Note. From the ARRL Newsletter 9/19/2013. Palomar Engineers President John E. "Jack" Althouse, K6NY, of San Diego, California, died September 15 after suffering a massive stroke. He was 90. Palomar Engineers, the Escondido company he operated, may become a thing of the past as well. A message on the company's website says Palomar Engineers is "temporarily closed" and "not taking orders at this time."
This is a 4 to 1 with 12 turns of #16 Teflon covered magnet wire on a Palomar F140-6 core. The ideal, according to what you read on the Internet, is 14 turns but I ran out of room. Housed in a weatherproof electrical box from Lowes. ( As of today, 9/15/2013 the Palomar Engineering website is down. Hope they did not go out of business?)
Click on images below for a larger Graph
Balun terminated with 200 Ohm resistor at antenna terminals
RigExpert 54 MHz scan. OCF, 38% from one end fed, 80 Meter length, 35 foot elevation.
This balun was built as my putty knife balun at this page. The only difference was the wire gage and core. The balun was installed in a small Radio Shack Box ( Part # 270-1803 ) Construction was identical to the Lowes electrical box on the top of this page.
Click on images below for a larger Graph
In box. Terminated with a 200 Ohm carbon resistor.
The plot above is the Z=R=jX selection on the RigExpert. Same conditions as in the VSWR plot / Fo above.
Plot above is with test OCF wires installed at 35' elevation.