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FCC grants WBBM a CP to move transmitter site

My SIL lives near the WTMJ towers and near where the new Foxconn factories are being built. When we have stayed there, I listened to WBBM quite a bit and the signal was wall to wall. But I also was also able to hear WSGW there in the Daytime by nulling out WBBM before IBOC.
 
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My SIL lives near the WTMJ towers ... But I also was also able to hear WSGW there in the Daytime by nulling out WBBM before IBOC.

Below is a calculation of the daytime field intensity of WSGW near the WTMJ tx site...
WSGW-Daytime-F-I-WTMJ-Tx-Site.jpg
 
In other words, the indirect method measures power at the transmitter times its efficiency whereas the direct method measures it at the base of the antenna.
I could be wrong, but I believe that the direct method can also measure power at the common point (input) of a phasor.

I always thought that the indirect method referred to a remote control operation, where readings are taken at a separate studio instead of the transmitter site. Is that wrong?
 
I always thought that the indirect method referred to a remote control operation, where readings are taken at a separate studio instead of the transmitter site. Is that wrong?

It is - this is purely about calculating the power output of an AM station, regardless of where the studio is.
 
Thank you! I only had that one wrong for about 45 years. Actually, I don't remember hearing the term prior to 30 years ago or so.
And yet, it's shown on many History Cards from the early days of radio!

Bird Wattmeters have been around for 77 years!

https://www.birdrf.com/Products/Test%20and%20Measurement/RF-Power-Meters/Wattmeters-Line-Sections/RF-Wattmeters.aspx
 
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Thanks for that WSGW calculation, rfry. They are actually a few miles East of WTMJ, near I-94, but West of the Foxconn construction. You can see WTMJ's and WISN's tower lights at Night. It's a mess there, with constantly changing plans, and widening roads. They've even created a new town, called Mount Pleasant. We were driving one day down a road with what looked like a High School, but there were guard towers around it, and fences with concertina wire. I asked my in laws about it, and they said it had been converted from a HS to a correctional facility. I said maybe it would be a good idea to put guard towers and fences around some High Schools. There's a nearby town with an area of houses built from Quonset Huts. I guess it had been a military installation at one time. The TV antennas are interesting there, area specials with lobes toward both Milwaukee and Chicago. The poster from Kenosha who posts here and other radio boards probably can tell us what's going on also.
 
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There's a nearby town with an area of houses built from Quonset Huts. I guess it had been a military installation at one time. The TV antennas are interesting there, area specials with lobes toward both Milwaukee and Chicago. The poster from Kenosha who posts here and other radio boards probably can tell us what's going on also.

The town with what used to be military quonset huts sounds like what used to be the Bong Air Force base. Most of their land was unused and is now a state recreation area. (Yes, the state of Wisconsin is home to the Bong Recreation area). As for those TV antennas, the area between Racine and the Illinois state line (about 20 miles) is a zone where Chicago and Milwaukee TV signals are easily receivable.

Back in the days before cable and satellite, antenna rotors were a big business in the area, I even had a rotor on our first house here in Crystal Lake. All but the low powered stations from both cities were readily available on a daily basis.
 
In 60068, I saw WTMJ-TV 4 on occasion on Tropo with Rabbit Ears. There's the 72-76 MHz Buffer. I think 6, 10, and 12 were overwhelmed with adjacent channel interference from Chicago stations. I'm sure they could have been seen with a Top Of The Line TV antenna on a Rotator.
 
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Reports are that the old WBBM tower in Itasca, Illinois is coming down this Wednesday or Thursday depending on weather conditions.
 
It certainly did. Nice video

I must admit to a certain amount of nostalgic sadness about a nearly 80 year old tower going horizontal.
 


I must admit to a certain amount of nostalgic sadness about a nearly 80 year old tower going horizontal.

Understandable. I feel twinge of that myself. But the consolation....at least from my "small sample size" experience, including my road trip last week...is that WBBM seems to be doing just fine from its new perch with WSCR.

And then there's WLS with it's 81-year old stick.
 
Sad to see the tower go down. For 25 years I used to drive past the tower every day going to work. I would enter I-290 at Thorndale and the first thing that I would stare at was the WBBM stick followed shortly by the WGN stick.

Here is a nice article from Scott Fybush about the now ex-WBBM site: https://www.fybush.com/site-20190614/
 
The new tower and signal haven't seemed to affect my reception of WBBM in eastern Iowa, day or night, which is important to me since it's actually an AM station that I rely on. Although the daytime signal has never been as strong as I would like.
 
Well, it IS closer to Iowa. But further from the Lake Michigan Shoreline, where the highest population concentration tends to be. Also, further from the high end Chicago mover and shaker retreats in SW Michigan, along the Lake. And with lower Inverse Field. I wonder if they measured the radials, they could at least bump the Day power up a little. They have already done that with WCPT 820 and WCGO 1590. WCGO is up to 10000 watts now. Some skirting arrangement to shorten the electrical height would also allow them to use more power with less fading from the vertical minor lobe self interference. WBBM has a 10000 watt AUX on one of the 1240 towers, the one not used for WCPT 820 obviously. It's looks to be the WSBC tower on Belmont? Or maybe the WXRT AUX tower, if it's a different tower?
 
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Yes it's the old WSBC tower on Belmont Avenue. WBBM AM and WSCR have a CP to use this tower as AUX with 10kW. They both filed a Licence to Cover with FCC for those CPs. The same tower is also used as AUX for following FM stations: WBBM FM, WXRT, WCFS, WUSN and WBMX.
 
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