Search found 214 matches

by Rocket Roll
07 Mar 2024, 13:39
Forum: Amplifiers
Topic: Fender Riviera Era Footswitch Layout and Fender 75 Hi/Lo and Standby Switch Layout
Replies: 0
Views: 165

Fender Riviera Era Footswitch Layout and Fender 75 Hi/Lo and Standby Switch Layout

Just got a Fender 75 amp. I've spent two whole working days restoring it to factory specs. To make future easier for someone, here are layouts - of a Riviera-Era footswitch (which works for all Riviera-era amps, see http://www.stratopastor.org.uk/strato/amps/prii/footswitch/footswitch.html) and of a...
by Rocket Roll
01 Feb 2024, 06:37
Forum: Pedal Debugging & Troubleshooting Support
Topic: EHX Vintage issues
Replies: 68
Views: 14060

Re: EHX Vintage issues

Went ahead and ordered a box of assorted caps, both electrolytic and ceramic to replace all of them. Once again, you're shotgunning. It rarely gets you anywhere, as I already told. But if you're going to do it, replace electrolytics first. It's one's best guess when it comes to "I have no pati...
by Rocket Roll
30 Jan 2024, 08:29
Forum: Pedal Debugging & Troubleshooting Support
Topic: EHX Vintage issues
Replies: 68
Views: 14060

Re: EHX Vintage issues

I need to revisit Ralf's page as he gives a lot of details that might lead to an answer. Bingo. You'd save yourself A LOT of trouble and A WHOLE LOT of writing if you only started from the beginning - finding the voltage measurements of a known good original and finding the calibration procedure. T...
by Rocket Roll
22 Jan 2024, 11:13
Forum: Pedal Debugging & Troubleshooting Support
Topic: EHX Vintage issues
Replies: 68
Views: 14060

Re: EHX Vintage issues

It's pretty complicated to replace SAD1024 with anything else in a circuit that is designed around SAD1024. There was a man who attempted to make a replacement board, but it used two MN3009 and a lot of SMD components: 01.webp Your best bet is to find a cheap old flanger that uses SAD1024 and works....
by Rocket Roll
15 Jan 2024, 10:46
Forum: Pedal Debugging & Troubleshooting Support
Topic: EHX Vintage issues
Replies: 68
Views: 14060

Re: EHX Vintage issues

Check for 18.0 V at pin 7 LM741. Check for 12 V (12.0 - 13.5 V) at pin 8 4558, pin 14 4013, pin 3 LM339. Check SAD1024 socket (remove SAD1024 first): pin 1: GND pin 2: input signal (x2 amplitude) pin 3: clock square wave pin 4: GND pin 5: 12 V pin 6: n/a (will be the output) pin 7: 12 V pin 8: clock...
by Rocket Roll
12 Jan 2024, 12:45
Forum: Pedal Debugging & Troubleshooting Support
Topic: EHX Vintage issues
Replies: 68
Views: 14060

Re: EHX Vintage issues

No offense, but seems to me you have taken the path of most expensive and complicated repair possible. Not to mention that you will no longer have an original PCB with original components, so that every and all value of that effect will be nulled. Testing non-working pedals is easy - you need some k...
by Rocket Roll
10 Jan 2024, 20:19
Forum: Pedal Debugging & Troubleshooting Support
Topic: EHX Vintage issues
Replies: 68
Views: 14060

Re: EHX Vintage issues

Maybe if someone can help me understand what I should be reading at the VR1 wiper I would appreciate it. The BIAS - adjust for maximum input signal amplitude without clipping at SAD1024 pin 6 or 12 (TP1*). The input amplitude should be greater than 1 V p-p. http://www.metzgerralf.de/elekt/stomp/mis...
by Rocket Roll
09 Nov 2023, 06:45
Forum: Original Tracer Layouts
Topic: MXR Dyna Comp - original tracer layout
Replies: 2
Views: 3049

Re: MXR Dyna Comp - original tracer layout

Thanks! But why is the R10 (in the factory schematic) 27K in your layout, 16K in the factory schematic (and 15K everywhere else)? I can understand 15K-16K variation, not a lot of difference there, but why 27K (that would be the resistor in parallel with .01 cap, coming from the third pin of the OTA)...
by Rocket Roll
27 Oct 2023, 06:13
Forum: Boutique Stompboxes dissected...
Topic: Keeley - Compressor
Replies: 32
Views: 16380

Re: Keeley - Compressor

Here are the guts of the Keeley Compressor Plus.
by Rocket Roll
20 Sep 2022, 06:41
Forum: Pimp-My-Cheap-Pedal
Topic: Dunlop - Cry Baby GCB-95: how to improve it for cheap
Replies: 235
Views: 225342

Re: Dunlop - Cry Baby GCB-95: how to improve it for cheap

Forget about Teese wahs and all the bullshit about specially manufactured parts etc., here is how to make any standard cry baby wah sound much better. :wink: So here's an old Dunlop JH-1 which was modded with a Halo inductor replica from Banzai and a different set of trannies (nothing fancy, just s...
by Rocket Roll
26 Jan 2022, 07:40
Forum: Boutique Stompboxes dissected...
Topic: Zvex - Box of Rock [traced]
Replies: 383
Views: 168963

Re: Zvex - Box of Rock [traced]

Leaving here a wiring schematic:
01.jpg
by Rocket Roll
19 Jul 2020, 20:19
Forum: Boutique Stompboxes dissected...
Topic: Keeley - Java Boost
Replies: 37
Views: 13802

Re: Keeley - Java Boost

If you cannot set the right values with the potentiometers the OC44 does not have the right values for HFE (gain) and leakage current. Oddly enough, this OC44N tested fine, although with a smaller hFE than it would be ideal - about 60. I think I'll go with R. G. Keen's wisdom for now - it's simply ...
by Rocket Roll
19 Jul 2020, 11:05
Forum: Boutique Stompboxes dissected...
Topic: Keeley - Java Boost
Replies: 37
Views: 13802

Re: Keeley - Java Boost

Ok, here's one for the column "I don't know why it works (but I like it)". I've build a Keeley Java Boost using johnk's PCB, and one of the new Mullard OC44's that Banzai sells: KJB OC44.jpg However, for the life of me I can't get the voltages under cca 9V. The ones I've decided to settle ...
by Rocket Roll
30 Mar 2020, 18:08
Forum: Pimp-My-Cheap-Pedal
Topic: Dunlop - Cry Baby GCB-95: how to improve it for cheap
Replies: 235
Views: 225342

Re: Dunlop - Cry Baby GCB-95: how to improve it for cheap

What effect on the sound does bringing the 4.7uf down to 4uf have? It's subtle, but it's worth it if you: a) like the sound of the original Italian Jens b) play loud (preferably in front of people, and with other people's help) and can really hear (and feel) what's going on with your sound c) don't...
by Rocket Roll
15 Jan 2019, 14:29
Forum: Amplifiers
Topic: Capacitors in Mesa Boogie Dual Rectifier
Replies: 25
Views: 12434

Re: Capacitors in Mesa Boogie Dual Rectifier

Actually, they have a higher failure rate than electrolytics, all of the data suggests. One of the possible reasons for using them is distortion. When placed on signal path, they tend to introduce non-linearities, the sonic signature of which is very much respected in both pro-audio (Rupert Neve) an...
by Rocket Roll
28 Nov 2018, 10:43
Forum: Modern Stompbox Effects (1975 - ...)
Topic: Dunlop - JBF-3 Joe Bonamassa Fuzz Face [schematic]
Replies: 162
Views: 127222

Re: Dunlop - JBF-3 Joe Bonamassa Fuzz Face [schematic]

Rocker83 wrote:Can anyone decipher the correct values and types of resistors and the capacitors in this JBF-3?
01.jpg
by Rocket Roll
03 Oct 2018, 17:15
Forum: DIY Projects
Topic: Fred Briggs - Super OCD
Replies: 65
Views: 23538

Re: Fred Briggs - Super OCD

I always use ICL7660 S CPA, as Bill Finnegan have, as should you and as should everybody. The charge pump frequency is moved to 20 kHz and above with that model (I forgot the exact value), so that the whine doesn't interfere with your guitar signal. It's safe to say that, whenever you see MAX1044 or...
by Rocket Roll
01 Oct 2018, 08:22
Forum: DIY Projects
Topic: Fred Briggs - Super OCD
Replies: 65
Views: 23538

Re: Fred Briggs - Super OCD

Here are the working voltages (I've used deeno's PCB).
FredBriggsOCDWorkingVoltages (1).jpg
FredBriggsOCDWorkingVoltages (1).jpg (17.44 KiB) Viewed 4258 times
FredBriggsOCDWorkingVoltages (2).jpg
FredBriggsOCDWorkingVoltages (2).jpg (13.36 KiB) Viewed 4258 times
by Rocket Roll
05 Jul 2018, 05:06
Forum: Pedal Debugging & Troubleshooting Support
Topic: Rat Sounds Wrong
Replies: 16
Views: 1923

Re: Rat Sounds Wrong

I think that's ok. By all means check the other values too.
Multi-RAT.png