I've just built my first pedal - Aion FX Radian Germanium Boost. But it's not working.
1) When biasing the transistor, it will only go as high as -3.53v rather than -7v.
2) When plugged in with either battery or power supply, sound goes through when pedal is bypassed, but there is no sound when the pedal is activated.
3) I checked the charge pump which seemed to be OK. It measured -9.13v at the lower right pin of the IC
Any help would be greatly appreciated.
(https://i.postimg.cc/xcmPgdXc/20231219-155224.jpg) (https://postimg.cc/xcmPgdXc)
(https://i.postimg.cc/34WXGrMr/20231219-174843.jpg) (https://postimg.cc/34WXGrMr)
(https://i.postimg.cc/dhvGBjMx/20231219-174811.jpg) (https://postimg.cc/dhvGBjMx)
Hi & Welcome.. :icon_wink:
Could you plz verify Q1 BIAS trimmer proper value..??
Also, could we see transistor all 3 pin voltages..??
So...
Upon measuring all transistor pin voltages, the issue was immediately apparent. I had soldered the transistor in the wrong orientation. A 2 minute desolder/resolder, and I was able to bias the transistor to -7v.
The result...
An astonishingly great pedal which exceeded my expectations. It's quiet (no hum to speak of) and boosts the sound exactly to my liking, exquisitely replicating a Rangemaster.
I'm so happy with this pedal - and am looking forard to buying more kits from Aionfx.
It's great to know there's support from this community if I get into strife again!
Russian transistors, you have to always look up the pinout, well most any transistors you have to look up the pinout, unless you are familiar with them. There are also some, 2SC458, different years had different pinouts.