Hiwatt DR103 Copy Brilliant Channel is Dead

[ThreeChordWonder]

The input volume does nothing. Virtually no sound, if any at all out of the Brilliant channel but the Normal channel works just fine.

Apart from the obvious, is there anything I should check?

I'm assuming that since the Normal channel works fine, and the two channels get combined before the second preamp tube, the fault is upstream of that point, right?

Thanks in advance.

[ThreeChordWonder]

Here's the circuit.

I checked all the voltages at V1 and they're fine, the input leads all read 68k ohms and the connections are fine.

Custom_100_SCH1024_1.jpg

[GAStan]

I'm assuming that since the Normal channel works fine, and the two channels get combined before the second preamp tube, the fault is upstream of that point, right?

Correct.

Have you tried a different tube in V1?

You are on the right track, problem is somewhere around V1A.

Has this channel ever worked or is this a new build?

In short check everything from the input jacks to, and including, the brilliant channel volume pot.

[ThreeChordWonder]

It's about a year old Mojotone kit I built myself.

I've been going though it all day, and finally traced it to a duff master volume pot. No idea how that happened, but "stuff" does happen.

Now working fine.

Thanks everyone.

[GAStan]

Glad you found the problem. My first build was a Mojotone 1 Watt Kit, great kit!

[ThreeChordWonder]

Sorry, not the "Master" volume pot, but the Brilliant Channel pot.

[gldtp99]

OK, that makes sense --- it's just the Channel vol pot, not the MV pot