Wolf:
I already
considered building a battery-powered remove RX with a 70cm-FM-link to the
main station (using a cheap 70cm-LPD handy). The problem is finding a
quiet
remote RX side where the RX cannot be vandalized or stolen.
I have been doing this now continuously for the last 11 years and have done
it for about 18 years over the last 40 years.
I have used both linear upconverters as well as Receiver Audio to FM
transmitters. I have never had any of my active equipment stolen, I once
lost the exciter, driver, and power supplies for an EME station I had at a
remote site.
I have in the last two years used both fibre cable for the back haul as well
as an infrared link (infrared is no good in the daytime hi). My distances
have been from 1000 ft to over 20 miles. Your biggest issue will be to get
all the S+N/N ratio that you can manage - my LF QSO to Europe last winter
was partially backhauled on an FM link on 443 MHz from the remote ICOM 706
MK II G I was using. I regularly use some surplus cable television
equipment that distributes via Fibre Optic cable, it works well and the
transmit end is very low power. I can get three weeks of continuous service
out of a very large truck type battery between charges.
My HF CW station is always remote controlled for the last 11 years now.
There are some very low power SAW filter FM rigs on 433, 418 MHz and 902-914
rigs - they are rated for only a few hundred yards. Some of us have put
surplus Cellular amplifiers to bring these up to about 6 to 8 watts output
and they are great over a 5 mile path. You might find these very useful.
If you have any specific questions let me know, I will try to help out.
Larry
VA3LK
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