[TowerTalk] Balun(s) Testing

[Joe Shuey NE3H]

I am building a 6 meter beam.  I decided on the Antenna book arraingement
of feeding this Yagi with a Hairpin match and a 4:1 balun. I have 3 baluns
on hand. One is an UNADILLA ( unused ), the second looks very much like the
first, but is used and the 3 is one I purchased as part of a 15 mtr
monoband antenna with no outside markings.

I hooked up my old Network Analyzer and a Directional Coupler.  I
terminated the Baluns with a 200 ohm metal film resistor.  When swept up to
100 mhz, the best return loss was, perhaps 12db. I expected greater than
20db. I thought perhaps, that I had an improper setup.

SO I got out the trusty AEA analyzer.  I checked on 21 28 and 50 mhz. The
best SWR that I could get was not reasonable.  The best match I could get
was with a 400 ohm load on 50mhz .. and that was 1.8:1.

Is it unreasonable to expect a decent reading with such low power?  Or
should I suspect that all the baluns are bad?

I expect that I could build a half wave transmission line and get return
losses of greater that 30db.

What's wrong here?

Thanks de joe
73!



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