Thor Problem

[ranchak]

I just finished my build on the Thor. I adjusted Q1 and Q2 to 6.4v and 4.5v. With an audio probe I found that I was not getting much audio through C2. I replaced this cap with one from a different manufacturer and that corrected the problem. I then found that I have little to barely audible signal through C3 and C4. I used tantalum caps for these, I do not have anything to replace them with. Any thoughts on where my problem lies.... I did notice that my original cap that I used for C2 was physically smaller than it's replacement. I didn't think that physical size was a factor in capacitors. The tantalum caps that I am using are really small. Any help would be appreciated.

[Barcode80]

do you have any electros around? they don't have to be tants. plus, you won't always hear a lot of signal at every cap, just depends on the circuit.

[ranchak]

These caps are small, 470pf. I can hear the boost on Q1, but I'm not getting any audio to/through Q2.

[B Tremblay]

How did you build it?  PCB, vero, or perf?  Which layout did you use?  Are you sure that the offboard wiring of the Gain pot and Bright switch is correct?

I don't have much experience with tantalum caps, but I've never read of them being available in 470pF.  Do they measure as that on your meter?

[Barcode80]

i agree, i've never heard of tants that small, but if it is, you might want to check the orientation of them. Tantalums are polarized like electrolytics, and putting them in the wrong direction will usually kill signal PDQ.

[ranchak]

My build is PCB from the ROG website. I did not check orientation of the caps, that sure could be the problem. I am pretty sure that the off board wiring is correct. I will check the caps.

[ranchak]

I guess I do not have tantalum caps, these must be axial polyester caps. Would the signal still travel through R4?