[TowerTalk] 300 MHz Remote Switch

[Jim Lux]

On 12/20/11 6:02 AM, Ian White GM3SEK wrote:
> Pete Smith wrote:
>> Recently, on a whim, I bought one of these
>> <http://www.ebay.com/itm/12V-8-Channel-Way-Relay-Output-RF-Remote-Contro
>> l-Switch-/130545242235#vi-content>,
>> thinking it might be possible to use it to switch beverages at a point
>> about 250 feet from my house.  I knew, of course, that the little
>> hand-held remote couldn't possibly reach that far, but thought maybe I
>> could cobble something up.
>>
> For a receive-only setup, you could easily run the 315/433MHz control
> signal up the coax, along with 12V DC power and the returning signals
> from the Beverages. A few inches of wire threaded under the shield braid
> at each end of the coax (like the old Monimatch) should make a good
> "launcher" and "catcher", and the coax link should deliver far stronger
> signals than over the air between antennas.
>
>

when I was looking at 2.4GHz for HF antenna control, I was more worried 
about overcoupling and having the HF destroy the 2.4GHz stuff (or, at a 
lesser scale, having it saturate the front end).

Say the receiver is designed for signals in the -50dBm range (max...) 
and you've got that 100W RF (+50dBm), you need 100dB attenuation..