Topband: Antenna switch rating for high SWR?

[Joe Subich, W4TV]

> I know that T/R switches inside amps are fairly small in physical
> size, however they are designed to operate into a fairly low SWR
> load. I have no idea of what rating of a DPDT switch I would need
> (per the diagram) in my application - perhaps I'm making a bigger
> deal of something that isn't so critical.?

Fire up ELNEC or your favorite modelling software and run your
specific combination of flat-top length/height and feeder length
to find out what the voltage and current are at the input of the
feed line.  That will tell you what you need for the relay.

Remember, you can use *TWO* high voltage/high current "contactors"
and mount them on Lexan or similar non-conducting surface to increase
the voltage to ground rating if necessary.

73,

    ... Joe, W4TV


On 10/20/2013 12:04 PM, John Harper wrote:
> Morning all,
>
>
>
> I am planning to put in a DPDT switch (or relay) to allow me to easily
> switch from using my 80m dipole as a vertical (T-top) antenna on 160m:
>
> http://www.ae5x.com/docs/antennas/160mT.jpg
>
>
>
> The dipole is fed with 450-ohm ladder line and used 10-80m in that
> configuration so there is a high SWR on the line. I sometimes use a kw
> output.
>
>
>
> I know that T/R switches inside amps are fairly small in physical size,
> however they are designed to operate into a fairly low SWR load. I have no
> idea of what rating of a DPDT switch I would need (per the diagram) in my
> application - perhaps I'm making a bigger deal of something that isn't so
> critical.?
>
>
>
> John AE5X
>
> http://www.ae5x.com/blog
>
>
>
> _________________
> Topband Reflector
>