Milwaukee OTA HD in Chicago Metro

[AA9VI]

I'm interested in what others have seen to the south too..

I can receive these Milwaukee stations from Northbrook, IL  (comparative comments on analog signal in parenthesis)

Digitial                                  
----------------------------    
Often I get                                                    
24-1  Best  (UHF 25)         (weak analog signal)
36-1 (UHF 35)                   (weak analog signal)    
4-1 (UHF 28)                     (good analog signal)
55-1 (UHF 40)                    

rarely (20% of the time) I get
58-1 (UHF 46)          (weak analog signal)
18-1 (UHF 61)          (weak analog signal)

very rarely I get (10% of the time)
10-1 (VHF           (OK analog signal)
6-1 (UHF 33)           (weak analog signal)

next to never do I get (< 5 % of the time)
12-1 (UHF 34)    (very good analog signal, however)

in that order.  I think the 10-1 problem is due to analog adjacent channel interference from WLS channel 7 and WGN channel 9. But, I can't explain the poorer signals from the other 4 stations.  


VU-160 antenna  @ 25-30' with AP-2870 preamp (17 dB VHF, 19 dB UHF)
using DTV H20 receiver and Hitachi OTA internal TV tuner (works even better than directv)

[Nels Harvey]

Mike,
When you are receiving the Milwaukee stations from such a distance, it helps to realize there are no omni-directional patterns from most, if not all, of the stations here.  The signals are designed to basically not radiate over the lake, and, for one, Ch. 36-1 digital (Ch. 35) actually sends a reduced signal to the southeast to protect another station on the same frequency!

A common radiation pattern that some Milwaukee stations use is known as a scull pattern.  This means the signal is up, or down, in certain directions as compared to a true omni-directional pattern.  Other influences include the effect of the tower in relation to the antenna mount position.  It is pretty difficult to provide a true omni-directional pattern, and with Lake Michigan so close, it is not desirable.

I think most of the radiation patterns in Milwaukee emphasize signals to the west where the population density is pretty good, with somewhat lower signals to the north and south, especially near the lake.  I am 6 miles north of the Ch. 58-1 (Ch.46) transmitter, with an antenna mounted on my tower, line of sight, but still have problems at times picking them up!  People east of me have even more trouble.  (I am 2 miles in from the lake.)  I believe there is a significant null towards me from Ch. 58-1!

I think these are some of the reasons you notice different results in Northern Illinois.  All of this doesn't even take signal propagation into account.  I have professionally measured some of these stations signal strengths with a calibrated field meter, with an antenna 30 feet in the air and found it quite interesting to see just how much attenuation in certain directions there can be.

 I hope this helps you understand why you are getting results all over the map, so to speak.

Nels....

[Nels Harvey]

Mike,

Here are my calculations of the Milwaukee area stations signal strength in the Northbrook, IL area.  It appears you are at about 175 degrees south of most of the stations, near Capitol Drive in Milwaukee.  Ch. 49 is in SE Milwaukee County, and Ch. 55 is in Racine just west of I-94.  You are located about 67 miles from most of the stations.

These calculations were made from the FCC CDBS data, and are what is on file with the Commission.  The percentage is the amount of theoretical power in the 175 degree direction with the antenna plot data on file.  For Ch. 12 and Ch. 58 the angle changed to 174 degrees.

Ch. #      ERP      %Power in your direction

4        100KW           100%
4-1 (28)    1000KW       88.5%
6       100KW           100%
6-1 (33)     980KW        99.7%
10      223KW          100%
10-1 (   25KW         89.5%
12      316KW           97.7% (2 mi. N. Capitol Dr.)
12-1 (34)   863KW       99.6% (2 mi. N. Capitol Dr.)
18        5000KW           68.8%
18-1 (61)  850KW       90.6%
24        3020KW          78%
24-1 (25)  625KW        95.9%
36       4790KW           47.4%
36-1 (35)  500KW        69.4%
49        2570KW           24.7% (SE Milwaukee County)
55       5000KW           65.8% (Racine County)
55-1 (40)  830KW        89.7% (Actually near Capitol Dr, Milw.)
58        5000KW           99%   (2 mi. N. Capitol Dr.)
58-1 (46) 1000KW       99.6%  (2 mi. N. Capitol Dr.)

I didn’t consider the antenna heights because most of them are within 200 feet of each other, around 1100 ft, except for Ch. 49 in Oak Creek, which is only 498 ft.

Differences you are seeing there need to take the environment into consideration.  Antenna responses, coax standing waves and attenuation, and amplifier response curves on your end, plus/minus re-radiation from your area will have a factor in your reception levels.  Of course enhanced propagation at times will also change your reception.  At times the stations also may operate at reduced power for maintenance purposes.  I hope this helps you understand what you are receiving there in Northbrook.

Nels….

[Bebop]

You can use Google map to get coverage map for most the HD stations. The maps do take topography into the equation


http://www.avsforum.com/avs-vb/showthread.php?p=10127219

[Nels Harvey]

You can use Google map to get coverage map for most the HD stations. The maps do take topography into the equation


http://www.avsforum.com/avs-vb/showthread.php?p=10127219

I will play around with those topography maps when I get some time.  It looks quite interesting.  I do have suitable software to provide similar results here.

I didn't take topography into consideration when plotting the signal strengths because I think the topography between AA9VI's location and most of the TV towers will be essentially the same.  That ought to then be a non-factor theoretically.

At 60 plus miles, unless the receiving antenna is located  very high, there also are Fresnel effects to the received signal that can cause additions or subtractions to the actual signal quality, along with other environmental factors.  This will certainly vary by frequency.

Nels....

[psubill78]

I guess the bigger question is why someone in IL would *want* our Milwaukee stations

[picopir8]

Thats simple, to watch a good football team! :p

[troyriley]

I guess the bigger question is why someone in IL would *want* our Milwaukee stations

You have to remember that some parts of northern Illinois (along the state line) are actually closer to Milwaukee than Chicago.

[Sparkman87]

I guess the bigger question is why someone in IL would *want* our Milwaukee stations

I'm in N Il and my antenna is pointed to Milwaukee.  With this setup, I still get all Chicago stations except CBS-2, plus all of the Milwaukee stations.  It did get us some extra games during football season.  I was hoping to see alot of Packer losses, but i guess that only happens when they play the Bears!:D

I do get all of the Chicago nets on Comcast too, but with this setup I can pick up breaking news in Milwaukee, watch ch 18, 24, & 41 sometimes, & see the weather maps on ch 10.

[gb4fan92]

I was hoping to see alot of Packer losses, but i guess that only happens when they play the Bears!:D

Ouch that hurts!

[AA9VI]

I guess the bigger question is why someone in IL would *want* our Milwaukee stations

Well, the extra football games, March madness, channel 36 every once in a while (since I can't get channel 10 digital) and WMLW are 4 good reasons.  I occasionally tune to WTMJ (the only reliable Milwaukee news signal I can receive on digital at my house) news also since it's nice to know what's going on in other parts of the midwest .  Too bad I'm going to lose WMLW when they go to LP-D.  

As for the comparison, thanks for the input.  Yes, they are all valid points.  I wonder why not all of the UHF DT stations are putting out 1 MW.  It's hard to tell what the current status of the output power of each station is because the FCC records have old applications in there.  FYI, go to
http://www.fcc.gov/fcc-bin/tvq?state=&call=&arn=&city=&chan=&cha2=69&serv=&type=0&facid=&list=2&dist=175&dlat2=42&mlat2=7&slat2=27&dlon2=87&mlon2=47&slon2=13&size=9

and click on a station and you'll get some expired temporary and construction permits.  Anyone know what the current status of each station is?  Maybe I'm missing something.