"Frank" wrote in message
news:01c3d64b$7ee7fd50$0125250a@uoxijbkdrvrqabcc.. .
Dale Parfitt ...

^ If by Tee, we are not talking about s proper 2 way splitter,
^ the loss at certain freqs can easily be 20 dB or higher.

^ This would be where a coaxial line to the other radio
^ appears open and is also a 11/4 wave electrically-

Do you mean the frequency that the length of the patch cable is
electrically
eleven-fourths waves? If so, then just keep the length of the patch cable
less than:

300/FREQ*11/4

So for 868 MHz:

300/868*11/4=0.95m

A little shorter than a meter. No problem. Just use the formula on the
highest frequency you receive.


^ In addition, phase noise, and L.O. leakage from each radio
^ can be impressed on the other, raising the noise floor.

I've been running multiple scanners on an antenna for many years now and I
have not noticed ANY additional noise and no apparent local oscillator
trouble. The only problem I've observed is minor signal loss that is only
apparent when receiving very weak signals.


^ This is very poor engineering practice- and not good
^ amateur practice.

No, good amateur practice is to buy the most expensive antenna system you
can
afford -- for transmitting.


^ CATV/MATV splitters usually have good preformance down to
^ HF; i.e. insertion loss, splitter balance, and port-port
^ isolation.

Thanks! But don't they come with F-type connectors? The loss from BNC to
F-type adapters that would be necessary would probably nullify any
benefit.

Frank


Little typo on the coax length- should have been 1/4 electrical wavelength-
you have to take into accont the velocity factor.

Although I have not done this recently, I think I can safely say that the
loss in a pair of F-BNC connectors would be well under 0.5dB at 800 MHz.. I
can put a pair back to back on the network analyzer and confirm this if
anyone is interested.

Dale W4OP