[ICOM] Pro II protection needed from nearby transmitter?

[Dave Edwards]

I am sure that during several years of PRO series rigs being involved with
Field Day, we would have heard of problems involving blowing out front ends
because of nearby RF energy.
True, less likely that KW's are used in the tents, but the antennas are
often within a few feet of each other!
I'd throw my coax switch to ground anyway to be safe when off the air!

....Dave

----- Original Message ----- 
From: "Paul Ferguson" <Paul at PaulFerguson.us>
To: "ICOM Reflector" <icom at mailman.qth.net>
Sent: Tuesday, March 01, 2005 8:36 AM
Subject: [ICOM] Pro II protection needed from nearby transmitter?


> A ham recently moved into the house next to me. Our antennas are
> about 75-100 feet apart and we both have amps capable of 1 KW.
>
> One evening I noticed that my SWR meter was moving, but my
> transceiver was off. It did not last long, and I did not get a good
> look at it to see the reading. I suspected it was from his signal.
>
> Last night he told me that a second FET in the front end of his TS-
> 2000 receiver blew out.
>
> Here is part of a message he sent me:
>
> > I confirmed that you and I are probably inducing a fair amount of
> > energy into each other's antennas when we're running high power. With
the
> > 40m vertical connected I saw over 5 watts of reflected power indicated a
> > few times a little after 10:30PM. I looked over the schematic for the
> > preamp board in my Kenwood and found a suitable place to put some
> > protective diodes. Kenwood should have done that to begin with - it
turns
> > out that I'm not the first one to lose preamp FETs in a Kenwood TS-2000,
> > so it looks like a bit of a design flaw or oversight.
>
> Has anyone had similar problems with a 756 Pro II or can comment on
> protection in it's front end?
>
> 73,
> Paul
> K5ESW
>
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