Hello all.

I recent spent a Whopping $10 for a UT-300 Ultra Tremolo.

Great sounding tremolo, but does anyone know how to modify it to make the LED flash at the tremolo rate?

Thanks

I traced Exar FL-1 Flanger from my collection 🎉. The unit should have been made in 1989 or later due to the dates on the pots (09-89). I even have the box 😅.

PXL_20221219_211836112.jpg

This trace was quite challenging due to amount of components on the small single-sided PCB.

PXL_20221217_195623135.jpg
PXL_20221217_191615264.jpg

As I started, I immediately realized that it was based on... Boss BF-2. But when I went to the LFO section, it was completely different. So it is definitely...

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.
PXL_20221206_135104506.jpg
PXL_20221206_135123013.jpg
PXL_20221206_135143814.jpg

The PCB is a small single-sided; I traced it pretty quickly. It has two HEF4069UBP by Philips and one Motorola...

If a moderator wants to delete this thread for not being stompbox related then I totally understand.
Could you please let me know your specific reasons though?
Why am I posting this here?
[] I don't think that posting this to a computer-related forum would succeed - business interests would prevent it from seeing the light of day.
[] This forum supports the free exchange of information AFAIK.
[] It might benefit some forum members that use Windows Media Player.
[] Tenuous link - When you listen...

Hi all,

I picked up a faulty EBS Octabass pedal. It works, but when you are not playing, there are constant blips/bops. Essentially, if you even touch a string, you get some signal being generated. Sounds as if the issue I have is very similar to the one described in

I've done a fair amount of reading, and recall somewhere that it could be a pull down resistor (which seems logical to me). Is there an easy way to find which resistor it is from a schematic (the schematic is on the forum)?...

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

M-audio - EXP pedal.JPG

EDIT: I found that I did already have a cable but I'd still like to know if the connector is something I can buy so I can make a 2nd cable.
Condor_Cable.jpg

I'm already searching doggedly, but I can't find a circuit diagram for this device. Maybe someone has such a circuit?

Le HAUT-PARLEUR 18 Avril 1968 Générateur de distorsion.pdf

Le HAUT-PARLEUR 18 Avril 1968 Générateur de distorsion.jpg

PDF: RP219_01-1966_A_REFAIRE Reverberation modulation.pdf

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01 RP219_01-1966_A_REFAIRE Reverberation modulation.jpg 02 RP219_01-1966_A_REFAIRE Reverberation modulation.jpg 03 RP219_01-1966_A_REFAIRE Reverberation modulation.jpg 04 RP219_01-1966_A_REFAIRE Reverberation modulation.jpg 05 RP219_01-1966_A_REFAIRE Reverberation modulation.jpg 06 RP219_01-1966_A_REFAIRE Reverberation modulation.jpg

Radio-TV-Experimenter-1967-12-01 Universal Reverb.pdf

01 Radio-TV-Experimenter-1967-12-01 Universal Reverb.jpg 02 Radio-TV-Experimenter-1967-12-01 Universal Reverb.jpg 03 Radio-TV-Experimenter-1967-12-01 Universal Reverb.jpg 04 Radio-TV-Experimenter-1967-12-01 Universal Reverb.jpg 05 Radio-TV-Experimenter-1967-12-01 Universal Reverb.jpg

PDF Poptronics-1968-01 Meyer Reverb Adapter.pdf

01 Poptronics-1968-01 Meyer Reverb Adapter.jpg 02 Poptronics-1968-01 Meyer Reverb Adapter.jpg 03 Poptronics-1968-01 Meyer Reverb Adapter.jpg 04 Poptronics-1968-01 Meyer Reverb Adapter.jpg

PDF: RC-1963-03 Simple Echo Chamber.pdf

01 RC-1963-03 Simple Echo Chamber.jpg 02 RC-1963-03 Simple Echo Chamber.jpg 03 RC-1963-03 Simple Echo Chamber.jpg

PDF: Radio-Electronics-1962-01 Reverberation.pdf

01 Radio-Electronics-1962-01 Reverberation.jpg 02 Radio-Electronics-1962-01 Reverberation.jpg 03 Radio-Electronics-1962-01 Reverberation.jpg

Full article in PDF: Pop-1960-12 Controlled Reverberation.pdf

Pop-1960-12 Controlled Reverberation schematic.jpg

PDF: Electronics-World-1966-10 Simplified Tremolo.pdf

Electronics World Vibrato.jpg

PDF: Radio-Electronics-1951-02-OCR-Page-0082.pdf

Radio-Electronics-1951-02-OCR-Page-0082.jpg

PDF: Radio-Electronics-1966-11 Thunderbox Booster.pdf

Radio-Electronics-1966-11 Thunderbox Booster 01.jpg Radio-Electronics-1966-11 Thunderbox Booster 02.jpg

PDF: Hobby-Electronics-1982-12-S-OCR Phase Four.pdf

01 Hobby-Electronics-1982-12-S-OCR Phase Four.jpg 02 Hobby-Electronics-1982-12-S-OCR Phase Four.jpg 03 Hobby-Electronics-1982-12-S-OCR Phase Four.jpg 04 Hobby-Electronics-1982-12-S-OCR Phase Four.jpg 05 Hobby-Electronics-1982-12-S-OCR Phase Four.jpg

Edit: in the drawn PCB view the polarity of the unidentified protection diode was upside down, now it is corrected.
I replace it with a 1N4001 diode
I bought this defective Amiko NSG-2 noise gate pedal, it is identical in design to the PSK NSG-2 pedal.
Since I could not find a schematic, I drew it out by tracing the circuit board.
This pedal is a BOSS NF-1 noise gate clone.
Differences are:
External power supply through a DC adapter instead of a DC adapter.
C=47n instead of C=100n and R=470k...

Hi guys. I am trying to replace an Alpha 9mm D-shaft PCB mount C500k pot on a pedal, anyone knows where can I order one? I have been googling for two days with no luck :(

Similar to this design but D-shaft version:

Thanks for the lead in advance.

Hi!

I just got one in, and as being a fan of these CMOS pedals, I needed to trace it!

For pics just take a look at my instagram; User: bernardduur

Hot Tubes Nano.JPG

PDF - Radio-TV-Experimenter-1966-06-07 Audio Compressor.pdf

Radio-TV-Experimenter-1966-06-07 Audio Compressor 1.jpg Radio-TV-Experimenter-1966-06-07 Audio Compressor 2.jpg Radio-TV-Experimenter-1966-06-07 Audio Compressor 3.jpg Radio-TV-Experimenter-1966-06-07 Audio Compressor 4.jpg Radio-TV-Experimenter-1966-06-07 Audio Compressor 5.jpg Radio-TV-Experimenter-1966-06-07 Audio Compressor 7.jpg

Does anyone has pics of the pcb for this one (blue pcb)?

I found only these pics

I'd like to check what they changed from this one that has green pcb

Thanks

I'm experimenting with the EHX Small clone, but don't really understand why they put the transistor at the start of the circuit, why not just have a bit of filtering instead of the extra stuff.

Just curious.

I should add, I'm using two LM13700 OTA Ics instead of multiple CA3094s.