Re: IC-705 antenna switch from band
If your goal is to simply switch between a single multi-band HF antenna and a dual band VHF/UHF antenna, the losses of a single duplexer could be easily overcome by using higher-gain antennas or lower-loss feed line. A single duplexer has very minimal losses, for example, this Diamond duplexer has about 0.2 dB signal loss maximum:toggle quoted messageShow quoted text
If you decide to employ a CI-V interface, a band switch and antenna relays, you will incur a significant expense ($200?) and still have signal loss (no switch I'm aware of has NO loss). For example, this popular Ameritron RCS-4 antenna switch has 0.1 dB loss at 3.0 MHz:
Don't like MFJ/Ameritron? How about this SSB Engineering part, which is better suited for applications that include both HF and UHF band signals? It has a specified 0.15 dB loss/attenuation:
I like the low cost ($75?), simple, duplexer option for remote operation, it requires zero interaction by the operator, and can be placed anywhere along the feed line, potentially saving on feed line expenses.
My advice, take another look at the losses involved - you may find the popular concern about loss to not be nearly as bad as others suggest.
Final note - even a simple, mechanical coax switch - which would be impractical for a remote setup -has about a 0.12 dB insertion loss:
Daiwa CS-201A 2 Position Coax Switch
It looks like the only way to avoid signal loss is to manually switch coax connectors as you switch bands.
On Jan 18, 2022, at 08:16, Mark Kyle <kylecom@...> wrote: