic: Vintage EHX Small Clone MINI-CHORUS SAD1024 Help please
Replies: 23
Views: 1512

Re: Vintage EHX Small Clone MINI-CHORUS SAD1024 Help please

My hopefully final questions: I guess when I box it all back up the 2N4340 needs to be back in there with the original switching? If (big if) the 2N430 is bad would that have effected the SAD1024 giving low output voltages? lift one leg of the 10k coming from the same place to make sure nothing fur...
by Scruffie
29 Jul 2020, 14:28
Forum: Pedal Debugging & Troubleshooting Support
Topic: Vintage EHX Small Clone MINI-CHORUS SAD1024 Help please
Replies: 23
Views: 1512

Re: Vintage EHX Small Clone MINI-CHORUS SAD1024 Help please

Well seeing as the 2N5087 collector should be grounded, I'd say there's still a mistake :)

4V for the MN3007 input was just an average expected voltage, it wont be exactly that as the chip will have its own individual bias point.
by Scruffie
28 Jul 2020, 10:13
Forum: Modern Stompbox Effects (1975 - ...)
Topic: EHX - Riddle QBalls VCF
Replies: 33
Views: 8986

Re: EHX - Riddle QBalls VCF

uncleboko wrote: 28 Jul 2020, 09:32 What can LM2901 do that LM339 can't?
https://www.ti.com/lit/ds/symlink/lm290 ... 252FLM2901

Still operate at wider temperature extremes.
by Scruffie
26 Jul 2020, 20:34
Forum: Modern Stompbox Effects (1975 - ...)
Topic: EHX - Riddle QBalls VCF
Replies: 33
Views: 8986

Re: EHX - Riddle QBalls VCF

So the Start/Stop/Attack/Decay 'core' uncleboko was after must be formed with the 4066 & Quad Comparator.

Interesting rail splitter chip too.
by Scruffie
24 Jul 2020, 16:56
Forum: Pedal Debugging & Troubleshooting Support
Topic: Vintage EHX Small Clone MINI-CHORUS SAD1024 Help please
Replies: 23
Views: 1512

Re: Vintage EHX Small Clone MINI-CHORUS SAD1024 Help please

You must have made a mistake in your 3007 conversion, what voltage do you get on the 2N5087?
by Scruffie
24 Jul 2020, 13:19
Forum: Pedal Debugging & Troubleshooting Support
Topic: Vintage EHX Small Clone MINI-CHORUS SAD1024 Help please
Replies: 23
Views: 1512

Re: Vintage EHX Small Clone MINI-CHORUS SAD1024 Help please

The bias :)

Pin 3 is the input, its voltage is adjusted by the bias trim, the output pins 7 & 8 track the input voltage.
by Scruffie
21 Jul 2020, 17:06
Forum: Modern Stompbox Effects (1975 - ...)
Topic: DOD - 460 Mini-Chorus [schematic]
Replies: 34
Views: 16982

Re: DOD - 460 Mini-Chorus [schematic]

You will keep noise down at the expense of headroom by increasing the input level yes, but that might be acceptable depending on your guitar and playing style, especially if you run at a higher supply voltage. But, whatever change you make to the input op amp to increase gain, you have to perform on...
by Scruffie
19 Jul 2020, 12:39
Forum: Pedal Debugging & Troubleshooting Support
Topic: Vintage EHX Small Clone MINI-CHORUS SAD1024 Help please
Replies: 23
Views: 1512

Re: Vintage EHX Small Clone MINI-CHORUS SAD1024 Help please

You said your LM358 was producing a varying triangle wave on your scope before? It should have been fine. Yes... those are... bad and hot chips generally aren't a good sign. Where did you source the chip from? Take the MN3007 out and take the voltages on it again, also, I realise Pin 1 on the MN3007...
by Scruffie
17 Jul 2020, 18:56
Forum: Pedal Debugging & Troubleshooting Support
Topic: Vintage EHX Small Clone MINI-CHORUS SAD1024 Help please
Replies: 23
Views: 1512

Re: Vintage EHX Small Clone MINI-CHORUS SAD1024 Help please

Didn't take it that way :) more speaking out loud for any others to check my thought processes in case I overlooked something, I'm not infallible!

If the new voltages check out as above, an audio probe might be the way to go next.
by Scruffie
17 Jul 2020, 17:10
Forum: Pedal Debugging & Troubleshooting Support
Topic: Vintage EHX Small Clone MINI-CHORUS SAD1024 Help please
Replies: 23
Views: 1512

Re: Vintage EHX Small Clone MINI-CHORUS SAD1024 Help please

What are the voltages on the MN3007? Going from your previous voltages, you should expect to see something in the region of. 1. 8.5 2. 4.25 3. 4 4. 0 5. 0 6. 4.25 7. 4.5 8. 4.5 A BBD requires the correct power supply voltages, a correct input bias voltage, anti-phase clock signals and a source follo...
by Scruffie
10 Jul 2020, 10:07
Forum: Pedal Debugging & Troubleshooting Support
Topic: Vintage EHX Small Clone MINI-CHORUS SAD1024 Help please
Replies: 23
Views: 1512

Re: Vintage EHX Small Clone MINI-CHORUS SAD1024 Help please

You are everywhere it seems lol. Should we just continue on here? Like a bad itch. Okay, if you're getting modulating square and triangle from the 358 that changes with rate, that's your LFO working fine, you have a square from the 4047 pins 10 & 11 which is your clock pulse at around IIRC 70-120kH...
by Scruffie
09 Jul 2020, 22:16
Forum: Pedal Debugging & Troubleshooting Support
Topic: Vintage EHX Small Clone MINI-CHORUS SAD1024 Help please
Replies: 23
Views: 1512

Re: Vintage EHX Small Clone MINI-CHORUS SAD1024 Help please

Seems like the wet signal is lost somewhere, so you need to scope or audioprobe the signal in the delay line (from pin 1 of the first opamp through the 1µF cap, and up to 2N4340 and 27k resistor.) Could be a bad FET, bad transistors, opened resistor...... The SAD is not the likeliest of all then. I...
by Scruffie
01 Jun 2020, 17:17
Forum: Modern Stompbox Effects (1975 - ...)
Topic: EHX - Micro Synth XO Version [schematic]
Replies: 103
Views: 53298

Re: EHX - Micro Synth XO Version [schematic]

Due to my morality and EH's sue-happy nature I plan on providing PCBs and OTAs for a clone of the older version I'm calling the Retro Synth. That along with a couple other projects will be released later this year. The newer version is still in my horizon. Just not perusing it while I have sources ...
by Scruffie
16 Mar 2020, 01:45
Forum: DIY Stompbox designs
Topic: Clarinot Env Control Circuit Daughterboard (Schem & Vero)
Replies: 9
Views: 2093

Re: Clarinot Env Control Circuit Daughterboard (Schem & Vero

The 4007 is 3 pairs of complementary MOSFET's, the Snazzy is using one as a variable resistor but you could hook up the spare 2 sets as inverters and use them as input and output buffers or whatever you wanted inverters for.
by Scruffie
12 Mar 2020, 23:41
Forum: Pedal Debugging & Troubleshooting Support
Topic: TC Stereo Chorus/Flanger voltages
Replies: 6
Views: 580

Re: TC Stereo Chorus/Flanger voltages

As usual I do agree with Fender3D but, if you post your voltages, it might be possible to spot something.