Hey, guys. I've recently built a RC Booster based on the smallest foot-print shown here in the forum (
link).
The only difference from the schematics is the Gain pot, which I used a B500K, since I don't have the B250K available atm.
The problem is while the controls are at noon I'm hearing lower output volume than the pedal switched off. It is also lowering the high frequency, turning it darker than it should and when I max out the treble pot I can't get much more highs than my original amp sound.
When I turn up the level, than I can get good boost, but I need to lower the gain too much to have a real clean boost, than I lose a lot of volume again making it lower than my amp alone.
Basically, to have a real clean transparent low level boost, I need the Volume pot at 2-3 o clock, lower the gain to 9-10 o clock, lower the bass to like 10-11 and increase the highs to 2-3 o clock.
Based on the youtube reviews about the original pedal, it should give a bit of boost with controls at noon and very subtle frequency modifications.
I checked the resistor values (found a bad solder joint on one resistor), looked for other faulty solder joints, unwanted bridges, but nothing else found and scratching between traces did nothing as well.
The IC and Transistors voltages are as follows (Volts):
Texas Instruments RC4558P:
1: 4.56
2: 4.6
3: 4.6
4: 0
5: 4.6
6: 4.6
7: 4.63
8: 9.3
Q1 - 2N5088:
C: 9.3
B: 2.44
E: 2.07
Q2 - 2N5088:
C: 9.3
B: 4.05
E: 3.73
What about those voltages? Are they correct and expected for this pedal?
Should the gain pot be really a B250K to make the pedal work as intended?
Is the volume pot on this pedal really log/audio type? I've seen someone saying it is linear in a forum.
I'll attach some pictures later because I had to stop tinkering with the project to do other stuff.
Also, I'm gonna re-solder the high pot legs and wire to the board and measure the clipping diodes forward voltage.
Thank you all for the support.
Cheers!
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