[vtech]

Impossible to determine the cause without actually opening up & testing the unit; in general there may be a number of things from power supply/HV/filter capacitance/Tubes/txformers...etc

[DJ4SU]

Hi,
I am even not sure if I am posting this in the right forum. Anyway, help would be very much appreciated.
Im using ham radio gear, among others a linear power amplifier from Yaesu Model FL 2277 in a remote part of Denmark with no competent electronic repair facilities near by. During an operating cycle I saw a flash and heard a noice from the amplifier and immediately the high voltage indicator of the final tubes`plate voltage went to zero. Checking the main fuse it was ok, already also indicated by a still illuminated power-on indicator. Before I am going to open the amplifier I would like to get some expert opinion what probably has been happened ( I assume a shortened amplifier tube caused by overloading and consequent heat development). If there is likely more damage than a blown internal fuse in the high voltage circuit I will just put the amplifier aside and wait for the next jouney to Germany. I should mention, that I don*t even have a circuit diagram with me. Thanks Peter