"Tom Ring" wrote in message
.. .
If one has a sealed balun, such as you would pick up at your FLARPS or a
fles market, and the label has disappeared from environmental exposure,
is it possible to easily determine -

1) - if you are sure it's a 1:1 whether it's voltage or current type

2) - given it's totally unknown, anything about it.

Instruments available would be a standard multimeter and an MFJ 259 or
something equivalent.

assuming its a wound balun...
attach some alligator clips to a variable resistor, and set it to around 50
ohms or so - then attach it to one side of the balun. and attach coax from
the mfj259 to the other side.
turn on the mfj and adjust the resistor for low swr (you'll have to measure
it later)
turn it off and measure the resistance you had to adjust it to.
Dividing that value by 50 will probably be the balun's impedence ratio
(4-to-1 - or whatever)
Change freqs on the MFJ and go it over again till you determine the
bandwidth.
(If you adjusted the resistor to 200 ohms and it shows SWR of 1:1, then its
a 4 to 1 balun)
my 2¢
Hal
W4PMJ