CMC TEST - BALUNS

ZERO BALUN

1:1 GUANELLA, 50 OHMS

B2 - 1:1 GUANELLA, COAXIAL BALUN

This is a Spiderbeam 1:1 Guanella (Reisert) Balun, as used in the Spiderbeam Yagi antennas.

The main reason for choosing this balun is, I already have one built.

This is normally used on 20 thru 10m where its impedance is greater than 1000 Ohms, but it still has an impedance of about 500 Ohms on 40m.  If I build another one before the tests begin, I will add a few more turns of coax.

(The two connections on the top will not be used.)

B3 - 4:1 GUANELLA / DUAL CORE

This is my "Standard BALUN" for OCFD antennas.

B4 - 4:1 GUANELLA / DUAL CORE TP

This is identical to B3, except this one uses Twisted Pair wires.  The reason for using twisted pair is simple; I can buy the wire in twisted pair and don't have to tape the wires together.  Theoretically this is not as good as when the wires are taped in parallel.  But how much worse is it really?  Is it worth the extra effort to use parallel wire?

All else is identical to B3.

B5 - 4:1 GUANELLA / SINGLE-CORE

Theoretically this balun will not work.  It will not produce equal current in each antenna half.  Yet it is being sold in this configuration by many commercial balun companies.  How much worse is it really?  

The main justification for this design is size, weight, and cost.  

The physical shape may differ but the balun core and wiring will be the same as pictured.

B6 - 4:1 GUANELLA / DUAL - CORE

This balun uses two cores, with each transmission line having its own dedicated core.  This assures equal current will be forced into each leg of the antenna.

The cores used in this balun are a little smaller than the core used in B5 above.

B7 - 4:1 Guanella / Dual Core

Internally, this balun is identical to B6 (above).  

I had a local company build it into one of their enclosures for me. It looks good, functions great, but it is too heavy.  

The two toroids together weigh just 42 gr. including the wire.  The enclosure and SO-239 weigh 227 gr., bringing the total weight to 269 gr.  A nice balun, but

MUCH TOO HEAVY  

for using with lightweight fiberglass poles.

B8 - 4:1 Guanella / Dual Core

Internally identical to B6 & B7 (above).

B9 - 4:1 Guanella / Dual Core

Internally identical to B6 & B7 (above).