Thread: TX-relay
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Old January 9th 05, 11:03 PM
geir knutsen
 
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Do you have a link for the schematics of the PIN diode switching? or can you
send me the drafts?

Geir


"J M Noeding" wrote in message
...
On Sun, 9 Jan 2005 11:56:49 +0100, "geir knutsen"
wrote:

It is one of the Magnetic 8172 on your web.
The plan is to take out the circulator and place the TX relay there
instead.
The LP-filter I`ll probably leave or mabe replace it with a bandpass for
2m.
Link to pa. http://home.online.no/~la8ak/d25.htm

Geir


I might have used a smaller dpdt pcb relay from LA3VW which type is
tested by LA6LCA and LA8OJ, but don't know about the availability and
type, and it is some precautions to make to make it operate properly.
The easiest is always to use PIN diode, the Unitrode UM9401 is a very
easy choice (for the series diode), and the dealer is service minded,
at least they were when I bought some. Demanded 50, but they only had
25, and I later sold most of them to friends around, hi
This type of diode may be used to at least 1kW according to SM5BSZ,
but it is a quite complex switch design to do it, normally they are
good enough for more than 100W. The smaller diode could be 2x BA182 or
2x BA282 or something better in anti-parallel. I prefer the anti-
parallel configuration even if I use some current through the diodes
during transmit

73,
JM
---
J. M. Noeding, LA8AK, N-4623 Kristiansand
http://home.online.no/~la8ak/c.htm