Robert Berg wrote: > Having seen it discussed, I was wondering whether anyone has actually added > the Schottky diodes and prescaler chip to a 5334B to provide a C-channel > input. The matched Schottky quads (5082-2831) are no longer available, and > even the recommended replacements (5082-2303) seem scarce. Was thinking of > trying 1N5711s, which can be obtained as matched sets, although probably not > on my budget. How critical is the need to use matched sets? The NEC > UPB1507GV-ACT-ND looks promising for the prescaler, if the small form factor > isn't too minute to handle. > > Bob > WA7ZRX > Not particularly critical as they are only used as clamps to limit the input signal to the 30dB gain preamplifier. You may be able to use a single pair instead, albeit with a lower input damage level. Using a quad allows the clamp current to be shared between a pair of diodes, however some matching is required to ensure effective current sharing. Too much diode shunt capacitance will limit the bandwidth.
Bruce _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
