New advances.
I lifted (cut) from T13.5V the choque L05 feeding predriver, and TX13.5V intensity went down to 250mA. In this line only transistor Q01 or capacitor C18 can produce the short. I guess it is the capacitor.
At the same time I noticed 3,3V zener D01 has only 2,9V. It has capacitor C13 in parallel. Therefore voltage Bias for predriver is low. In short whenever I look close to a tantalum I see they are not fully OK. I dont pretend to repair it "as new" but at least to clean possible dangers upwards as a damaged tantalum mean a short. I guess I will not touch the ones in very low voltage lines, 0.7V and similar. But I think I have to take care of those directly on the 13.5V lines from the PS. Specially TX13.5V because it passes a relay in RF unit that can be damaged. Luckly the PS intensity protection worked (I hope) when I measured only 3V in the relay output.
I dont have the right tools neither the eyes for a good repair, but I hope I can make it functional.
I have found other tantalum in IF unit, but I guess they are not in essential places, NB f.i. So I dont know if I will change them. A pitty because 30 years ago I installed 3 IF filters, and then if would have been easy to change tantalums in that board. Now 30 years later, I am 30 years older...
73 EA1FC
