David,
My XYL and I have been away, so my apology for being slow to make a comment.
If your remote Beverages are to be used on 160m, 80m and 40m, and a remote
TRF is used on each band to provide selectivity and gain, then unless their
outputs are combined before up-conversion then obviously you would require a
home-to-remote site link to band-switch the TRFs.
Of course I have no idea as to the level of BC signal(s) etc your Beverages
would present to the TRFs, but as you know the size and mix of all Iron/
Ferrite cores used in the system (including the combiner's) must be chosen
with care to prevent "Core Generated IMD" becoming a "problem".
Another difficulty which might arise in an up-conversion scheme is the
generation of intermodulation products, either by the up-converting mixer or
by any subsequent stage. This makes me wonder whether it would be better to
run the 160m, 80m and 40m TRFs continuously, and view their combined outputs
as "Baseband". Then use this "Baseband" signal to Angle Modulate (FM or PM)
the microwave transmitter at the remote site. At the home site the
recovered baseband from a FM/PM receiver would be the 160m, 80m and 40m
bands. Of course a home-to-remote link would not be required.
Here I must put my hand up, because it has been a -long- time since I
designed any microwave kit, and I cannot recall if a "Baseband" extending to
7.2 MHz is feasible.
Best wishes to you, David, to all on the "List", and to everbody at Elecraft
for the New Year when it comes!!
73,
Geoff
LX2AO
On December 22, 2012 at 2:40 PM, David Cutter wrote:
I want to place Beverages at remote sites (for rx only), for 160m (useable
on 80 and 40m), but it's not viable to use a K0 at each site. Is there a
way to use a simpler system: perhaps a TRF on each band, up-converted to,
say, 2.3/2.4GHz then down-converted to each band for my K3 at home. The
transmit antenna will be at home and listen in diversity mode.
I can see various issues like image and sensitivity cropping up, but I
just wonder if this has be done. It would be nice if there was a lower
cost K series simple remote receiver available.
______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net
This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
