In a message dated 5/4/00 11:41:17 PM Eastern Daylight Time,
jono@enteract.com writes:
>
>
> on 5/4/00 10:09 AM, measures at 2@vc.net wrote:
>
> > I have never seen such a thing. The big variable is duty-cycle. For
> > example, RG-213/u typically runs comfortably warm with 15k on 14MHz using
> > unprocessed SSB-Voice. However, switch to RTTY, and 15k makes it run way
> > too hot.
>
> I agree with you on this, Rich. Sure there is a "maximum power handling"
> capability and that may be specified usually as a CW rating. IMHO, one of
> the real numbers you need to look for is voltage breakdown in the
> dielectric.
>
> 73,
>
> Jon
> NA9D
>
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Running maximum legal input power and assuming ~ 750 Watts key down output,
the "real numbers" you need to look at for voltage breakdwon in the
dielectric is....194 Volts (assuming a 50 ohm system). Not much danger I
would say as I conduct 4,000 volts over a RG-59U coax cable from my power
supply.
My application is a 12" run of coax from the output of my Pi-L tank to the
vacuum antenna relay which could handle at least 1500 watts out, key down.
I was amazed at the number of responses to my initial query telling me that
these figures were contained in every ARRL handbook. I have yet to find
POWER handling capacity in any ARRL handbook. Thank you to all who responded
with sources of this information....I now have it.
Dave, WT8R
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