[Elecraft] KAT 500 Loses Match

[David Gilbert]

Fully agree.  The specs for the CHA-250B say a maximum of 75 watts for 
digital modes ... i.e., continuous duty modes.  That pretty much says 
what the actual heat dissipation capability is.  If he was trying to put 
500 watts into his antenna in almost any mode, it is probably toast ... 
figuratively and literally.

Dave AB7E


On 1/14/2024 8:17 AM, Morgan Bailey wrote:
> The Cha250 b is NOT an antenna capable of greater than 100 watts for any
> length of time. It is a 5:1 unun hooked to a 23 foot aluminum radiator. It
> needs to be 30 feet in the air and if that happens it will function like a
> vertical OCFD. Still it is only good for 100 watts. When running a tuner
> with the KAT500 and KPA500 you are heating up the puny unun and the cores
> are totally being fried. Plus the reactance probably is generating high
> voltage on the short radiator causing arcs across any of the many
> connections inside the matching section. A guy fried a base section and I
> have it in the garage. That is your problem. I have owned 2 of the antennas
> and as such they work in a pinch and work well for fast POTA activation
> with 100 watts but other than that they are pretty much a megga compromise
> antenna. You would be way better off with a 998 mfg remote tuner and a 43
> foot vertical over a radial field. Check out the Zero5 antennas for the
> cheapest durable 43foot vertical solution. 73, Morgan NJ8M
> BS + MS + $2.98 = COFFEE
> Real Life Experience = Priceless, says the man who set his back yard on
> fire with a breadboard tuner loading a 160 meter inverted L with 1000
> watts. LOL
>
>