A lot of early simulcast systems "didn't work" because the designers
ignored problems of time differential interference in overlap areas. Or
ignored problems of transmitter stability, audio level equalization.
Small things like having the audio phase 180 degrees out of phase (doh,
signal wires transposed!), CTCSS tone out of phase. A lot can go wrong
and the product still be solid. That is what I am wondering.
I understand RTCM TX Simulcast addresses all those concerns, but they were unhappy enough with the result to announce it "non working", which is a great loss to me. I've not heard or seen a demonstration of this - maybe someone has a video of it, or might offer an anecdote.
By the way if you have a high site, lots of ERP, no reason not to use
voter for multiple antenna diversity co located on the site. No back
haul needed.
Those places are getting expensive here. I like the voter idea, because we can reuse inexpensive sites - and just add more of them. Receivers and Ubiq radios are cheap as chips, and you can just throw one into any gap, with a big antenna and a quality preamp on it. That'll work. 
I am with you on digital audio CODECs. I am not sold. But there is
something to be said for 15 sites of DMR 2-slot TDMA linked with
internet and mobiles free to roam automatically.
We could do better in my opinion. The interesting thing about any Voter system, is that the receivers do not have to be sited with their transmitter. So lots of problems go out the window. No duplexing and no power limitations are the big ones... Imagine what you can do on a 6/2/70 repeater site when there is no duplexing and no power limitations! 1500 watt analog repeater, anyone?
Single-site digital systems have similar advantages, again no duplexing and no power limits. Cue 100watt 1.3GHz 10mbit for Hams? Multi-site zero-handoff all done in software?
Really great tech chat, Joe. 
Steve
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On 31/03/16 13:26, Joe Leikhim <rhyolite@leikhim.com> wrote: