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WIBG's Nitetime Signal in the Mid-70's

Does anyone remember Steve Naijt, who was brought in from Fairbanks Broadcasting to install new equipment, to improve their nitetime signal. I remember visiting their, and talking to one of the chief engineers--Les(forgot his last name)--he was jokingly saying that, "the signal could be heard all the way to the Bahamas". Also. I remember Steve Hatley refering to it as, "the 50,000 watt flower pot". Does anyone know the whereabouts of Steve? Also, Mark Surpass, who was MD for Kevin Metheney at WZZD?
 
Unfortunately, Steve Hnat passed away several years ago. When I arrived as CE of WZZD in 1981, pretty much all of the audio processing gear in use was designed and built by Steve. Each cart machine had its own compressor/limiter between the machine and the board. All were built by Steve and his crew (WZZD had a full-time IBEW union engineering staff until 1984). The transmitters were fed by tri-band limiters that Steve also designed.

Even the mic preamps, distribution, headphone, and monitor amps were locally designed and built. Believe it or not, a few of the distribution and monitor amps are still in use at WNTP/WFIL today. And they still work flawlessly. That alone will tell you how good a design engineer Steve was.

In 1983 I rebuilt the studios and removed a lot of the audio processing gear he had installed (like the cart machine compressors). When we installed a new Harris MW50 transmitter in 1984, and retired the old Wibbage RCA BTA50G, we removed the last vestages of Steve's audio processing from regular service, and installed an Optimod 9000 audio processor on the MW50. We did keep one of the multiband processors for use on the 10kw auxiliary transmitter, but it rarely saw any on-air time.

I left WZZD in 1985 and when I returned in 2004, except for the da's and monitor amps I mentioned, all Steve Hnat gear was gone. I assume that most of it was removed when the WZZD-WFIL consolidation took place in the mid-90s.

By the way, about that night pattern: The pattern was cigar shaped with the towers at one end. The signal was beamed directly towards Philly and south Jersey. The pattern was so tight that with 10kw (actually it was 6.5kw -- but that's another story) the main lobe was actually equivalent to 40kw. Of course, you could barely hear the station at the junction of the turnpike and northeast extension in Plymouth Meeting - about two miles west off the transmitter. In 1984 we began doing studies to let out the night pattern. We were able to do this because of changes in international radio law, which did not force the station to give as much protection to CBW in Winnepeg as the old laws. That project was completed in 1986. WNTP still uses the same night pattern today.
 
You mentioned Steve Hatley and Mark Surpass. Sadly, Steve Hatley died in a motorcycle accident. Mark Surpass moved to New Orleans. I worked for the staton in the late 70's under Steve Hnat.

Carl L.
 
rtetro said:
By the way, about that night pattern: The pattern was cigar shaped with the towers at one end. The signal was beamed directly towards Philly and south Jersey. The pattern was so tight that with 10kw (actually it was 6.5kw -- but that's another story) the main lobe was actually equivalent to 40kw.

I think it's time for the other story. ;)
 
I knew Steve and Mark personally when they worked at WZZD. I knew about his passing--I believe it happened a year or two after he left Philly, while he was working in Oklahoma City. Also, I know that Bill Winters died from a heart attack at age 35 and John Wesley Harding committed suicide sometime after he left WIBG.
 
oldiesfan6479 said:
I think it's time for the other story. ;)

Back in the day, the FCC would only allow standard power levels .10kw, .25kw, .50kw, 1kw, 5kw, 10kw, and 50kw. (Later on they added 2.5kw and 25kw, and eliminated .10kw.) You were not allowed to license intermediate power levels like 1.4kw, 12.7kw, and so on. When the night pattern for WIBG was being designed it was found that the station could easily do 5kw and meet the allowed signal parameters. But 10kw would have exceeded the pattern limits. Some further study showed that the maximum they could get and still meet the pattern requirements was 6.5kw. So what they did was apply for the 10kw power level and use a large resistive network (similar to a dummy load) at the input to the phasor to reduce the power by 4.5kw. I remember the resistor network looked like several toaster elements connected together in series and parallel. Pretty ingenious. And as I remember, it kept the phasor room pretty warm at night, too.

So, by a little technical trickery, WIBG was licensed at 10kw: The transmitter put out the required 10kw, but the second the signal hit the phasor 4.5kw went up in heat. And, in reality WIBG only broadcast at 6.5kw at night. When the day and night patterns were reworked in the mid-80s, the new night pattern allowed the station (by then WZZD) to go to a full 10kw, as well as eliminating one of the original five towers.
 
rtetro said:
Some further study showed that the maximum they could get and still meet the pattern requirements was 6.5kw. So what they did was apply for the 10kw power level and use a large resistive network (similar to a dummy load) at the input to the phasor to reduce the power by 4.5kw.

Rene', I think you mean 3.5 kW--10-6.5=3.5 and 3.5 makes more sense. Back in those days, Class II AMs, such as WIBG, had to produce an RMS field of 175 mV/m/kW @ 1 mile. To get that efficiency after losing 35% of the power in the resistor network required a real efficiency of 217 mV/m/kW @ 1 mile. That was almost Class I efficiency. Normally you'd need towers of about 150 degrees to achieve that. I don't think the WIBG towers were that tall, but some patterns have a salutary effect on efficiency; the vertical radiation pattern is "squished" producing higher efficiency than you would normally expect. WIBG could have had such a pattern. Also, the FCC used to give directional stations special dispensation to miss the minimum efficiency by, IIRC, 5%. I suspect that when the WIBG facilities were built, standard patterns were not yet in use; the old MEOV (maximum effective operating values) system was still in use and that was the system under which the FCC allowed the 5% efficiency misses.

By now, most--but hardly all--stations in such situations have abandoned the antenna-current limiting resistors. The most famous case that still exists is probably KOA, which as a Class A is required to run 50 kW and to produce a field of at least 362.2 mV/m/kW @ 1 km. However, KOA's tower is 207 degrees, I believe, so its efficiency is more than 400 mV/m/kW @ 1km and KOA is limited by US-Mexico treaty to a field of 362.2 mV/m/kW @ 1 km at night. This crazy situation (the field must be exactly 362.2 mV/m/kW @ 1 km--no more and no less) forces KOA to run 50 kW and to use a current-limiting resistor to waste approximately 10 kW of transmitter-output power. I have never figured out why KOA does not short out the resistor or network during the daytime, when the higher efficiency should not be a problem.
 
Interesting Topic. I was wondering which of the original 5 towers was used for WIBG FM and later WPNA. I believe it was 94.1 FM. Does anybody remember when it was moved to become WYSP?
 
athegymtday said:
Interesting Topic. I was wondering which of the original 5 towers was used for WIBG FM and later WPNA. I believe it was 94.1 FM. Does anybody remember when it was moved to become WYSP?

Not sure when the move was made, but WIBG-FM was on tower 3 - the center tower of the array. Up until the WFIL-WZZD consolidation the old tuning house type structure which housed the isolation coil for 94.1 remained at the tower base. The concrete pad is still there. I also have one of the old horizontal FM bays in the radio station basement....makes and interesting piece of memorabilia.

Note to Dan....
Thanks for correcting my math. You're right that it should be 3.5kw. Seems the older I get the less math I can do on the fly in my head....i guess even the simple stuff. :)

The tower height of all the towers are (and were) about 90 degrees (89.1, if my memory is correct). I would have to go back and look at the original proofs to see exactly what the RMS was in those days. If I get a few moments tomorrow, I'll run down in the basement and check the old engineering files.

I would suspect that the 'special dispensation' for missing the efficiency minimums may very well have come into play. With the patterns being so tight, thus creating incredible fields in the main lobes over the city of license, it may have been allowed. Again, I would have to look it up, but I believe the effective power in the daytime main lobe was somewhere around 200kw.

Always great to hear from you Dan. I have always appreciated your input on the various sites where our paths have crossed.
 
Rene, I posted some questions to you on Saturday morning about WNTP. I posted it on the wrong forum--it was posted on the "Philly radio in the early 70's" topic. Sorry for the mistake.

"Super Jock"
 
I remember the nitetime signal during the beatle era 64-66, it was almost impossible in the south philadelphia area to pick them up clear, WABC was the alternative. When they switched to 10kw-n (dont know if they used the 5 towers at night), with their strict directional nitetime pattern anything south of center city was out of luck. It was hard to understand how a full powered philadelphia licensed signal could be so bad at night. Daytime they were gangbusters, when WFIL started rocking in 66 their nitetime signal was just the opposite 5kw beaming southeast and very stong all the way to the coast.... sort of like WAMS 5kw of wasted power going down the river and bay, and now 1380 is receivable in philly on a piggyback WILM tower with much less power....go figure.
 
One thing we have not talked about in this thread is the changes in radio propagation between 60s and today. Back in the 60s and early 70s there were really only three stations of consequence on 990 at night in the eastern half of the continent: CBW in Winnipeg, WNOX in Knoxville, and WIBG. Everyone else on present day 990 was either a daytimer or non-existent. For example WDCX 990 in Rochester did not come on until the 80s and CKGM in Montreal didn't move from 980 to 990 until later. So the amount of interference to 990 in Philly at night was much less severe than it is now. Most of the skywave then came from WNOX.

Now just about every mom and pop station has some small amount of nighttime power, even if it's only just a few watts like WNTW; plus, of course, the higher power night stations like WALE, CKGM, and WDCX. WLEE near Richmond just added subtantial night power last year.

Technically, all of these newer stations are supposed to protect WNTP. And, if you look at their patterns on paper (or online) they do. However, in practice it's a much different story. WNTP receives a lot of co-channel interference from both CKGM and WDCX at night. These are my two biggest problem stations. Most nights in the colder months CKGM can be clearly heard under WNTP even within our protected nighttime contour (7.14 mV/m).

All of that being said, if WNTP were to try to increase their nighttime power or loosen its pattern, not only would we have to consider WNOX and CBW in the study, but all of the other nighttime stations that have subsequently come on the air. It is a very tight box. Most of what signal improvements would be made would be seen in New Jersey and northern Delaware because most other directions are pretty much boxed in. It's been talked about for years, going back to Wibbage. In today's world the only thing holding back higher power at night are those surrounding stations. We can dump 50kw towards the Atlantic Ocean, such as WALE does, but holding back the signal in other directions is going to be VERY, VERY tight. Increasing WNTP's power to some level higher than 10kw more than likely can be done, but it will almost assuredly require moving the night array to the west, similar to the move that WPEN made a few years back. Back in the WIBBAGE days the technology of directional antennas just wasn't there yet to allow higher power at night for WIBG than 10kw.

WFIL's pattern is a different story. It is much less restrictive at night than WNTP, although it is still like WNTP, generally beamed southeast. WFIL actually puts much more signal over Philly and south Jersey at night than during the day because the signal at night is sucked in to the northwest at night. Directional antennas are like a balloon. If you squeeze them in one direction, the signals are going to bulge out somewhere else. The pattern at the present WIFL transmitter site is pretty much what it was at the old site on Franklin Way. There were really no major modifications to the pattern when it was diplexed with 990.
 
Rene, thanks for the detailed info about WNTP's night signal. I remember in the 70's, not only being able to hear WCFL, but occasionally WRC and CKGM at night.
 
rtetro said:
WNTP receives a lot of co-channel interference from both CKGM and WDCX at night. These are my two biggest problem stations. Most nights in the colder months CKGM can be clearly heard under WNTP even within our protected nighttime contour (7.14 mV/m).

Highly directional Canadian AMs that violate the terms of their licenses are no rarity. I would not be surprised if you were able to demonstrate that the Montreal 990's night operation was out of spec.

As for Rochester, great story about how they came to be on 990. They were, in effect, chased off of 680 by CFTR. There are probably similar stories about a few other North America AMs but I don't know those stories.
 
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