KFWD is going to get harder to receive this summer

[JHBrandt]

From KFWD's app for an STA:

BEGINNING IN MAY, HIC ANTICIPATES THAT TOWER CREWS WILL BE MAKING SUBSTANTIAL MODIFICATIONS TO THE KFWD(TV) TOWER. TO ENSURE THE SAFETY OF THESE WORKERS, HIC INTENDS TO CEASE OPERATIONS WITH ITS LICENSED FACILITIES AND COMMENCE OPERATIONS PURSUANT TO THIS STA FROM THE WFAA(TV) TOWER.

THIS STA FACILITY PROPOSES OPERATION WITH AN EFFECTIVE RADIATED POWER OF 0.546 KW .... DATES OF STA ARE INTENDED TO BE FROM MAY 1, 2012 TO JULY 31, 2012.

546 watts?!? Heck, even lowly KSFW is asking for 3000 watts!

KFWD has been coming in at over 90 on my Philco - and it's pretty stingy with 90+ readings (besides KFWD, only KTVT, KMPX, KDAF, and KSTR get up there regularly). I'll be fascinated to see how far KFWD drops.

 

[K5ING]

That figures. I'm halfway between Denton and Decatur, and I get every single spanish-speaking-religious-trying-to-sell-you-something station in the DFW area, but the ones that I actually watch (among them, 52 and 31) are screwing with their transmitters. *Augh!*

 

[tripinva]

Aux transmitters must constrain their contours to within the licensed contour. Since the antenna in question is an omni but the licensed antenna is not, they have to limit power to the power used on the current antenna in the deepest null, which would appear to be about 0.546 kW.

- Trip

 

[JHBrandt]

Aux transmitters must constrain their contours to within the licensed contour. Since the antenna in question is an omni but the licensed antenna is not, they have to limit power to the power used on the current antenna in the deepest null, which would appear to be about 0.546 kW.

- Trip

It's understandable; otherwise there would be interference issues with KCEN in Waco. And there just isn't a better-suited VHF antenna in the area for KFWD to piggyback onto during the construction.

Nevertheless, it's a shame for viewers. At least KTXD/47 should have Me-TV on the air before this happens.

BTW, the predicted service contour for the STA seems a tad optimistic to me. We're talking a 14dB drop or so; yet: http://www.rabbitears.info/contour.php?appid=1489409

I guess that's about right for a good VHF outdoor antenna, but it makes me wonder if anyone does similar coverage plots for indoor antenna users? (I'd guess they'd be calculated the same way except with a different cutoff point.) I suspect there'll be a lot of folks who lose KFWD during this project (even though they're within the official service contour) because they rely on smaller antennas.

 

[tripinva]

I adjust the Longley-Rice maps to some degree for indoor antennas. My maps chop 5 dB off for high-VHF and 13 dB off for low-VHF, and are run at receive antenna height of 13 feet instead of 30 feet.

The contours I generate using the FCC's method, since they are really used more for allocation issues than for coverage.

- Trip

 

[eskipper411]

So, would I be able to receive it here in Decatur with a 50 foot antenna?

 

[JHBrandt]

So, would I be able to receive it here in Decatur with a 50 foot antenna?

It's VHF and IIRC you use a CM-3020 so it may be possible. Looks like at 50 & 300 degrees, KFWD will be about 14dB weaker during the upgrade. You'll lose a bit less in Decatur but I'd still estimate 13.5dB. Go check TVFool for your address and height (50 feet), find the noise margin for KFWD (RF 9), and subtract 13.5dB and you'll be able to see where it's likely to end up in the rankings.

If it winds up among stations you don't get now, you'll probably have trouble. An even bigger antenna could add back a few dB via higher gain, but there aren't many bigger than the 3020 and the ones that are bigger are also expensive. May not be worth it for only 3 months (probably less since I suspect they'll try to get this done as fast as they can).

 

[jd]

This whole KFWD coverage issue (the regular signal, and now the STA) is just baffling. Having three full-power stations along the I-35 corridor (in D/FW, Temple/Waco and San Antonio) all on the less than desirable channel 9 makes no sense at all. It's not like there wasn't plenty of time to head off potential conflicts.

 

[eskipper411]

So, would I be able to receive it here in Decatur with a 50 foot antenna?

It's VHF and IIRC you use a CM-3020 so it may be possible. Looks like at 50 & 300 degrees, KFWD will be about 14dB weaker during the upgrade. You'll lose a bit less in Decatur but I'd still estimate 13.5dB. Go check TVFool for your address and height (50 feet), find the noise margin for KFWD (RF 9), and subtract 13.5dB and you'll be able to see where it's likely to end up in the rankings.

If it winds up among stations you don't get now, you'll probably have trouble. An even bigger antenna could add back a few dB via higher gain, but there aren't many bigger than the 3020 and the ones that are bigger are also expensive. May not be worth it for only 3 months (probably less since I suspect they'll try to get this done as fast as they can).

KFWD clocks in at 97% on my sig meter but is 0% during tropo events that come in from the south which I get very easily here.

 

[JHBrandt]

So, would I be able to receive it here in Decatur with a 50 foot antenna?

It's VHF and IIRC you use a CM-3020 so it may be possible. Looks like at 50 & 300 degrees, KFWD will be about 14dB weaker during the upgrade. You'll lose a bit less in Decatur but I'd still estimate 13.5dB. Go check TVFool for your address and height (50 feet), find the noise margin for KFWD (RF 9), and subtract 13.5dB and you'll be able to see where it's likely to end up in the rankings.

If it winds up among stations you don't get now, you'll probably have trouble. An even bigger antenna could add back a few dB via higher gain, but there aren't many bigger than the 3020 and the ones that are bigger are also expensive. May not be worth it for only 3 months (probably less since I suspect they'll try to get this done as fast as they can).

KFWD clocks in at 97% on my sig meter but is 0% during tropo events that come in from the south which I get very easily here.

Nighttime interference from KCEN will be a problem even more often during the upgrade, particularly during May when tropo is more frequent. I wish there was some way to urge KCEN to find another frequency to broadcast on.

 

[JHBrandt]

KFWD is going to get harder to receive this summer....

... but it may get easier to receive afterwards. KFWD has re-applied to increase power to 55 kW.

The original CP for the power increase was about to expire and just about everyone thought KFWD would never go through with it. But it seems they're at least keeping their options open.

I live in a good spot for KFWD. KCEN is about 35 degrees off-axis so I rarely lose KFWD during tropo episodes. (That may change during the upgrade period.) Currently in S. Garland KFWD comes in reliable & strong even at only 13 kW, so ironically I doubt going to 55 kW will cause more than a blip on my signal strength meters. But it'd really help folks in the Frisco area, particularly during tropo ;D

 

[JHBrandt]

Looks like they pulled the trigger. Signal reading (in arbitrary uncalibrated Philco converter box units) dropped from 90 yesterday evening to about 60 this evening.

 

[Bob E. Nelson]

Looks like they pulled the trigger. Signal reading (in arbitrary uncalibrated Philco converter box units) dropped from 90 yesterday evening to about 60 this evening.

I just checked on the Sencore when I saw your post. KFWD is still at the same raw power level. In fact all of the readings, including MER and BER, are at their normal levels as of 00:20.

 

[JHBrandt]

Looks like they pulled the trigger. Signal reading (in arbitrary uncalibrated Philco converter box units) dropped from 90 yesterday evening to about 60 this evening.

I just checked on the Sencore when I saw your post. KFWD is still at the same raw power level. In fact all of the readings, including MER and BER, are at their normal levels as of 00:20.

I know; it was completely back to normal the very next day, but I haven't had the chance to get back on and post a correction until now.

I figured it was either:
1. A test;
2. An unrelated fluke; or
3. The fastest TV transmitting antenna upgrade in world history! ;D

 

[eskipper411]

Looks like they pulled the trigger. Signal reading (in arbitrary uncalibrated Philco converter box units) dropped from 90 yesterday evening to about 60 this evening.

3. The fastest TV transmitting antenna upgrade in world history! ;D

That would be phenomenally fast but bet our guys in the sky can do it! ;D

 

[JHBrandt]

Looks like they pulled the trigger. Signal reading (in arbitrary uncalibrated Philco converter box units) dropped from 90 yesterday evening to about 60 this evening.

3. The fastest TV transmitting antenna upgrade in world history! ;D

That would be phenomenally fast but bet our guys in the sky can do it! ;D

Did they actually do a lightning-quick upgrade this summer? All I ever saw were 2 days where they were very weak. The second time I didn't even post, since I figured it might be just another test or fluke. It's been at full power every other day, except maybe for one or two days when I didn't bother to check. Now they've already switched to MundoFox; I would've thought they'd finish the upgrade first.

 

[JHBrandt]

Since last Saturday KFWD's signal quality has been unusually bad. Here's Bob Nelson's SQ graph: http://kb8u.ham-radio-op.net/render_graph/101A67C8/tuner0/KFWD/-6days/now

Signal strength seems normal though. Could Saturday's storms have damaged something, or did KCEN in Waco bump up their power? (Due to the government shutdown, I can't check the FCC queries.)

 

[julesism]

We both dipped S/N on the second half of Saturday but his is more drastic than mine:
http://kb8u.ham-radio-op.net/render_graph/10345B47/tuner0/KFWD/-6days/now

 

[JHBrandt]

Whatever the problem was, it apparently got fixed last Friday. It's been back to normal since then.