Egnater Tweaker 112 Combo No sound.

Egnater Tweaker 112 combo won't make sound through normal channel. It will work if I run a pedal through the effect loop return. Slow blow fuse does not blow. All the pre amp tubes have been replaced. Still not working. Any suggestions?

Hi Mark
By the way, is it a Tweaker 15 combo or Tweaker 40 combo ?
If Tweaker 40, is the problem that it works on Channel 2 (red LED) but not in Channel 1 (green LED).
Then I guess that it is a relay problem. One of the relays that switch the signal between channel 1 and 2 does not work properly.
/Kalle

It is a Tweaker 15. I bought it used and it worked really well for a while. I talked to some one at Egnater and he said if it would play through the effects loop that bypasses the preamp. I changed all three 12L7 preamp tubes no change.

I plan on calling Egnater again tomorrow. I was just hoping someone might help over the weekend.

Hi Mark
Having sound by connecting the guitar (via pedal) to Loop Return shows that 6V6 tubes , V3(12AX7,Phase Inverter) and at least half V2 ( 12AX7 loop reciever) works.
And if one half of V2 works, then the other half of V2 probably also works.
Have you tested to connect a guitar cable between Loop send & return.
(It could be simple fault in the send/return connectors)
But if that doesnt work and you have changed all 12AX7 tubes, then I would guess that one of transistors G2(2N5485) and G1(IRF820) or both are broken.
These two transistor are connected in a Cascode configuration that is the first signal gain stage in the Pre-Amp.
/Kalle

I had this same issue with my Tweaker 40. Channel 1 worked but channel 2 did not. I replaced pre amp tubes, that did not help and the preamp tube still sounded microphonic. I then started doing some research on diagnosing tube amps and I found out that you can find bad capacitors by tapping on the with a pencil the way you test for bad tubes. I took the amp apart and started tapping on capacitors with a wooden pencil around the pre amp tube and then wham, found it. It was c23 on my board but I do not know what it is on yours. I paid 1.52 for the replacement capacitor that I got from my local electronic store and soldered it in. That fixed the problem. It is an easy cheep fix but I do not recommend doing it yourself if you have no experience in fixing amps. There is high voltage and it is extremely dangerous if you do not know what you are doing.