Topband
[Top] [All Lists]

Re: Topband: More - lightning protection on 4 sq

To: "Rick Stealey" <rstealey@hotmail.com>, <topband@contesting.com>
Subject: Re: Topband: More - lightning protection on 4 sq
From: "Harold Smith" <w0rihps@sbcglobal.net>
Date: Fri, 13 Jun 2008 09:18:06 -0500
List-post: <topband@contesting.com">mailto:topband@contesting.com>

>
> According to my calculations at 2 MHz:
> If the capacitor in series with the line inside the Polyphasor was .01 uf 
> it would have a reactance of 8 ohms and the phase shift would be 9.15 
> degrees.
> If it were 0.1 uf the phase shift would be 0.93 degrees.
> I got those angles by making a right triangle with 50 ohms on one side and 
> the reactance value on the other, and figuring out the size of the angle 
> (tangent = opposite/adjacent).
>
> Yes, not something to be ignored until you open it up and look inside.
>
> Rick  K2XT

Hello Rick:

I opened a Polyphaser IS-50UX-C0 and it had 2 small disk ceramic capacitors 
in parallel.
I couldn't read the values by sight so I measured the value. It was 0.02 
mfd. So each capacitor was
a 0.01 mfd. The physical size looks like standard 600 volt disk capacitors.

The Polyphaser rating on the unit is 2.0 KW at 1.5 to 50 MHz and the rating 
drops as the frequency increases to
125 W at 220 to 400 MHz. In between is 375 watts.

Regards .

Price W0RI 

_______________________________________________
Topband mailing list
Topband@contesting.com
http://lists.contesting.com/mailman/listinfo/topband

<Prev in Thread] Current Thread [Next in Thread>