[AMPS] QSK5 Unit

[George K. Watson]

>>€  Correct.  The max allowable inverse for a PIN diode is c. 1000v.
>>RJ-1A and HC-1 vacuum relays are typically 5000 piv - and they can
>>recover from a static discharge - unlike PIN diodes.  The  switching
>>speed of these two vacuum relays is under 2mS if a speedup circuit is
>>used.  See my Web site for details.

Since the statement above seems to posit that there is only one kind of
PIN diode in the world, I feel compelled to respond as someone who has
designed with and uses PIN diodes in amateur radio and professional
applications.

There are available from MACOM PIN diodes with a PIV of 3kv. Several MRI
machine manufacturers use them in their machines. These diodes are very
expensive, though some are starting to show up in salvage. Since I typically
ground everything in the shack via mechanical coax switches, when I am not
operating, I have had no problem with lightning. I live in a very
electrically
active area, in the mountains above Boulder, CO, and so far have not lost
any
PIN equipment. The circuits to work with PIN diodes are much more
complicated
than with relays, but if you need the speed...

73,
George K. Watson
K0IW


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