BATC Forum

I'm wondering about front end protection for simplex DATV operation, especially for 2M use where the talkback is on the same band and may be at quite high power.
For HF I found this article: http://www.ad5x.com/images/Articles/FrontEndProt.pdf all of which makes good sense. But at rising frequencies won't the limiting diode junction capacitance to ground provide a significant path to ground, so reducing the hard earned received signal?
At the moment I'm planning on a horizontal beam for DATV and a similar one for talkback, but vertical. 'Theoretically' that should give 30dB of attenuation, possibly more depending on actual sidelobes and how they interact etc.
I picked up some DowKey coaxial relays at the recent CATS bazaar and their spec is -40dB isolation and have a good supply of the RS coaxial relays that they used to sell which probably have a similar spec.
How have people set up their receiver(s)(such as Minitiouner, RTL or Pluto) and the matching band linear amp / antenna?
Lots of quality RF relays and sequenced switching (Like Portsdown already does) or what?
Comments and guidance very welcome - I've not killed anything YET, mainly by swapping leads over. But not the ideal solution....

Gareth G4XAT

On 2M I use a mutiband vert for talkback ..which of course completely kills the incoming rx signal ..but 2M frontend is unprotected and remains intacct.

On 23cms I do not trust to a relay as I have had preamps fail using the usual SMA GHz relays ...doesn't take long to screw unscrew an N connector!

For 23cm repeater look through I have two yagis physically separated by < 1 M and an interdigital filter on rx leg..all works well.

Thanks for the 'it works for me' scenario. As I posted I haven't killed anything YET and I want to design in as much as is necessary. It it works then thats fine by me. Noted on 23. I think I'll aim for 6/4/2 next year, and some 3.6 GHz where I have a diplexer for the band.
Gareth