Nate:

As often happens, I find myself agreeing with what you say.

I'm wondering, however, if anyone has configured D-Star systems with 
separate antennas and no duplexers. We have a UHF analog system here 
that's astounding in how it performs that's built this way with a 
high-level preamp at the RX antenna and that shares transmission line 
with the VHF at the same site. I've been looking for combined VHF/UHF 
antennas to consider for our district D-Star project to see how the 
pricing comes together.

Chances are we'll be required to have circulators at the sites we're 
considering anyway, so we're looking at the following possible 
configurations

* TX circulators
* Pair of dual band antenna configurations or dual separate antennas 
with band combiners
* One TX transmission line (7/8" or larger)
* One RX transmission line (LMR-400 -- remember the preamp is at the 
antenna)
* Preamps with bandpass filters

The advantage of this would be that we'd only run one large transmission 
line for both VHF and UHF TX (suppose we could also share with 1.2G if 
we were doing that), it would use cheaper and lighter transmission line 
for RX, doesn't need duplexers, does have a bit more antenna, but also 
has about 12 dB better receive and less transmit loss.

So, while we're talking equipment I thought I'd throw that out there to 
see if anyone is using or considered this approach. I'm not convinced 
yet that the overall price will end up that much better, but that may be 
outweighed by performance. Just curious what people think about this.

I would also echo Nate's comments on the Sinclair antennas. Have always 
been impressed with them and have had no problems at all.

Chuck - N8DNX
[email protected]

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