Recent content by temol

D5... ;) Breadboarding now... from Zeppelin to ACDC.

Mine is "working". I still can't bring myself to analyze the noise issue - quite strong hum in the low frequency range. I have two suspects so far - tube heaters or transformer. Oh, and I ordered the PCBs myself.

IDSS or Vp? 0.9mA for the MMBFJ201 seems to be really high value. -0.9V - ok (but in the higher range).

Rev 0.2 in 0805

The 1N4007 diodes should have different numbering. They are now D3 and D4, duplicating the LEDs.

@djathey, @keyth72 - big thanks! :)

@keyth72 - I could not find any info about function of the dipswitch. thanks!

Second interview with DG.

A friend sent me an EBS Dynaverb pedal for inspection. It's a digital (probably DSP) reverb. It worked flawlessly for a long time, until suddenly some digital noise appeared. I looked inside – there were no signs of damaged components (the capacitors looked fine), and no signs of water damage...

"From Monday, 25 August 2025, no shipments to the USA due to changes in customs regulations". Quote from German webstore (synth-parts). I wonder if this is an exception or will soon become a more common sight.

It is good practice to separate IN and OUT. Maybe not that much as on my example, but in-led-gnd-out should be enough. Why such thin tracks? Why ground pour only on the bottom?

Buy smd version of the J201 - MMBFJ201. they are cheaper and more reliable. You don't even need daughterboards for them. Chop Shop has solder pads for smd transistors. Check PPCB (3$ for 5 pieces), Mouser...

In my basement :) . 100% DIY.

How do you plan to power the opamps? You either need a symmetrical power supply or a reference voltage from a voltage divider. GND... It depends on whether you have a symmetrical power supply or a reference voltage (Vr) But... Take a proven hi-gain circuit with opamps, add a few things...

Can you show an example schematic with such a tone stack?