It is a classic designing of final amplifier 35 W, with two EL34 in push-pull, from the Siemens and Halske.
The amplifier it worked from 1954 until 1989, whenever it came also out except operation, with mean of operation 15 hours per day. It did not present particular damage beyond the replacement of tubes, resistances and capacitors, result of natural deterioration. A essential change became with the replacement of restoring provision from tube, with diodes. The alone problem that will exist, for those who they try his manufacture, will be the transformer of expense, (it is in effect for all the tube manufactures), one and code that exists it will help. It can be replaced with a classic transformer of expense suitable for EL34. In his manufacture it needs (it is in effect for all the corresponding circuits), enough experience and attention in high voltage, danger of Electric Shock.
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