Towertalk
[Top] [All Lists]

Re: [TowerTalk] Polyphaser

To: "Tower and HF antenna construction topics." <towertalk@contesting.com>
Subject: Re: [TowerTalk] Polyphaser
From: "Roger (K8RI)" <K8RI-on-TowerTalk@tm.net>
Reply-to: "Tower and HF antenna construction topics." <towertalk@contesting.com>
Date: Wed, 17 Mar 2010 09:02:37 -0400
List-post: <towertalk@contesting.com">mailto:towertalk@contesting.com>

Rick Stealey wrote:
>  how do I check out the unit to know if its 
>   
>>> still good?
>>>
>>>       
>
> You take a power supply that puts out 800-1000 volts, put a very large 
> resistor in series with a microampmeter, and attach it to the output coax 
> connector (the antenna side).  There is a gas tube inside from this point to 
> ground. 
None of mine have gas tubes. They have a solid state device.
>  It is an open circuit until the breakdown voltage is reached.  So as you 
> crank up the voltage and watch the ampmeter suddenly it will go from zero 
> current to a value limited by the resistor.  A kw polyphasor will begin 
> drawing current in the 600-800 volt range.  
> If it is blown it will never draw any current.
>   
Or it'll be a dead short.

The ones I've had fail did neither. The only indication was a high SWR.
Stick an antenna analyzer on it with a dummy load on the antenna side. 
If the SWR is high it's bad.
It may actually require power to show it's bad. The two I had that were 
bad, "heard" signals just fine, but when I'd transmit the SWR was about 
5:1 when it was otherwise around 1.2:1

73

Roger (K8RI)
> I didn't look up the model number of your unit to see if it is a 2 kw or a 
> low power unit.  The high power one breaks down as I indicated above and the 
> low power one probably in the 300 volt area (give or take a couple hundred 
> volts !)
>
> Rick  K2XT
>                                         
> _________________________________________________________________
> Hotmail is redefining busy with tools for the New Busy. Get more from your 
> inbox.
> http://www.windowslive.com/campaign/thenewbusy?ocid=PID27925::T:WLMTAGL:ON:WL:en-US:WM_HMP:032010_2
> _______________________________________________
>
>
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
>
>   
_______________________________________________



_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk

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