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4x Array's 50 ohm DUMMY LOAD ?

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Subject: 4x Array's 50 ohm DUMMY LOAD ?
From: aa4nu@raider.raider.net (Bill W. Cox [AA4NU])
Date: Sun, 14 Jul 1996 23:55:59 -0500 (CDT)
Hello !

If you are using a 4x array, what are you using for the "50 ohm port
dummy load" ?  Here's why I am asking this question ...

Was doing some work here on the 80m 4x array and discovered something
of interest ... and you might want to check this out on your array ??? 

I was using a MFJ-260-B 'dummy load' on the 50 ohm port. It had been
in service for several years ... so I decided to check it's condition.

What I discovered was that it was NO longer a 50 ohm load, but now
measured 127 ohms on my Auteck RF-1.  A new MFJ-260-C measures 50 ohms
on the same RF-1 for comparison ... Opening it up showed it to have
been VERY HOT for some time or so it looks. 

I have never measured just how much power was going into the DL, the array
was completed just before a contest. The SWR curves were OK, and the
performance of the array was FB ... So I never checked it ... just one
of those things that you mean to, but never make the time to check out.
You can bet I will now !

So ... Two questions

1. What are you using on your array for the 50 ohm dummy load ? Power rating ?

2. How much power do you see going into your 50 ohm DL on CW and SSB ?


Thanks for any suggestions !  Hope to work you on the low bands soon ...
  
73 Bill AA4NU   aa4nu@raider.raider.net









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