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WMFS on STA?

P

PR680

Was reading about WDIA/WREC STA and saw that WMFS (680) was operating on one? Did I read it correctly as to why? Can't believe what I read. Could an engineer type clarify it?
 
Looks like copper theft from reading the STA.

I was actually more surprised to see there's a CP to drop from 5 to 4 towers for nighttime. Tower 5 will be dropped and a new one built nearby for daytime use only. Day power will decrease from 10 to 8 kW. I thought 680 was 50 kW.
 
I know 680 was still 10 KW in the daytime as recently as when I took their meter readings, circa 2000. When I went on my flood sightseeing tour a few weekends ago, while their site was apparently above water, street access was cut off by flood waters just south of the towers.
 
I am extremely familiar with that array, having spent many, many hours working on it back in the 80’s. The original 1940-50 era array was only 4 towers. The element closest to the building was the original daytime tower. The big tower was built to support the FM’s and as a taller daytime tower. It was a constant problem for the nighttime array. At first it was just a parasitic element, then somewhere along the way they decided to feed it with a few watts at night to make the array more stable. In the 90’s apparently they got permission to turn off the tower lights on the 4 corner towers, (I don’t see how, with Dewitt Spain just a few miles away and the runway aligned with the site).

Now they are dropping the center tower and rebuilding it? Why?

That makes no sense that I can see, unless they are going to build a taller tower for K97, and the location / design of the tower requires a drop to 8 KW.

Still…why feed it at all? Go back to using one of the nighttime elements for daytime.
 
OK. I found the application, and it makes more sense now. There are structural issues with the big tower. It’s simply a replacement, but they are NOT going to feed the new tower at night, only detune it. That’s probably a really good idea.

They’re also correcting the nominal power to match the antenna input power which is in fact 8 KW. I seem to remember now that the RMS values for a 10 KW station for that antenna only required an 8 KW input. I may be a little fuzzy on that, though. The rest of the applications looks like mostly just an administrative change / a way for consulting engineers to make money.
 
Thanks for the responses! I remember driving in one Sunday morning circa 1978-79 when the big guy had collapsed. Went out to the transmitter site after shift and it was spread all over the ground. K-97 was mono on the backup tower (5kw?) for a few months, if I remember correctly. Can't remember the exact config/power on AM until the "new" tower went up. Do remember it wasn't anything near regular service contour in daytime.

People will steal anything, but that copper could be real hot if grabbed at the wrong time of day.
 
radiosaur said:
OK. I found the application, and it makes more sense now. There are structural issues with the big tower. It’s simply a replacement, but they are NOT going to feed the new tower at night, only detune it. That’s probably a really good idea.

They’re also correcting the nominal power to match the antenna input power which is in fact 8 KW. I seem to remember now that the RMS values for a 10 KW station for that antenna only required an 8 KW input. I may be a little fuzzy on that, though. The rest of the applications looks like mostly just an administrative change / a way for consulting engineers to make money.
Click to expand...
Yes, 149 degree tall tower is more efficient than 99.5 degree tower and WMFS RMS is limited to 987 mv/m. But on the other hand, 149 degrees is not to pretty from a "Q" or band-width perspective. Driving impedance must be really high on that thing! At present night-time operation, tall tower only contributes 0.05 field ratio and is more than likely difficult to feed. Taller tower always wants to contribute more field, hard to control that low. In going away from using it at night, makes you think they may use NEC modeling of the array, negating the need for monitor point readings or being concerned with re-radiating structures and associated complex field augmentations on the license. That is much better way of doing business....

149 degrees @ 8kw vs. 99.5 degrees @ 10kw (better band-width); 987 mv is 987 mv and about the only thing that changes is the transmitter power bill.... IMHO of course!
Best regards,
w/
 
Watt, the present daytime tower has always had a bandwidth issue, to the point that waaaaay back when it was a music station, certain transient highs would dump the transmitter with a VSWR overload. I had assembled parts to try and wideband it a bit, but it never got installed.
 
Thanks for the responses! I remember driving in one Sunday morning circa 1978-79 when the big guy had collapsed. Went out to the transmitter site after shift and it was spread all over the ground. K-97 was mono on the backup tower (5kw?) for a few months, if I remember correctly. Can't remember the exact config/power on AM until the "new" tower went up. Do remember it wasn't anything near regular service contour in daytime.

People will steal anything, but that copper could be real hot if grabbed at the wrong time of day.

The tower fell in 1978. I was on the air when it happened. I took readings for the five towers, and one of them was erratically bouncing around on the meter.

I called the late Robert E. Knight, who was CE at the time. Of course, we didn't know that the tower was down, only that it was giving off some whacked-out readings. Robert went to the transmitter site and discovered the heap of metal.

You are correct that they had to temporarily hang K-97 on one of the four surviving towers.
 
Kenny, thanks for checking in! You would know the particulars on this... it seems to me that WMPS (680 AM for those who missed it back when) was just converting over to jocks taking their own readings about the time I came over from WHBQ, in late 1977. I remember Robert E. Knight was scrambling to make sure everyone had their FCC licenses. I got to visit the transmitter site on Benjestown Road just a few years ago when a friend was doing some consulting and upgrade work. With great appreciation I noted that the board, cart machines and carts were still in place from when the station was run from the transmitter on the overnight shift with Harry Simpson and "the best of WMPS". Incidentally, Kenny wrote a great piece on WMPS about the details of their "musicradio" days. If the link still works, you'll find it at boards.radio-info.com/smf/index.php?topic=72854.20;wap2

WHBQ at the time still had first class licensed engineers taking readings around the clock, with the Production Director being the licensed engineer during the workday, and the overnight readings taken at the transmitter site. On other shifts, there were engineers at the station taking the readings, and the jocks never touched the transmitter log. Years later I wound up going to church with the guy who was my engineer in the evenings, Mr. Norman Dye. Somewhere I have a copy of a newspaper ad from the era of the "Q Crew", promoting Super Walk 77. It featured a picture of the staff, programming, sales, promotions and engineering. It shows 45 employees. 45 people to run one 5 KW AM station!
 
Snazzy, I think I know what you're referring to. That is, the point where there was no requirement to have any sort of license or permit to fill out logs (which were also not required anymore). And Radeo, you are referring to the point where the "class" system of licenses was dropped altogether, replacing the 1st, 2nd, and 3rd tickets with "restricted radiotelephone permits" which one sent a postcard in to obtain instead of taking a test, and General Radiotelephone Operator Licenses which did require passing a test. I am familiar with that era in the early 80's, because I was studying to take the second and first class tests when they did away with them altogether. The GROL replaced the first and second class licenses. The GROL's are still in existence, I took the test and got mine in 2008. It has no real value in broadcasting, but is mostly for marine, aviation, and two-way radio engineering. You need one to work on communications transmitters, but there is no license requirement to work on broadcast transmitters anymore.
 
I didn’t need a GROL to work on WMC-FM’s 300 KW ERP transmission system, but I now need one to work on the 2.5 watt transmitter at Millington airport. Go figure.
 
I recall I still had to get a 3rd class permit in 1978. (WTPR-Paris, TN) but before my three months (or whatever the time was) the rules changed and I DID NOT have to go to Nashville and take a test. We filled out some forms and they sent me a 3rd class operator's permit. I still have it somewhere.

Is there anything required today at all?
 
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