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[TowerTalk] Update SWR problems A4S long

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Subject: [TowerTalk] Update SWR problems A4S long
From: kb3aug@juno.com (Bill Hinkle)
Date: Thu, 12 Feb 1998 21:34:49 -0500
Dale, Got a lot of responses.  
           I feed the antenna with a Bencher Balun, not sure what kind,
my guess is a voltage balun. The remote switch is a Ameritron RCS-8V.
Position 5 has never been used, so I switched the feed line over to that
one, no change in SWR at all. To the others who thought it was the switch
this proves the switch is ok. The antenna only uses 1 feed line for
10-40. My 2, 75 meter antennas and the 160 antenna are working fine. The
40 meter part of the A4S is working fine also, worked TT8JFC on the 2nd
call tonight after K3ANS (think he has 2 elements on 40). So that makes
me think the balun and feed line is ok also. Here is how the SWR looks:
14.150 tad over 3 to1      14.250 tad over 3.5 to 1    14.350 4.5 to 1
21.200 3.2 to 1                 21.250 3 to 1                      
21.450 3.4 to 1
28.3      2 to 1                    28.5 2.1 to 1                       
28.9 2.5 to 1           29.7 2.5 to 1
7.150 2 to 1                       7.225 1.6 to 1                    
7.290 2 to 1

I had the antenna set up for the middle of the phone band.
I plan on taking the dummy load out there this weekend and unhooking the
coax at the balun and hook it to the dummy load. I'll see what happens. I
think it's the traps, I have not been able hear the KA4IST/KH5 well
enough to even try to work him, when others in my area have worked him
easy on 20m, With 9M0C and the KH5 that will be 2 that I need and will
not get...Bummer Big Time. I've even been getting up before 5 AM to see
if I can find the KH5 on 40, no luck yet. I did hear VP8CTR on 40 this
morning, but he was not working split.
So, Dale, guess you better send me the info on checking and taking the
traps apart. It sure sounds like that's where the problem is to me.
So what do you all think? If the coax or the balun was bad 40 wouldn't be
working, right?
Thanks to everybody who gave me your advice, ain't this reflector just
the greatest!
I know it's my favorite!

                                                               Up to 237
confirmed and 
                                                               very close
to having the first
                                                               plateau of
150 CQ Zones confirmed 
                                                               for 5BWAZ
                                                               Thanks
again to all,
                                                               Bill
KB3AUG
                                                               Riverton,
WV.......
On Sun, 8 Feb 1998 22:37:10 -0600 "Dale L. Martin" <kg5u@hal-pc.org>
writes:
>Bill,
>
>What have you got at the A4S feedpoint?  A ferrite balun?  a
>coiled coax balun? (I have two A3's and use coiled coax
>baluns--no problems).
>
>If you can't get up the tower to check the SWR (do you have
>access to an MFJ-259 or equivalent?), you may be stuck until
>warmer weather sets in.
>
>One thing you might do is take the remote coax switch out of the
>loop and see what you get with a direct feed.  Just because the
>other positions are reading okay doesn't guarantee the A4S
>position is good.
>
>Second thing you might do is remove the coax connector from the
>antenna at the coax switch--I've seen water come out, even with
>the connector on.  If the coax end looks clean, then put on a new
>connector.  At least, you have confirmed that the system is good
>through and to the coax near the remote coax switch.
>
>If you can get up the tower, and it's not too tall, you might
>take a run of coax (rg58?)
>up and do a temporary replacement of the old coax to verify the
>original coax is not bad.  Another way is to disconnect the coax
>at the balun, connect a dummy load and have someone key the
>transmitter through the bands and check swr.  If it's flat on all
>bands, consider the coax to be good.
>
>Fortunately, if it is the antenna at fault, you only need to drop
>the driven element to check it out on the ground.  If you get
>that far, I have some information on checking, disassembling, and
>repair the traps...even what the resonant freqs of each should
>be.
>
>Let me know if you need the info....be happy to e-mail it to you.
>
>Good luck,
>
>73,
>Dale, kg5u
>kg5u@hal-pc.org
>
>

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