I'm continuing to trace Exar pedals from my collection. This time it's FL-1 Enveloper filter. I have 2 of them, both made in 1993. I traced the one with the worse cosmetical condition because its paint was very fragile. The nicer one is on photos, with the box, warranty card, and instructions.
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The PCB is a small single-sided; I traced it pretty quickly. It has two HEF4069UBP by Philips and one Motorola...

Roll Boost Schematic

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Another Exar from my collection, DS-1 Distortion from the first series. The unit was made and sold in 1993; I have a box! I also looked at the price written on the box 455 000 PLN, which was about 25$ in 1993.

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It was virgin (had secure paint on one screw untouched), so I was the first person who opened it up. Unfortunately, the paint on series 1 and 2 is very fragile, it immediately started to take off.

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PCB looks excellent and is...

Gut shots -

Not the best photos, sorry - cables get in the way. Really needs all the wires to be de-soldered to get a proper look at it.
Input is top-right of the circuit (W1 & W2), then heads down the right-hand-side, across & back up the left-hand-side. Looks like there ground plane on the component side of the board is split to improve input/output separation.
Most of the caps are through-hole.
A lot of SOT-23 transistor pairs C6 and DG . There are a couple of 8 pin ICs in there too. 99M...

My first reversed stompbox

Just gonna leave this here. Photos not mine.

Looking for a schematic for the MXR M-103 Blue Box (the version with the two LM741CN)

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Heres a trace drawing I made of this pedals layout. I'm not adept at drawing the layout in the electronic format like the way schematics are available here but this is the full trace of the pedal with values of the components.

The smd caps were measured in circuit. There are two zener diodes on top left corner, i didnt look up the symbol for it to use here. The battery negative lead connects to ground, forgot to draw that in there. Output Sleeve wire is to be grounded...

I needed an expression pedal and boy, this one is cheap!

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Hi all!

I got this pedal in a trade and I really enjoy it!

It is in fact a copy of the Lovepedal Amp Eleven
(minus some parts)

There is also a deluxe version of this unit, the 'Deluxe preamp'; this pedal has three extra switches installed to control the clipping of the booster and the clipping of the overdrive circuit.

In this Amp Turbo version the PCB has patches for the switches, but no switches are installed
Also the boost function has all the diodes you can switch, but as the switch is...

Hi,

does anyone have a layout for the Boss PW-2 Powerdriver?

It´s a quiet unique and interesting sounding distortion pedal that was only built for a couple of month ( <20.000 units made).
I sold that pedal cause I only use diy effects with a true bypass, but now I found out that I can´t copy the sound of the pw-2 :( ...

schematics:

info:

Where are the kings of the veroboard who bring this little machine back to life? :D

regards, Immo

Hi,

I just got one of these little plastic Boss clones (plastic but sturdy, not behringer-style at all), I wanted to have a look at the circuit.

I can confirm that it is clearly a Boss CE-2 clone, with an mn3101 and an mn3007, and some minor differences :
- Q1 is a C1000, not a 2SC732TM
- R1 comes before C1 (if someone knows if that changes something, I'm interested)
- R36 is a 1k8 and R37 is a 8k2, instead of being two 4k7 like in the original schem. I'm going to try putting in the...

In patent 4627094 of December 2, 1986, Tom Scholz described a guitar compressor.

He also highlighted an issue with the release times of the compressor.

Tom described the ADSR curve of a guitar signal as follows:

On a guitar, the first sound or pulse that comes out can be a huge peak which is almost always much stronger than the signal that follows after a few milliseconds.

Then he described the problem with his earlier versions of the compressor:

The operation has not been found to be...

Great sound! Fuzz

Hi.
A friend lent me this pedal, I wanted to see what it was.
Basically a rat with input buffer and two separate controls for dry and wet volume, and probably an extra output boost too (that I didn't trace).
The most interesting part was the gain/frequency resistor and capacitor (330 ohm and 6µ8, to save you some time) but what took me a really long time is what looks to me as a very elaborate clipping switch and volume control for LED clipping (controlled by the internal trimpot, described by...

Hello

I know this is a Tone Bender circuit, but does anyone know what they are doing to create the impede control? Or what they did for the mids/stock/fat switch?

Thanks
Rob
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I am still trying to get a Rockman X100 I built a year or so ago fully working. I am getting too much compression despite adding a potentiometer to try to control it better. I have been looking at rockman.fr which is a mine of information on all the Rockman products. I think my problem relates to the 2n4339 FET transistor which needs to be properly biased. On the schematic, there are two resistors with guide values of 6.8 M and 5.1 M with a note that the specific values are factory selected to...