Bruce, Thanks for the ideas. The HSMS-2822 looks like it could serve in the detector role, while a pair of HSMP-3822's might work for clamping--low capacitance, matched pair in series, and in stock at Mouser. The 3822 is actually a pair of PIN switch diodes, but couldn't it function as a clamper? The 482x series looks better for clamping, but isn't available in a series-pair configuration. There are other possibilities, but not many in stock, and I couldn't find any suitable ring diode packages.
Bob WA7ZRX -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Bruce Griffiths Sent: Monday, March 31, 2008 6:37 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Adding prescaler to HP 5334B Bruce Griffiths wrote: ... > 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 > Quad CR303 acts as a clamp, Quad CR302 acts as a detector with temperature compensation. Only 2 diodes in CR302 are used so CR302 can be replaced by a matched pair. Try using low barrier microwave specified schottky diodes with lower capacitance than a 1N5711. Bruce _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.