Ah yes, channels 21-99, but +/-75 is not too wide to space stations 400KHz apart.
We do it with Translators and LPFM's, though the good old boys clubs delayed it as long as they could.
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Wmfn 640
- Thread starter cyberdad
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We do it with Translators and LPFM's, though the good old boys clubs delayed it as long as they could.
These were 88-108 MHz allotments, and I think they were 221-300. I'll let you know when I find which Yearbook I saw it in. I've seen a receiver recently with the old 42-50 MHz band, and it had the channel numbers to which you refer. They said they were going to fix it, but I don't know if he ended up trashing it.
They cut back from 250 kw to 100 kw. The coverage outside Mexico City and the suburbs was no longer useful to them.
Very interesting David. XEW certainly was a powerhouse in those days. I could hear it at home in the Chicago area at night even though CHML was much closer. In fact in the evening the later it got XEW would usually get stronger.
The way it is on the first twenty channels where we have
a disproportionate number of signal challenged stations.
Look at NYC, a lot of reserved band station's but only one full class B in a weird location.
Even the UN allcation became a pair of time-shared B1's.
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The problem was, and even now, the Channel 6 protection rules. So even though the B and B1 on 88-92 MHz are only protected to the 60 dBu, unlike 92-108 MHz, where it would be 54 dBu and 57 dBu, it wasn't until relatively inexpensive software made it easier to figure out how to comply with the Channel 6 and other rules that all the lower power drop ins on 88-92 appeared. Again, it was the FCC dropping in the new B1 and other classes that forced many stations down to lower classes. This continues today with other Classes like the newer C0 spacings. Many stations dropped to C1 years ago. Not all bad, because many stations no longer had to be tens of miles away from the COL to be 100 kW.
About 20-25 years ago, I worked with an applicant to figure out how to comply with the NCE FM Channel 6 rules. It was a lot of rereading and headscratching and drawing scenarios out. After getting a few of these approved and on the air, and leaving some of the top engineering consultants scratching their heads after trying to say "you can't do that", they stopped trying to stop it and started using the rules themsleves. Particularly the V polarization only and the mixed H and V polarization with very low H ERP. The rules were particularly onerous near the Grade B analog contour of a nearby Channel 6. Like you say, a lot of the restrictions on 92-108 MHz are to prevent competition. The 88-92 MHz NCE FM band is less restrictive, and that IS the reason for all the drop ins, for better or worse. No doubt, many of these would have been commercial if the rules allowed more flexibility.
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I can't remember the last time I heard XEW here. I used to hear them relatively often. Of course the channel being opened up to nighttime operation for class D stations also has a lot to do with XEW's absence. Last time I was on 900 one pre-dawn morning a couple of weeks ago, I was hearing WDLS from Wisconsin Dells, WI. 220 watts non-directional nighttime from about 130 miles north-northwest of me.
I remember reading something back when vertical and circular polarization fell into favor to the effect that
"a station can add a vertical signal that is not greater than its horizontal signal"
I guess things have changed. I always thought that WAYS was a misprint.
BTW...if you scroll to the bottom of that linked page,
W288BD also looks like an 800 watt misprint.
NCE FM is different. But nearly every case I ever saw with V ERP > H ERP was for Channel 6 protection. Translators and Boosters are also different. I don't recall a commercial band station with V ERP > H ERP.
Of course, not in the US, but I ran all of my FMs in Ecuador vertical only. Since they were all in markets in the Andes, we found all vertical worked a lot better hand had much less multipath.
Even in the hills of Northern Lower Michigan (Delta Ground Height AMSL < About 1000 feet), V ERP only and V ERP >> H ERP seems to work well. The consensus seems to be that once the V signal reflects off the side of a hill, the polarization becomes diagonal, and it makes little difference. With LOS V only vs LOS Circular in flatter terrain, V only is noticeable by having to orient whips somewhat vertically, but still not a huge difference. I was surprised at how few problems V only had compared to Circular.
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My obvious next question is this:
The channel six in Miami ran circular polarization for good penetration into homes with rabbit-ears.
So, I can see how WAYS 50w-H signal would protect channel six's horizontal signal,
but what about WAYS's 50Kw-V signal interfering with channel six's Vertical component?
I do not know whether it is still fashionable in today's HDTV environment,
but a lot of TV stations were switching to CP a few years ago, including channel six's.
Also, since channel six in Miami is now only a virtual number, could WAYS go full circular?
The channel six in Miami ran circular polarization for good penetration into homes with rabbit-ears.
So, I can see how WAYS 50w-H signal would protect channel six's horizontal signal,
but what about WAYS's 50Kw-V signal interfering with channel six's Vertical component?
I do not know whether it is still fashionable in today's HDTV environment,
but a lot of TV stations were switching to CP a few years ago, including channel six's.
Also, since channel six in Miami is now only a virtual number, could WAYS go full circular?
I haven't followed it closely lately, but I know they still require protection in some cases. But the interference FROM the digital Channel 6s like WPVI is much worse TO the NCE FMs than the other way around, from what I've heard. Some of the Channel 6s have been very proactive over the years. Collocation eliminated the problem of the NCE FMs causing problems, but then some of the Channel 6s would get maniipulative about renting tower space. When the interference area based applications on nearby towers started showing up as a result, when reasonably priced software became available, they blew a fuse.
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Funny thing, when you read CFR 47 Section 73.525, you would think you couldn't use much power on the Channel 6 tower or close by. But if you apply all the subsections, substantially higher ERP is possible, especially with V Polarization Only and V ERP >> H ERP.
Also, in instances where there is a good working relationship with the Channel 6, there are not the continual challenges to applications and the result being many applicants give up. In some cases, it requires an in house consulting engineer to keep refiling, especially in areas like near NYC near the Grade B contours of nearby Channel 6s. Anticipating the next Channel 6 objection, and preparing the next application ahead of time was often necessary to avoid deadlines. Sometimes, the Channel 6 objections are without basis.
Also, in instances where there is a good working relationship with the Channel 6, there are not the continual challenges to applications and the result being many applicants give up. In some cases, it requires an in house consulting engineer to keep refiling, especially in areas like near NYC near the Grade B contours of nearby Channel 6s. Anticipating the next Channel 6 objection, and preparing the next application ahead of time was often necessary to avoid deadlines. Sometimes, the Channel 6 objections are without basis.
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UPDATE:
Nice day today so a little after lunchtime, I went out to an open area in the backyard with the GE Supe-2. When I got to 640, all that was there was a very weak WOI. Completely alone.
No trace of WMFN whatsoever. Three possibilities come to mind. 1.) The move to the Chicago area is imminent, and they've shut down operations in Michigan. 2.) Technical issue has forced them to cut or reduce power. 3.) Something else going on unrelated to their expected move.
Nice day today so a little after lunchtime, I went out to an open area in the backyard with the GE Supe-2. When I got to 640, all that was there was a very weak WOI. Completely alone.
No trace of WMFN whatsoever. Three possibilities come to mind. 1.) The move to the Chicago area is imminent, and they've shut down operations in Michigan. 2.) Technical issue has forced them to cut or reduce power. 3.) Something else going on unrelated to their expected move.
How high are the WMFN towers that are up? Are they all the same height that has been built?
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Thanks for the update. About 30 miles east of you I checked and found no WOI either. Unfortunately WSCR's splatter isn't helping matters.
No WOI? Did you mean WMFN? I had a very weak WOI, but no WMFN. What I've been hearing on 640 for the past several years daytime was a weak, but steady WMFN with WOI sometimes faintly underneath. More common in winter. Conditions to Iowa were pretty good today dispite some minor t-storm noise. WMT was solid. WSUI was in. And KXIC was there...very weak and mixing with something else. Presumably either CKLW or WDUX,
They were all the same height, but quite short. All the same height. I'm nowhere near your knowledge level of electrical physics, but I thought they were particularly short for 640. At the time I drove by them, I didn't know what they were. It was when I checked R-L and their map application, that I saw that the spot I had driven by was the exact location for the WMFN CP.
The other thing I'm wondering about is if these towers will ultimately rise higher, why would they be all the same height in mid-construction? Couldn't they complete each tower one at a time?
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