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200W DATV power amplifier- 50V 20A power supply

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200W DATV power amplifier- 50V 20A power supply Introduction I am builder a DATV power amplifier, about 200W maximum. The power supply is unusually powerful as the amplifiers are only bout 25 per cent efficient. Commissioning such a power supply is not simple. DATV power amplifier I discovered through one of the Yahoo groups that it was possible to buy UHF DVB-T pallet amplifiers, broad band from 470 MHz to 900 MHz. I bought one through the Italian eBay for 400 Euro. It has a pair of BLF888A  LDMOS transistors. The pallet is a pair of amplifiers with a splitter and combiner to allow single in and out. The BLF888A are each a match pair of transistors in push-pull. Power supply The power requirements are about 48V at 20A as the amplifiers are only about 25 percent with the ultra linear DVB-T. I remembered that a lot of telecommunications equipment use 48V, so had a look on eBay. I managed to buy a new  ELTEK Flatpack2 2000W 48V HE Power Supply for $150. These are state of