2013年11月11日 · Using an OHM meter to test continuity on the BALUN's 300 Ohm side to 75 Ohm side reveals different results on different BALUNs. For instance, in one test, the BALUN will show a ohm meter reading if the test probes are attached to the two 300 Ohm pigtails.

2018年9月18日 · The loop for a 300:75 ohm transformer/balun should be 150 ohms. But 150 ohm coax is not available. I used 93 ohm coax for the loop, Belden 9269, as a compromise. Attached is an image of the transformer/balun I made. A couple of ferrite beads should be placed over the 75 ohm cable to improve the balun performance.

2008年2月23日 · RG58 is a 50 ohm cable used for radio communications, such as CB and Ham. Smaller in size than RG59, and VERY different connectors (PL259). For the most efficiency, you'd need a matching transformer to go from a 50 ohm "PL259" to a 75 ohm "F", then a standard 75-300 ohm balun. If you're not too concerned about efficiency, get one of these.

2002年5月30日 · It seems the RS Double Bowtie antenna is very popular in this community due to its low cost and excellent performance. And since it has a 300 Ohm twin lead cable interface, a 300 Ohm to 75 Ohm Coax balun is required. It also seems a lot of people simply use inexpensive baluns such as the RS #15-1140 or the RCA VH54.

2001年11月20日 · Since most TV Antennas have a Characteristic Impedance of about 300-ohms (in reality their SWR is NOT perfect), they need to operate into a 300-ohm load, which is the twinlead input on a Balun. Since the Coax (and Preamp and TV Tuner) impedance is standardized at 75-ohms, the Balun must TRANSFORM from 300 …

2011年12月24日 · A lot of those were designed to allow FM dipole antennas to be connected to the receiver's 75 ohm input. I remember discovering that a Radio Shack push on balun that had two terminal screws for the 300 ohm side connection severely attenuated UHF. I don't know if their current model has UHF frequency response or not

2011年6月12日 · I have done tests on each balun using a VOM meter set in the Ohms range. The various tests were made putting each of the probes on each 300 Ohm wires and taking a reading. Results were some gave a reading and some gave none. Testing the outer shield connector to center conductor gave a reading on some baluns and none on the others.

2019年12月2日 · HDTV Technical. Can we please discuss BALUNs 300 Ohm to 75 Ohm in an easy to understand manner? Jump to Latest

2002年1月11日 · IT is very important when using 300 ohm twinlead that Insulated standoffs are used down the mast and any outdoor runs. Without standoffs YOU WILL have great RFI problems. In most cases it is best to use a 300->75 ohm balun at the antenna terminal and run RG-6 coax as a down lead.

2009年3月15日 · The Radio Shack balun with a push-on "F" connecvtor and screw terminals for 300 ohms, which was designed for adapring an FM "T" antenna, definitely has isolated coils, but unfortunately, its frequency flatness at UHF frequencies is irregular.