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I'm seeing something new on WQDI 20.3 where Cheddar used to be. The bug is too small to read, but it looks like some sports network. Looks like Bein Sports. It's not being carried on KONV .3, however.
 

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There's nuance to this that gets lost on a lot of people because a lot of the details are so obscured by the passage of time. UHF stations are allowed 1000 kW, yes, but that power level was designed in an attempt to allow for UHF digital facilities to match VHF analogs, which had much larger coverage than UHF analogs.

Originally, the rules only allowed UHF analog stations to boost power up to 200 kW on digital, as that was considered to be roughly equivalent to analog UHF in most cases. So rather than 20%, the comparison is actually 4%. Many UHF analog stations were actually assigned digital power levels below 200 kW, with a floor of 50 kW used to allow stations to expand if they so chose. To that point, WEWS needed at least 1000 kW on 15 to match its 93.3 kW analog channel 5 signal, but WVIZ needed only 66.9 kW on channel 26 to match its 2140 kW analog on channel 25. (Source: FCC Order 98-315 - DTV Channel Allotments - Ohio )

When viewed through that lens, 4% of 236 kW (which I found to be WJW's analog power) is 9.44 kW. That's actually less than the 11 kW they use today.

If you're wondering, the rule was eventually changed when the FCC was convinced that there was no reason to artificially restrain the power of stations that were UHF on analog rather than VHF, but that just implies that the extra power for those stations led to an expansion of coverage, rather than a match to the UHF stations' existing analog coverage.

- Trip

EDIT: Decided to check WJW's analog power and found it was 236 kW. Adjusted that paragraph accordingly.
That makes sense.

By the way, didn’t you mention that when you worked for WDBJ, they had an issue with VSWR at one time and didn’t get out as well as they should have? I wonder if this may be an issue with some stations.
 

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The big problem WDBJ had at the time was that the exciter was manually-corrected, so the SNR out of the transmitter was rarely above 29 dB. It had to be corrected again every few weeks as conditions changed and it would drift lower. The lower your SNR out of the transmitter, the less range you have, generally. They've since replaced their exciters with a self-correcting model and now regularly make 36 dB easily.

- Trip
 

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The big problem WDBJ had at the time was that the exciter was manually-corrected, so the SNR out of the transmitter was rarely above 29 dB. It had to be corrected again every few weeks as conditions changed and it would drift lower. The lower your SNR out of the transmitter, the less range you have, generally. They've since replaced their exciters with a self-correcting model and now regularly make 36 dB easily.

- Trip
I mentioned that about WVIZ's old frequency, which I believe was when you originally commented about that station. No matter how good your reception was, WVIZ never seemed to make it over 27 dB. They easliy reach 36 dB on their repacked frequency, of course the new modern transmitter made that possible.

The engineer at WEWS told be back in 2018 that they were doing some transmitter maintenance on their main transmitter, which when it was brought back online, provided better reception on my end. So I think they replaced their transmitter with a solid state one, even though they were not affected by the repack.

Most of the repacked stations do provide a better SNR because of modern transmitters and exciters. I'm sure WOIO is still using an IOT, so once they sign on from the former WUAB tower, I would expect to see a much higher SNR from them with a modern transmitter along with the 20 kW of ERP. I predict that they will be on par or slightly better than WJW, which comes in for me with a SNR of 35-36 dB.
 

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I'm sure WOIO is still using an IOT, so once they sign on from the former WUAB tower, I would expect to see a much higher SNR from them with a modern transmitter along with the 20 kW of ERP.
Any idea when 19/43 will be moving to the former WUAB tower?
 

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Any idea when 19/43 will be moving to the former WUAB tower?
All I know is that they currently have an approved construction permit. I don't know when they will begin work or when they will sign on from the new location.

Perhaps someone can reach out to an engineer for more details?
 

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I'm sure WOIO is still using an IOT
IOTs were primarily used by UHF stations. Solid state technology has been sufficient for VHF power levels for a long time. I would be extremely surprised if WOIO used an IOT.

- Trip
 

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Yeah, that's why I said most. If electrical interference isn't the problem, it's interference from other broadcasters. I personally never had much of an issue with WOIO, even when it was beaming out a whopping 3.5 kW of power. But then again, I've been using a proper UHF/VHF outdoor antenna, which I understand isn't an option for everyone. Very rarely have I experienced a degraded signal from co-channel interference, which is a problem for many VHF stations, no matter how close you are to the tower.

Even though it's now on the low VHF band, it appears that WGGN has been reaching distant areas very well with a proper antenna, and I've been able to catch it a few times myself with a little bit of tropo. They probably have a good transmitter that produces a good SNR. I'm sure when WOIO moves, they will be using a newer solid state transmitter, which will likely boost my SNR of them from 31 dB up to 35-36 dB. Low power VHF stations are especially the ones that are problematic, and WCDN-LD which is about 18 miles away from me, is either a semi-decode or non-existent, even though it reaches me somewhat well. There are even a lot of viewers in Detroit that have issues with WHNE-LD after they were repacked to RF 3, even in suburban areas with a proper lo VHF outdoor antenna. WOIO's RF 10 looks encouraging though, and we'll just have to wait for viewer reports once they sign-on with their improved broadcast.
Agreed. I've found since the repack that VHF seems to be more reliable (as the slightest bit of tropo causes interference to the now-packed-like-sardines UHF signals). Even powerhouses like WKYC and WBNX are affected at times (and they never were before the repack). The only UHF that has improved since the repack is WEAO (getting it away from being co-channel with Erie's PBS and I suspect the lower frequency gets through the trees/over the ridge better).

WOIO and WJW are always 31-32 dB, and even WGGN is surprisingly good (even though their transmitter is in the opposite direction from where my antenna is pointed) and is MUCH more reliable on RF3 than it ever was on RF42.

However, I do have an outdoor antenna and live in a fairly rural area without much electrical interference except for thunderstorms.
 

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Agreed. I've found since the repack that VHF seems to be more reliable (as the slightest bit of tropo causes interference to the now-packed-like-sardines UHF signals). Even powerhouses like WKYC and WBNX are affected at times (and they never were before the repack). The only UHF that has improved since the repack is WEAO (getting it away from being co-channel with Erie's PBS and I suspect the lower frequency gets through the trees/over the ridge better).

WOIO and WJW are always 31-32 dB, and even WGGN is surprisingly good (even though their transmitter is in the opposite direction from where my antenna is pointed) and is MUCH more reliable on RF3 than it ever was on RF42.

However, I do have an outdoor antenna and live in a fairly rural area without much electrical interference except for thunderstorms.
Yeah, I'm really impressed with WGGN on RF 3 now. I am 43 miles from the transmitter, and they're a solid 90% SNR here. I could not receive them at all on RF 42. Even strong tropo had a difficult time bringing UHF WGGN here, which leads me to think there were problems with them on UHF.

I lost WOUC in the repack when it moved from RF 35 to 6, but RF 6 is probably the worst channel ever.
 

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In general, the noise floor issues are worse the lower the RF number.

RF 6's more unique issues are caused by the occasional pirate operating on 87.7-87.9 (along with some car FM adapters where people mistakenly set it to a frequency below 88.1 because they think it's safe when they hear nothing but snow) and the slightest boost from franken FM stations that are focusing most of their power on the audio carrier instead of the video carrier to extend their reach. (i.e. WLFM-LP up until this past summer). And it doesn't help that many FM traps designed to block the entire FM band also cutoff a portion of RF 6.

The difference with WOUC is that they have a directional 7.11 kW that's using a pattern similar to the one they've had ever since they were on analog 44, compared to the non-directional 10 kW signal that WGGN has on RF 3. Many longtime RF 6 stations have since increased their power to 30 kW+ power levels, but WOUC currently has no pending applications for an increase.
 

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In general, the noise floor issues are worse the lower the RF number.

RF 6's more unique issues are caused by the occasional pirate operating on 87.7-87.9 (along with some car FM adapters where people mistakenly set it to a frequency below 88.1 because they think it's safe when they hear nothing but snow) and the slightest boost from franken FM stations that are focusing most of their power on the audio carrier instead of the video carrier to extend their reach. (i.e. WLFM-LP up until this past summer). And it doesn't help that many FM traps designed to block the entire FM band also cutoff a portion of RF 6.

The difference with WOUC is that they have a directional 7.11 kW that's using a pattern similar to the one they've had ever since they were on analog 44, compared to the non-directional 10 kW signal that WGGN has on RF 3. Many longtime RF 6 stations have since increased their power to 30 kW+ power levels, but WOUC currently has no pending applications for an increase.
WOUC is not as robust as it should be. During the repack, I believe they lowered their antenna height by about 100', so that didn't help. But I think my main problem is just FM broadcast interference. Those towers are about a mile or two from my house, and it's impossible to filter all of them out without also filtering channel 6. I think there may be intermod or just generally a high noise floor caused by them. The fact that I have an 88.1 so close to my home doesn't help.
 

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WOUC is not as robust as it should be. During the repack, I believe they lowered their antenna height by about 100', so that didn't help. But I think my main problem is just FM broadcast interference. Those towers are about a mile or two from my house, and it's impossible to filter all of them out without also filtering channel 6. I think there may be intermod or just generally a high noise floor caused by them. The fact that I have an 88.1 so close to my home doesn't help.
You should be aware that WOUC has been having issues such that local viewers are getting pixelization even when the signals are 100% strength, 90%+ sig quality and 100% symbol quality. One of my friends has actually called into the station to make them aware of the problem, but it has been popping up again intermittently. The University which runs the TV and FM stations has some financial issues despite the fact that they received $14 million or so for moving from RF35 to RF6. Bottom line, their signal isn't the best right now so it may not be your local RF environment.
 

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That probably wouldn't surprise me, seeing that WIVM is practically a rim shot for the WIVX transmitter. Didn't you say that the WOIO repeater is setup in the same manner? I wonder how that will work out when WOHZ-CD starts repeating WOIO/WUAB? They're going have to use a microwave link or something as both RF 10 & 18 will pretty much be impossible to receive at their new transmitter location.
Why will receiving RF10 be impossible at the new transmitter location? At least on route 95 in southwest Wayne county I see outdoor tv towers which are pointed to Cleveland? Do you have a rabbitears analysis of the area or other info so I can see why it is not feasible for WOIO to simply receive WOIO.

Last summer I e-mailed an engineer of a western Ohio tv station, he stated that a person in Wyandot county was able to receive WJW and WLIO by simply turning their antenna in the direction of the towers. He stated that a good VHF antenna was necessary.
 

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You should be aware that WOUC has been having issues such that local viewers are getting pixelization even when the signals are 100% strength, 90%+ sig quality and 100% symbol quality. One of my friends has actually called into the station to make them aware of the problem, but it has been popping up again intermittently. The University which runs the TV and FM stations has some financial issues despite the fact that they received $14 million or so for moving from RF35 to RF6. Bottom line, their signal isn't the best right now so it may not be your local RF environment.
This is quite interesting. Here in Rittman I can sometimes see the hump over about 6-10 dbfs over the noise floor with RTl-SDR and still sometimes the signal does not decode.

How bad are the financial issues?
 

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This tv antenna is used for FM radio and dtv

I intend to increase my antenna height from 15 ft to 45 or 50 feet.
I will give FM fool and rabbitears results for the three secenarios
FM
15 ft.
3120971
3120973
3120975


Rabbitears reports
15 ft.
RabbitEars.Info

45 ftRabbitEars.Info
50 ft
RabbitEars.Info

Currently I am having continuous reception issues with WOUC. I used to get reception for four hours almost daily using a radioshack vu-190 but when I switch to a HD200XL all reception is dropped and the signal meter bounces back and forth.

I also have reception issues with WYFX. During the winter I received this well mostly throughout the day. However as soon as the temperature outdoors increases to 40 degrees the reception discontinues. Also when I try to readjust my secondary amplifier settings I notice this can kill the WYFX more liberally in warmer weather. This suggests to me that there is tropospheric enhancement which is contributing to a decrease of a dynamic range of my tuner.

My thoughts are that attenuating channel 31 and 33 is not sensible because these signals are not very strong so it would never cause issues with WYFX. However, I see tropospheric duction as sort of enlarging the coverage area of a transmitter and thus can raise signals several db although I do not know how much so in practice.

If I am not mistaken the signal levels of RF 22 and 24 are not far from overload territory but will everyday northeast Ohio tropo really bring the signal levels to such a degree as would ruin reception of WYFX and WOUC.

If I use two attenuators for channel 22 and 24 that have a 25 db attenuation level with an insertion loss of 2 db, can I drastically cut distortion to weak signals assuming such distortion exists?
Could I do this just as effectively with a 2db attenuator before the preamp.
?

Or is overload unlikely and there are other issues that I need to work on or simply raise the antenna to get around trees etc?

Background info and Observations:

I live on the outskirts of a small town wherein the population density is about 200 people per sq mile. With my outdoor antenna I see little noise in horizontal polarization although I do know that in vertical polarization there is some noise up to about 54 MHz outdoors that seems like it is not atmospheric in nature. I have seen suspect noise on channel 5 RF on rtl-sdr on a few occasions. AM and shortwave bands can be very filled with just white noise except 700-740 khz gets buzzing intermittently from 4-6 pm. This is based on outdoor antennas for these bands.

In my area there are only three cell towers within a mile away from my location. I doubt there are any more because do not think a town like Rittman would garner the attention to cell companies to put more towers. There is only about 6,000 people here.

In addition to the hd200xl antenna, my setup has a kittech preamp set to 17db and another kitztech amp set with a two way splitter with 3db loss to each. Essentially this second amp is my distribution amp Interestingly WTOV is helped at times when this self-created distribution amp is set to high levels which suggests that at times there is no overload for if there were WTOV would break.
 

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Why will receiving RF10 be impossible at the new transmitter location? At least on route 95 in southwest Wayne county I see outdoor tv towers which are pointed to Cleveland? Do you have a rabbitears analysis of the area or other info so I can see why it is not feasible for WOIO to simply receive WOIO.

Last summer I e-mailed an engineer of a western Ohio tv station, he stated that a person in Wyandot county was able to receive WJW and WLIO by simply turning their antenna in the direction of the towers. He stated that a good VHF antenna was necessary.
If not impossible, I would suspect that reception will be very unstable and prone to breakups. The current RF 10 facility barely makes it to that repeater site, with the construction permit yielding in very little improvement. Even with a very good receiving antenna mounted fairly high off the ground, I don't see this being feasible if they want that repeater to deliver 24/7 service interruption free. They'll need a microwave link or some alternate way of feeding that repeater.
 

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This is quite interesting. Here in Rittman I can sometimes see the hump over about 6-10 dbfs over the noise floor with RTl-SDR and still sometimes the signal does not decode.

How bad are the financial issues?
In the short term the financial situation at Ohio University isn't bad. Especially with the latest multi-trillion stimulus funds hitting the streets. However, the outlook is bleak for them if they can't stabilize declining enrollment. See Pandemic Deepens Ohio University’s Budget Crisis.

Someone mentioned the FM interference issue on RF6. A friend of mine has that problem. If you live near a high power religious or public radio broadcaster, RF6 is likely a problem to receive. His solution was a succession of notch filters until he found a combination that worked.
 

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If not impossible, I would suspect that reception will be very unstable and prone to breakups. The current RF 10 facility barely makes it to that repeater site, with the construction permit yielding in very little improvement. Even with a very good receiving antenna mounted fairly high off the ground, I don't see this being feasible if they want that repeater to deliver 24/7 service interruption free. They'll need a microwave link or some alternate way of feeding that repeater.
I did a rabbitears study of the site and found that a signal margin of 17.35 exists. The signal strength is -67.75 dbm. This is all for channel 10. This seems healthy enough that at least WOIO could probably get away with a setup that includes a good high vhf antenna. However, one can use a single channel antenna, amp and bandpass filter. I saw similar equipment for other channels on ebay. It costs around $1000. For instance, Blonder tongue channel 6 antennas exist on ebay but you'll have to pay 600 for them.

The channel 18 repeater is not likely because you will need about 20 db difference for co-channel reception but it will really depend on what they find on the ground.
 

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I did a rabbitears study of the site and found that a signal margin of 17.35 exists. The signal strength is -67.75 dbm. This is all for channel 10. This seems healthy enough that at least WOIO could probably get away with a setup that includes a good high vhf antenna. However, one can use a single channel antenna, amp and bandpass filter. I saw similar equipment for other channels on ebay. It costs around $1000. For instance, Blonder tongue channel 6 antennas exist on ebay but you'll have to pay 600 for them.

The channel 18 repeater is not likely because you will need about 20 db difference for co-channel reception but it will really depend on what they find on the ground.
I also did an FM study. WNCO lacks a second channel harmonic within the rf 10 bandwidth.
3121388

Rabbitears study.
 

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Currently I am having continuous reception issues with WOUC. I used to get reception for four hours almost daily using a radioshack vu-190 but when I switch to a HD200XL all reception is dropped and the signal meter bounces back and forth.
Hello, xdec32; thank you for the signal reports.

I am not familiar with the HD200XL. Would that be the HD8200XL from Solid Signal?

WOUC will most likely always be difficult for you. You are outside the area of coverage in a dead zone (no color):

xder32AVScovWOUC_1.jpg


and you have terrain and curvature of the earth blocking the signal:

xder32AVSp3WOUC_1.jpg


using different terrain profile software:

xder32AVSp2WOUC.PNG


Fortunately, VHF signals can make it over rough terrain better than UHF signals, but the noise level on VHF-Low is often very high which reduces the SNR of a signal.

My noise level is very high. A CH3 signal needs to be at least -57 dBm to have sufficient SNR,

Thor33-3Ant-8dBmVtoTV_SNRrev2.jpg


CH3 Test 8-9-2020 No4_1.jpg


I also have reception issues with WYFX. During the winter I received this well mostly throughout the day. However as soon as the temperature outdoors increases to 40 degrees the reception discontinues.
WYFX also has a difficult signal path:

xdec32AVScovWYFX.jpg


xdec32AVSp3WYFX.jpg


The problem is caused by a temperature inversion. As the air gets warmer, the signal is no longer able to bend down by refraction to your antenna.
 
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