Search found 1006 matches

by Manfred
Today, 10:36
Forum: DIY Stompbox designs
Topic: Guitar Distortion Pedal, Popular Electronics, September 1999
Replies: 4
Views: 406

Re: Guitar Distortion Pedal, Popular Electronics, September 1999

I created this PCB clone and inserted the components according to the schematic. GuitarDistortionPedalLayout_1.JPG GuitarDistortionPedalLayout_3.JPG GuitarDistortionPedalLayout_2.JPG Ready to Print PDF-files: GuitarDistortionPedalPCB_SolderSide.pdf GuitarDistortionPedalPCB_ComponentSide.pdf SprintLa...
by Manfred
02 Sep 2020, 21:57
Forum: Pedal Debugging & Troubleshooting Support
Topic: germanium FF noise
Replies: 6
Views: 281

Re: germanium FF noise

Connect a fixed resistor e.g. 470 Kiloohms or a potentiometer e.g. 1 Megaohm to the input of the FF and see if the noise behaves the same as with the plugged in guitar.
by Manfred
02 Sep 2020, 15:51
Forum: Pedal Debugging & Troubleshooting Support
Topic: germanium FF noise
Replies: 6
Views: 281

Re: germanium FF noise

Did you install transistors with selected gain?
by Manfred
01 Sep 2020, 13:54
Forum: Pedal Debugging & Troubleshooting Support
Topic: germanium FF noise
Replies: 6
Views: 281

Re: germanium FF noise

but guitar volume at zero through the pedal is dead silent..
The internal noise voltage source of the transistor is probably short-circuited to ground.
Can you find a noise minimum in the control range of the guitar's volume control?
by Manfred
31 Aug 2020, 15:57
Forum: DIY Stompbox designs
Topic: Royal Albert Hall schematic
Replies: 9
Views: 663

Re: Royal Albert Hall schematic

I have traced the following strip layout and compared the found circuit with the schematic from the post above. The circuits are identical except for a tiny deviation. In the strip layout a 1 Megohm resistor has been added between input and ground. RAH Rev2.jpg the Tone Stack is this one from the fo...
by Manfred
29 Aug 2020, 22:23
Forum: Vintage Stompbox Corner ( ... - 1975)
Topic: Zenta - Exciter [Schematic]
Replies: 3
Views: 929

Re: Zenta - Exciter [Schematic]

What are the dimensions of the board?
by Manfred
29 Aug 2020, 22:18
Forum: Pedal Debugging & Troubleshooting Support
Topic: Best practises for diagnosing volume loss?
Replies: 5
Views: 472

Re: Best practises for diagnosing volume loss?

What measuring equipment do you have at your disposal,
e.g. signal generator, oscilloscope?
After a look in the schematic I would say that the dry signal path has about unity gain.
How much of the input signal comes out at the output.
by Manfred
29 Aug 2020, 03:48
Forum: Modern Stompbox Effects (1975 - ...)
Topic: Reagun - Overdrive [schematic]
Replies: 4
Views: 1244

Re: Reagun - Overdrive [schematic]

George Giblet found a bug in the Reagun Distortion schematic that has the same switching circuit as the Overdrive.
It is also the same error in the schematic.
Thanks again George.
Here is the corrected circuit:
ReagunOverdriveSchematicCorrected.JPG
by Manfred
29 Aug 2020, 03:31
Forum: Modern Stompbox Effects (1975 - ...)
Topic: REAGUN DISTORTION traced
Replies: 4
Views: 612

Re: REAGUN DISTORTION traced

Hi George,

Thanks for looking closely you are right.
ReagunDistrotionSchematicCorrected_2.JPG
by Manfred
28 Aug 2020, 16:00
Forum: Modern Stompbox Effects (1975 - ...)
Topic: REAGUN DISTORTION traced
Replies: 4
Views: 612

Re: REAGUN DISTORTION traced

During the repair I found an error in the schematic, the resistance between terminal 5 of the OP-amp and the 4.5 volt point has a value of 470 Kiloohm and not 22 Kiloohm.
ReagunDistrotionSchematicCorrected.JPG
by Manfred
27 Aug 2020, 16:22
Forum: Boutique Stompboxes dissected...
Topic: Seymour Duncan - 805 overdrive
Replies: 24
Views: 5974

Re: Seymour Duncan - 805 overdrive

I guess I never got problem with shared hole and under part jumpers, especially when I use the thinner lead cut from the old resistors by Tayda.
No worries this is not a common problem but my personal problem. :)
by Manfred
26 Aug 2020, 10:45
Forum: Boutique Stompboxes dissected...
Topic: Seymour Duncan - 805 overdrive
Replies: 24
Views: 5974

Re: Seymour Duncan - 805 overdrive

Hi Ichabod_Crane checked your vero-layout and found the errors I marked in the image. To trace them I made a copy of your layout with the Lochmaster 4.0 layout program. This program provides a trace function which highlights the selected connections in color. I have moved the jumpers that used the c...
by Manfred
19 Aug 2020, 03:38
Forum: Amplifiers
Topic: MESIA ZOOM Tubeamp Schematic [schematic]
Replies: 4
Views: 540

Re: MESIA ZOOM Tubeamp Schematic [schematic]

Great, now also the transformer voltages are known. :thumbsup
by Manfred
16 Aug 2020, 19:20
Forum: Amplifiers
Topic: ROZZ RGA-6TB/10TB Schematic
Replies: 0
Views: 385

ROZZ RGA-6TB/10TB Schematic

I have found these operating instructions for the ROZZ RGA 6TB/10TB in my documents.
This was a combo amp that a friend of mine had in his music shop in the early 1980s.
ROZZ RGA-6TB-10TB Manual.jpg
ROZZ RGA-6TB-10TB Schematic.jpg
by Manfred
13 Aug 2020, 14:54
Forum: Amplifiers
Topic: MESIA ZOOM Tubeamp Schematic [schematic]
Replies: 4
Views: 540

MESIA ZOOM Tubeamp Schematic [schematic]

I had bought this amplifier in the 60 watt version in 1983 defective, the transformer was burned out. I have repaired it in the 1990 years and sold it. Now i have redrawn the very blurred original schematics on a request. Because the transformer was defective I could not measure the transformer volt...
by Manfred
04 Aug 2020, 20:27
Forum: Pedal Debugging & Troubleshooting Support
Topic: DMB Lexi pedal, gated fuzz!?!?!
Replies: 63
Views: 3228

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

Erok wrote in a previous post: DMB said they swapped out the old board for this one, then sent me the pedal back as "working""like new". I asked them to please look at the pedal again, DMB promptly went out of business. That's why there is not a schematic of a working schematic. I had found a DMP Le...
by Manfred
04 Aug 2020, 12:56
Forum: Pedal Debugging & Troubleshooting Support
Topic: DMB Lexi pedal, gated fuzz!?!?!
Replies: 63
Views: 3228

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

So, in the end that is really that the correct schematic? I tried to emulate it with the software, but I got low signal and an important cut of bass and very large treble roll off. The trimmer doesn't help much. Should it carry 4.5v at the J201 drain? According to Erok, this is in fact the traced o...
by Manfred
27 Jul 2020, 10:10
Forum: Pedal Debugging & Troubleshooting Support
Topic: DMB Lexi pedal, gated fuzz!?!?!
Replies: 63
Views: 3228

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

Gain pot connections look odd - output should be from lug 2 rather than 3?
Thanks, you are right I made a drawing mistake.
DMB_Lexi_SchematicCorrected.JPG
by Manfred
26 Jul 2020, 21:00
Forum: Pedal Debugging & Troubleshooting Support
Topic: DMB Lexi pedal, gated fuzz!?!?!
Replies: 63
Views: 3228

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

Finally, the redrawing of the traced schematic of the original board.
DMB_Lexi_Schematic.JPG
by Manfred
24 Jul 2020, 22:20
Forum: Pedal Debugging & Troubleshooting Support
Topic: MT-2 Metal Zone Oscillating
Replies: 4
Views: 235

Re: MT-2 Metal Zone Oscillating

In the case of a breadboard assembly, unwanted couplings can be caused by the connecting wires.
Take a plastic or wooden stick and move the wires and see if the oscillation changes or breaks off.
I assume that you have checked the circuitry.