Hey there everyone! Been trouble shooting my harbinger build on and off for a week or two but now I feel like I've hit a wall! So the issue I am seeing is that the rate LED on the harbinger flashes properly and responds as it should to adjustments of the speed pot however the lamp itself only glows steadily; no pulsing at all. I've double checked my speed pot wiring and spent most of my time focusing on the LFO section of the circuit. I haven't been able to find/see any drastic voltage drops on any of the components in the section so I am assuming everything is flowing correctly? Here are the reading i took off the LFO section:
Q11
C 15.79
B Variable between 6-8
E Variable between 8-9
Q12
C 15.78
B Variable between 8-9
E Variable between 6-9
Q13
C 12.2
B 3.0
E 2.3
Now I have to mention that I do have a mix of carbon and metal resistors in the R41-R46 row because I had some left over
in my parts bin but they're rated the same so I assume that's ok? Any guidance would be greatly appreciated and please let me know if you need anymore information.
THANK YOU IN ADVANCE!!!!
Hi,
Can you post a pic of the board?
Q13 is the one to socket and try a different transistor if you have some spares.
Thanks
Ernie
https://www.geargasstore.com
Thanks for the reply Ernie! An interesting (and frustrating) development has occurred though as of yesterday. I went down to the bench last night to take pictures for you and found that I accidentally left the pedal plugged in. Low and behold the lamp was now flashing away! I'm happy it mysteriously started working for some reason but also kind of annoyed because I really wanted to figure out what was going wrong with it!!! If anything changes I'll send an update.
Hi,
Excellent! That's great to hear!!!
Thanks
Ernie
https://www.geargasstore.com
Damn those are frustrating troubleshoots though. You don't want to touch it cuz it works, but you want to figure out what it was so it doesn't happen again...
Quote from: thrillhouse on March 02, 2018, 03:49:40 PM
Thanks for the reply Ernie! An interesting (and frustrating) development has occurred though as of yesterday. I went down to the bench last night to take pictures for you and found that I accidentally left the pedal plugged in. Low and behold the lamp was now flashing away! I'm happy it mysteriously started working for some reason but also kind of annoyed because I really wanted to figure out what was going wrong with it!!! If anything changes I'll send an update.
I hate it when gremlins come in and fix stuff without telling you.