[time-nuts] Adding prescaler to HP 5334B
brooke at pacific.net
Tue Apr 1 16:36:48 EDT 2008
One way to do that is pair up a long lifetime PIN and a schottky of polarities
such that the Schottky current forward biases the PIN. DC block the input and
output. I made microwave limiters this way many decades ago.
Re: Schottky Diodes
There are two flavors. A pure Schottky diode is made up of a single metal
semiconductor junction. These typically have reverse breakdown voltages in the
3 to 5 volt area. If a "Schottky" diode has a higher Vbr then it's what's
called a "Guard Ring" type. These have a P/N junction surrounding the schottky
junction that increases the reverse breakdown and another P/N junction to
isolate the two forward curves. Sometimes these are made improperly where the
second PN junction gets shorted and then there's a "double break" in the
forward I-V curve and charge storage (slow operation) is associated with them.
When HP first introduced microwave Schottky diodes they put a reverse recovery
time spec on them when in fact it was zero.
For more on Microwave Diodes see:
http://www.prc68.com/P/Prod.html Products I make and sell
http://www.prc68.com/Alpha.shtml All my web pages listed based on html name
http://www.prc68.com/I/WebCam2.shtml 24/7 Sky-Weather-Astronomy Web Cam
Bruce Griffiths wrote:
> Robert Berg wrote:
>>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.
> A PIN diode shunt clamp can be used, however it will take a while to
> respond so some other means to clamp the unwanted energy during the time
> it takes to turn on the PIN diode clamp may be necessary.
> time-nuts mailing list -- time-nuts at febo.com
> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.
More information about the time-nuts