Wbbm Cbs 2 Chicago

[dodge]

Wbbm Cbs 2 Chicago

 

[dougruss]

Wbbm Cbs 2 Chicago

You got that Right !!

 

[erosslacm]

Indeed

WTF! What is wrong wbbm? I thought VHF signals traveled farther and UHF signals, what can it be, cheap transmitter?

 

[dodge]

WBBM DT 3 Sucks

Part of the problem is the A##holes at WBBM are Cheap and they are only pushing 4.4 kw out of their transmitter. The station Engineers there are also a bunch of morons and dont understand why everyone has prblems with their ota reception. Most other Chi-Town Stations are pushing like 20 kw. The other Problem they are on the Hand-Cock Building which is lower than the S tower that all other Tv Transmitters are on. The third problem is VHF Tv is Very Susceptible to EMI Interferance and Propagation on Vhf is very goofy.

 

[rad]

Part of the problem is the A##holes at WBBM are Cheap and they are only pushing 4.4 kw out of their transmitter. The station Engineers there are also a bunch of morons and dont understand why everyone has prblems with their ota reception. Most other Chi-Town Stations are pushing like 20 kw. The other Problem they are on the Hand-Cock Building which is lower than the S tower that all other Tv Transmitters are on. The third problem is VHF Tv is Very Susceptible to EMI Interferance and Propagation on Vhf is very goofy.

I believe that it's the FCC that's limiting how much power the can put out. IIRC, when they installed the new digital antenna a couple of years back they also needed to get approval from the Canadian version of the FCC for what they could use. Also, in general, ATSC stations do put out less power then their NTSC equivlant. Look at WCIU-TV on 26 puts out 5000KW, WCIU-Dt on 26 puts out 160KW or WFLD-TV on 32 puts out 5000KW while WFLD-DT on 31 puts out 690KW.

Face it, low band VHF just sucks for a number of reasons.

 

[Tower Guy]

WTF! What is wrong wbbm? I thought VHF signals traveled farther and UHF signals, what can it be, cheap transmitter?

Cheap antenna at your house?

 

[dougruss]

Cheap antenna at your house?

Nope !! It's a Big problem for alot of us in this Area !

 

[Rick0725]

a big problem with ch 3 requires a big antenna.

this can be accomplished with the "heavy hitters" with high low band vhf gain

like the winegard hd 7082p, hd7084p, hd 8200p

or combine a tuned ch 3 vhf antenna with a ch 3 jointenna into your current setup.

or a ch 2-6 vhf antenna

or a ch 2-13 chf antenna

whats holding you back?

Do you want cbs hd bad enough.

 

[Barry Erick]

The third problem is VHF Tv is Very Susceptible to EMI Interferance and Propagation on Vhf is very goofy.

Mostly the lower VHF band. And they are in the low band, it looks like. Well, the e Fcc is mainly staying at and above ch 7 for a couple of reasons. WBBM is probably waiting to switch to their main analog channel when analog shuts down in'09. It is hard to justify a cap purchase for 2 years if the analog transmitter is still on the books and can be modified.

Also, due to how analog and diigital power is measured and the modulation process, it takes much less power to put out an equivalent footprint of the analog signal.

And the total powe is ERP, and not transmitter power. In digital, we tend to look at xmtr power and in analog, to ERP, or Effective Radiated Power - the power in the focused beam of the antenna. Gain because the signal is not sent up into space or down into earth, it is concentrated to the population. For instance, one of our UHF Analog transmitters is 110kw with an ERP of 3.8 megawatts and the equivalent Digital VHF transmiiter is 6kw with an ERP of 30kw and the footprint exceeds our analog by lots.

 

[dodge]

I have a Winegard HD 8200p with the AP8275 preamp and still only get it 50% of the time, antenna is on 2nd story roof on a 15' mast.

 

[Tower Guy]

Nope !! It's a Big problem for alot of us in this Area !

I have noticed that many posters with WBBM problems have installed the wrong antenna.

 

[Rick0725]

Besides selecting the correct antenna, another area to explore is amplification.

vhf vs uhf

wbbm is low power compared to the other vhf monsters in the area collecting at the antenna. selecting the appropriate amplifier can be a factor.

-try amplifying uhf only and passing vhf.

-separate the vhf and uhf signals off the combo antenna with a cm0549...either pass vhf or use a separate amp of less gain and better overload tolerance to amplify vhf then recombine the vhf and amplified uhf signals with another cm0549.

this has been my workaround in the binghamton, ny area. the digitals are on ch 4,7,8 at very low power, (around 2000 watts) with a very dominant ch 12 analog which wrecks havoc throught the tv band (along with the 50-100 kw fm towers in the area).

I have even used vhf and/or fm band stop filters (available locally) to attenuate the vhf/fm before the uhf signal is amplified to assist.

all these measures improved overall system performance. I even do that at my home. in my case I amplify uhf only with a winegard hdp 269 and pass vhf. It helped receive the lower power stations in the area and at the same time gave the uhf a boost with less interfering issues.

 

[dodge]

no amp

I had no amp when I first put the antenna up, and had no wbbm at all and was very very disappointed as it was the biggest VHF antenna I could find. After I put the amp in I get can wbbm but it will go watachable for 30 minutes, pixleate a few times then I will lose signal for a few seconds and come back, it is really irriatating. During the day I can barely watch it at all after 6 pm. it gets better.

I kinda think I am in a Signal hole here, my brother is a few miles north of me and has and old winegard 7084 that was hit by lightning that I pulled out of a dumpster , I replaced the terminal board and it was good to go again. It fell over a few times and the delta wings are completely gone, one of the rear long vhf elements is missing and few have been bent and restraightend. And that old beater performs better than my brand new antenna. And it is only up about 18 feet.....

 

[Tower Guy]

I get can wbbm but it will go watachable for 30 minutes, pixleate a few times then I will lose signal for a few seconds and come back, it is really irriatating. During the day I can barely watch it at all after 6 pm. it gets better.

You are describing interference from another channel 3. The time of day and frequency of the interference sounds like meteor scatter propagation. The short duration and time between disturbances is exactly the frequency of random meteors. Meteor scatter peaks at 6 AM (7 AM DST) and minimizes at 6 PM (7 PM DST). The station that is most likely to interfere may be 800 miles away. Due to your antenna orientation, WCAX in Vermont, WSYR in Syracuse, NY, and WFSB in Hartford, CT are possible candidates.

If you want to prove interference from meteors, turn an analog TV to analog channel 4 during the early morning. See if one or more brief signals (.5-3 seconds) appear at the same time that WBBM-DT breaks up.

If you do this on April 22nd, you'll have a greater chance to observe the problem. That's the date of the next meteor shower.

http://en.wikipedia.org/wiki/E-skip#Meteor_scatter_propagation