Info

Jim Kyle K5JKX/6

f Ank of the best buys arounc on the surplus ^-'market—when you can find it—is the BO 779 receiver. In its civilian dress as the Ham-marlund Super-Pro, the rig is well-known and justly famous.

The old Pro, however, has one design feature which is at the same time an advantage and a disadvantage. The power supply is on a separate chassis from the rest of the receiver.

Most of the time, this is a great help, The receiver runs cooler, there is less trouble with induced hum« and weight of each unit is somewhat lessened.

The only time it proves to be a severe disadvantage is when you find one in your surplus supply house—without power supply.

"So what," do I hear you ask? "What's so tricky about building a power supply?"

Really, it's not so hard. But the Super-Pro power supply, actually, is not one but tw5 separate supplies. One furnishes 385 volts at 100 ma, 310 volts at 80 ma, and 270 volts at 50 ma. Tlui other furnishes negative 50 volts for fixed bias. And duplication of the original

0 0

Post a comment