Search found 957 matches

by Manfred
Today, 11:22
Forum: Pedal Debugging & Troubleshooting Support
Topic: DMB Lexi pedal, gated fuzz!?!?!
Replies: 11
Views: 288

Re: DMB Lexi pedal, gated fuzz!?!?!

I intend to create a PCB clone, but I should know what is behind the green mass.
Is it possible to remove this mass?
by Manfred
23 Jun 2020, 00:03
Forum: Vintage Stompbox Corner ( ... - 1975)
Topic: Morley Wah Repair (seems to been have modded for 240V).
Replies: 4
Views: 197

Re: Morley Wah Repair (seems to been have modded for 240V).

Here the schematic: MorleyPWB_schematic.jpg I have had several contacts with Scott from Morley when I had repair problems with the pedals. I also had a pedal with LED LDR couplers on the workbench that didn't react well. He explained to me that when the pedal was not in use for a long time the LDRs ...
by Manfred
21 Jun 2020, 23:50
Forum: Amplifiers
Topic: How to improve tube amplifier tone by changing one part
Replies: 101
Views: 5147

Re: How to improve tube amplifier tone by changing one part

As I previously stated - I am not interested in proof, recordings measurements etc. Well then why would anyone be interested in trying it out? Quod gratis asseritur, gratis negatur. I think this forum is, among other things, a platform to share ideas and experiences in our field of interest and als...
by Manfred
21 Jun 2020, 14:48
Forum: Boutique Stompboxes dissected...
Topic: Keeley Darkside
Replies: 3
Views: 397

Re: Keeley Darkside

...i don't want to be pessimist, but tracing this pedal with only some pics (even if nice detailed pics), would be very hard; i don't say impossible, but hard. it would be difficult with the pedal in our hands as well. I agree, in addition to that, as you can see on the picture with the solder side...
by Manfred
21 Jun 2020, 02:30
Forum: Modern Stompbox Effects (1975 - ...)
Topic: T-Rex - Hobo Drive [schematic]
Replies: 12
Views: 550

Re: T-Rex Hobo Drive [schematic]

Click on the pic ...it will open a higher resolution pic so you can see it much better and you can easily see the values. At least it worked for me...actually very clear and easy to read ...and I'm using my phone... Thanks, I had already done so, but now I copied the picture and pasted it into a gr...
by Manfred
20 Jun 2020, 10:03
Forum: Modern Stompbox Effects (1975 - ...)
Topic: T-Rex - Hobo Drive [schematic]
Replies: 12
Views: 550

Re: T-Rex Hobo Drive [schematic]

Thanks, but the component values are bad or not visible at all.
Could you please take four or more shots or scans of the schematic?
by Manfred
20 Jun 2020, 09:48
Forum: Modern Stompbox Effects (1975 - ...)
Topic: Hofner - Fuzz (2009, IC-based) [schematic]
Replies: 17
Views: 3148

Re: Hofner - Fuzz (2009, IC-based) [schematic]

Pin 1 is not connected to the circuit, it is the connector for the offset compensation which is not used here. The measured value of 0V is ok, only a few millivolts should be measured here. The same applies to pin 5. Pin 8 is without function and not connected to the internal circuit of the op-amp. ...
by Manfred
19 Jun 2020, 00:01
Forum: Modern Stompbox Effects (1975 - ...)
Topic: Hofner - Fuzz (2009, IC-based) [schematic]
Replies: 17
Views: 3148

Re: Hofner - Fuzz (2009, IC-based) [schematic]

The transistors have tolerances so that different voltages can be measured at the Source pin, but I think the value of 0.74 Volt you measured is too high. In a test circuit I measured a voltage of about 0.49 Volt for the circuit with a gate resistor of 1 Megaohm and a source resistor of 10 Kiloohm. ...
by Manfred
17 Jun 2020, 17:20
Forum: Vintage Stompbox Corner ( ... - 1975)
Topic: Univox - Superfuzz [schematic]
Replies: 439
Views: 214417

Re: Univox - Superfuzz [schematic]

Only a year late on seeing this, but it was a Peak Atlas DCA55 which uses a test current of 2.5mA.
Thanks, did you also measure the voltages on the transistor terminals in the original pedal?
by Manfred
17 Jun 2020, 01:57
Forum: Vintage Stompbox Corner ( ... - 1975)
Topic: SolaSound - Tonebender 1971 [schematic]
Replies: 30
Views: 10093

Re: Tonebender MKIV - Mod feedback wanted! [schematic]

I think it would be a pity to modify the original pedal, I would personally leave it as it is and make a new one with my sound preferences.
by Manfred
12 Jun 2020, 22:39
Forum: Modern Stompbox Effects (1975 - ...)
Topic: Hofner - Fuzz (2009, IC-based) [schematic]
Replies: 17
Views: 3148

Re: Hofner - Fuzz (2009, IC-based) [schematic]

What are the DC voltage values at pin 3 and pin 6 of the operational amplifier and at the source terminal of the J201?
by Manfred
11 Jun 2020, 22:51
Forum: Modern Stompbox Effects (1975 - ...)
Topic: EHX - Hog's Foot / Mole - Bass Booster [schematic]
Replies: 3
Views: 608

Re: EHX - Hog's Foot / Mole - Bass Booster [schematic]

I made this PCB clone after the above draft by Bill Lawrence, I'm sure he wouldn't mind. I had the privilege of meeting him in 1983. We met at a Dynachord event at the Frankfurt Music Fair. He was a nice person with a tremendous knowledge of music electronics. HOG'S FOOT Layout.JPG HOG'S FOOT PCB co...
by Manfred
11 Jun 2020, 00:06
Forum: Boutique Stompboxes dissected...
Topic: Whisper of Screams (Kasha OD Pedal Trace)
Replies: 7
Views: 667

Re: Whisper of Screams (Kasha OD Pedal Trace)

Have you tried to replace the 1m resistor in front of the second transistor with a pot? Maybe this could replace the "whisper" mode? The resistor network of the three resistors connected to the gate of Q2 together with the input capacity (Cin = Cgs + Cgd * stage gain) form a low pass filter with a ...
by Manfred
10 Jun 2020, 01:47
Forum: Boutique Stompboxes dissected...
Topic: Whisper of Screams (Kasha OD Pedal Trace)
Replies: 7
Views: 667

Re: Whisper of Screams (Kasha OD Pedal Trace)

I was pleasantly surprised & amused when I discovered the the Drain and Source pins can be swapped without issue.
Some JFETS are indeed symmetrical.
by Manfred
08 Jun 2020, 09:42
Forum: Modern Stompbox Effects (1975 - ...)
Topic: EHX - Hog's Foot / Mole - Bass Booster [schematic]
Replies: 3
Views: 608

Re: EHX - Hog's Foot / Mole - Bass Booster [schematic]

The Hog's F007 Bass Booster still has the old EHX logo.
I bought a Big Muff in 1973 which also had this lettering, unfortunately I sold it decades ago.
Therefore I assume that the Hog's is from the very early seventies.
Who knows when EHX changed from the simple to the squiggly lettering?
by Manfred
07 Jun 2020, 12:11
Forum: Pedal Debugging & Troubleshooting Support
Topic: Anything wrong with this blend control? Not seeing any signal from oscilloscope here
Replies: 5
Views: 184

Re: Anything wrong with this blend control? Not seeing any signal from oscilloscope here

I'm trying to make a modded big muff, one of the mods being a blend control. I'm seeing signal at least into the first stage of the big muff from my oscilloscope, but not at the blend opamp or R35, only at the input end of C21 but not even the other side... Thought I had this figured out but maybe ...
by Manfred
06 Jun 2020, 09:06
Forum: Pedal Debugging & Troubleshooting Support
Topic: Xotic BBpreamo bass no Gain
Replies: 18
Views: 463

Re: Xotic BBpreamo bass no Gain

With an normal multimeter you can also measure AC voltages in the lower frequency range.
The output signal of the guitar generated with low E-string or A-string should work.
Up to which output of the OP-amps you can detect the signal with the audio probe?
by Manfred
04 Jun 2020, 21:29
Forum: Pedal Debugging & Troubleshooting Support
Topic: Xotic BBpreamo bass no Gain
Replies: 18
Views: 463

Re: Xotic BBpreamo bass no Gain

Hi Shiflet

The error is difficult to find without measurement, what measuring equipment do you have?
by Manfred
03 Jun 2020, 22:12
Forum: Modern Stompbox Effects (1975 - ...)
Topic: Hofner - Fuzz (2009, IC-based) [schematic]
Replies: 17
Views: 3148

Re: Hofner - Fuzz (2009, IC-based) [schematic]

The switch is a 3PDT switch and is wired as a true bypass switch with switched LED as well as many modern effect devices.
HoefnerFuzzTrueBypass.JPG