Ok, then did you swap the output tubes between channels, like with the small tubes?
The HF noise could be a bad tube, or oscillation from some other cause.
Try lightly tapping on each tube with an eraser, etc. to see if the noise is affected.
It could be a microphonic tube. Have you tried cleaning the sockets and pins, and RCA sockets?
The hum is likely a different problem, best left until after the HF noise is fixed.
Can you post a schematic?
The HF noise could be a bad tube, or oscillation from some other cause.
Try lightly tapping on each tube with an eraser, etc. to see if the noise is affected.
It could be a microphonic tube. Have you tried cleaning the sockets and pins, and RCA sockets?
The hum is likely a different problem, best left until after the HF noise is fixed.
Can you post a schematic?
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It's possible, especially if this is a recent problem. However, it could also be a failing component,
like a bad electrolytic capacitor. Since the noise is only in one channel, that rules out capacitors
that are shared between channels.
Is the hum still there when you insert shorting plugs into both RCA input sockets?
like a bad electrolytic capacitor. Since the noise is only in one channel, that rules out capacitors
that are shared between channels.
Is the hum still there when you insert shorting plugs into both RCA input sockets?
Hum in Left Channel of TU-8600
Hello,
I just started having an issue with my TU-8600. A low level hum in the left channel has appeared. It has been a wonderful sounding amp since I built the kit a few years ago and I have really enjoyed it. The hum just appeared in the left channel. I moved tubes from Left to Right channel and the hum remains on the left channel. It is there whether there is anything plugged into the RCA jacks or not. I have to suspect a component at this point. If someone has any ideas as to where to start I would be very grateful.
Thanks a bunch.
Hello,
I just started having an issue with my TU-8600. A low level hum in the left channel has appeared. It has been a wonderful sounding amp since I built the kit a few years ago and I have really enjoyed it. The hum just appeared in the left channel. I moved tubes from Left to Right channel and the hum remains on the left channel. It is there whether there is anything plugged into the RCA jacks or not. I have to suspect a component at this point. If someone has any ideas as to where to start I would be very grateful.
Thanks a bunch.