I have also measured the SWRs with a completely different set of coax to
eliminate coax and/ or connector problems. No difference.
73,
Bernard, WA4OEJ
----- Original Message -----
From: "Tim Duffy K3LR" <k3lr@k3lr.com>
To: "Bernard(wtrone)" <wtrone@comcast.net>
Cc: <towertalk@contesting.com>
Sent: Saturday, August 28, 2004 4:16 PM
Subject: Re: [TowerTalk] Perplexing Antenna Problem
> Hello Bernard!
>
> Given the your information I would suggest that the PL259 on either end of
the cable is bad (does not show up until you have more 1 watt or more going
into the coax). The PL259 on the far end would be the best place to start.
It may be intermittent, as when you have the 50 ohm load at the antenna end
all looked OK.
>
> You could have a problem with the SO-239 at the SteppIR as well.
>
> Or, the coax could be crimped somewhere along the line (less likely).
>
> Please let us know what you find!
>
> 73,
> Tim K3LR
>
> "Bernard(wtrone)" wrote:
>
> > I posted the following message on the Yahoo SteppIR board and
thought that I might also get some ideas on this board.
> >
> > I have an interesting problem for all of you antenna experts out there.
If you have been reading this thread (Yahoo SteppIR board), you know that I
have been having problems with my new SteppIR 3 element beam. I was able to
borrow a MFJ-259B this morning and made a relatively extensive set of
measurement, which taken as a whole, just do not make sense.
> >
> > In summary (2 measurements on 20, 1 on 17, 2 on 15, 1 on 12 and
2 on 10M for each series of readings):
> >
> > 1. Set of measurements using the MFJ with a 20" length of
coax to the SteppIR. Measured from 20-10M SWRs of from 1.5:1 to 1:1 (also
have the R and X measurements but won't go into those just yet).
> >
> > 2. Set of measurements using the MFJ in the shack using the
full length of cable to the SteppIR. Measured from 20-10M SWRs of from
1.4:1 to 1:1.
> >
> > 3. Using MFJ to measure Coax Loss from 20-10M showed 1.3 to
1.6 dB. Probably about 135 ft of cable.
> >
> > 4. Put the cable in the shack directly on the antenna
connector of a Daiwa NS-660PA SWR and Power Meter, and the SWR is 5:1 from
20-10M. The reading on the TenTec Orion is high VSWR. Take the PL-259 off
the SteppIR and put it on a 50 ohm dummy load and the SWR is a flat 1:1
across 20-10M both on the Daiwa and Orion.
> >
> > 5. Tried varying the "tune" power of the Orion from about 1
watt to 50 watts. No difference.
> >
> > 6. Tried taking the Daiwa out of the circuit. No
difference. Orion still reads high VSWR.
> >
> > 7. Swapped out a complete set of coax cables to insure
nothing was common. No difference.
> >
> > Anyone out there in radio land have any ideas? I am going to talk
to Jim on Monday, but this is really a STRANGE set of data. I am a bit
perplexed with what I am seeing!
> >
> > 73,
> >
> > Bernard, WA4OEJ
> > _______________________________________________
> >
> > See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any
questions and ask for Sherman, W2FLA.
> >
> > _______________________________________________
> > TowerTalk mailing list
> > TowerTalk@contesting.com
> > http://lists.contesting.com/mailman/listinfo/towertalk
>
>
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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