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Hey all,
I don't usually post here with hat in hand although I presently have a particularly nasty repair situation on the bench. It's a H&K Statesman with EL84's. The initial problem was a buzz when the amp is on the clean channel.
I was able to trace the problem to the OD section. Unfortunately, another problem has surfaced which is causing much frustration. There's a FET on the grid of the first gain tube where the switching for the channels goes in. It's leaking and now causing the clean channel to shut off. It's function seems to be either for setting the bias to the grid but far more likely, it's a clamping FET. Either way it's connected to -33V, ground and the input grid of the tube. Of course, the original FET is no longer produced. I tried a replacement FET but to no avail.
I contacted Yorkville as they're the distributor, but they were no help at all.
Does anyone have a source, or the schematic for this?
Many thanks,
Richard
I don't usually post here with hat in hand although I presently have a particularly nasty repair situation on the bench. It's a H&K Statesman with EL84's. The initial problem was a buzz when the amp is on the clean channel.
I was able to trace the problem to the OD section. Unfortunately, another problem has surfaced which is causing much frustration. There's a FET on the grid of the first gain tube where the switching for the channels goes in. It's leaking and now causing the clean channel to shut off. It's function seems to be either for setting the bias to the grid but far more likely, it's a clamping FET. Either way it's connected to -33V, ground and the input grid of the tube. Of course, the original FET is no longer produced. I tried a replacement FET but to no avail.
I contacted Yorkville as they're the distributor, but they were no help at all.
Does anyone have a source, or the schematic for this?
Many thanks,
Richard