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Old 11-16-2017, 11:43 AM
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DavGoodlin DavGoodlin is offline
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Join Date: Aug 2011
Location: near Strasburg PA
Posts: 3,400
I did extensive antenna testing since moving here in 1989, testing all manner of antennas all on 40-foot Rohn Towers. The VCR's had all the possible channels programmed in, even Washington DC's 4-5-7-9 and a rotor was a must. On a few memorable summer nights, every VHF channel showed a picture here, while some were BW only, others made no sound! On extra-special nights and summer mornings - with e-skip New York channels over-powered Baltimore-DC, while New Haven and Hartford stepped all over KYW-3 and WGAL-8, no small feat!!!

Adding mast pre-amps, knowing the effect on cheaper amps from image frequencies of nearby FM flamethrowers, I was able to select equipment because I could S-E-E what was happening a Sony KV-1711 or Magnavox T995. I even saw effects of radiated noise and interference from switch-mode power supplies. No more.

I had the key benefit of knowing how analog reception was here before the shutdown and only the frequencies have changed NOT the transmitter locations. Appalachia, these Blue Mountain and Pocono foothills and even most of New England is similar this way. Good UHF over 40 miles away required an amp, including Philadelphia UHF's.

In a 1962 PF reporter, I read with nostalgia how Winegard and JFD antenna full page ADs touting the Midwest's VHF reception over 200 miles. Channel 13 of Toledo received in Milwaukee was in one ad, 248 miles! That dealer sure was proud, I bet.

Out of all the "local channels" for this market area, WHTM is the elusive one like WOIO is in Cleveland, every area has at least one problem channel that drives the minimum acceptable installation, and its usually VHF.

WHTM was RF 27 in analog days, but was still a bugaboo to get 40 miles away unless the rotor was dead-on for 27, ABC default was WPVI-6. Normally, all but channels 4-5-7-9 was receivable on my 1967 Philco hybrid color, using built-in rabbit ears , but only up in the attics of both our 2.5 story houses. This is how good it was compared to WHTM.

Low rolling and wooded hills west of Philly are small but biggest factors affecting digitized RF are nearby trees, not reflected signals. Multipath was not a problem due to agricultural surroundings, so increasing antenna elevation is mostly used to overcome near-obstacles like trees, and equally important, reduce terrain-reflected noise.

The distance factor is why Antenna rabbit or antenna web shows "one edge", not line of sight, reception for all the Philly and Baltimore Stations.

The VHF signals for the ABC channels in Harrisburg-10 and Philadelphia-6 (with 2-3 subs each) are generally hard to get without an outdoor fringe-rated VHF antenna. Forget using anything else, even the little broadband ones like "Radio Shack's VU-90, or the ones sold now by CM that are similar.

Believe it or not, the most reliable local ABC reception is from WMAR, which was VHF-2, now DT RF-38. But that is in a different direction.
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Last edited by DavGoodlin; 11-16-2017 at 11:48 AM.
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