Thread: my SWR reading
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Old October 27th 07, 12:55 AM posted to rec.radio.amateur.antenna
charlie charlie is offline
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First recorded activity by RadioBanter: Sep 2006
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Default my SWR reading

James Barrett wrote:
Hi, I just got my new (used) HF rig, and I strung up a half wave dipole
for 10 meters using 28.4 mhz in my calculations. Several hours later I
am getting an SWR reading of 2:1 at 28.4mhz. Is that pretty good or
should I try to do better?

I appreciate any opinions.

Jim

Jim,

whatever the in and outs as discussed in this thread, if you cut and
resonate at 28.4, have the dipole at a decent height, feed it with
50 ohm coax you should get better than 2:1. Do you know what the
actual resonant frequency of the dipole + feeder is?

As an example I have a ten metre dipole in my loft, some 25 feet
above ground. It resonates at 28.44 at the end of approx 10 metres
of 50 ohm coax, the SWR is 1.4:1 . The bandwidth at 2:1 is 28.25
-28.63. At 2.5:1 it is 28.160-28.760. This is before the ATU, after
the ATU the TX sees from 1:1 to 1.4:1 over the whole of ten metres.
See http://www.radiowymsey.org/FanDipole/FanDipole.html


Charlie.

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