More Thoughts on The Flea Market HDTV Antenna

I dug around in a junk box and found a TV transformer and a length of 300 Ohm twin lead. Looking at the frequencies of the local TV channels, they are spread between 506 and 674 MHz UHF. Channel 5 is on 210Mhz VHF. I am thinking of cutting a 1/2 wavelength of the twin lead cut for 580MHz and making a folded dipole out of it. I’ll place the transformer right at the feedpoint. It strikes me that this would work better than the dipole I sourced from the flea market. I’ll build one of these and do an A vs. B test over the next few days.

I may also try a coaxial dipole made from RG-59 or RG-6 coax just for grins as well. That could end up being and even cheaper version that is at least tuned to the TV frequencies.

I figure the cost of making one of the dipoles is around $5 with the transformer being the bulk of the cost. The coaxial dipole would eliminate the need for a transformer. 300 Ohm twin lead for TV is getting hard to find but I am expecting decent performance.

The loop antenna makes some sense as being better than the dipole. It has some directivity, gain and it is better matched to the TV transformer.The crossed loops that are at the flea market would make sense in that they provide a more omnidirectional pattern (assuming that they are properly constructed).

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