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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