TXA 21 Improving Signal Strength

Updated Jan.20, 2011

FORT WORTH (TXA 21) – TXA 21 has beefed up its over-the-air signal for viewers who watch with antennas.

The improvements mean a stronger signal that covers more area.  Crews have been working on the TXA 21 tower for several weeks in preparation for the switch, which will happen this month.

The increased signal strength should not affect cable and satellite TV subscribers.  But people who receive TXA 21 using antennas need to re-scan their digital TV tuners or converter boxes.

We switched to the new signal on Friday, January 21, 2011.

The stronger signal improves reception for many people who have had reception issues since the switch to digital television in June, 2009.

So, how do you go about doing a re-scan?  EZdigitalTV.com suggests the following:

Run the “scan” function on your converter box or digital television set, usually on the remote control, labeled “set-up” or “menu” or some similar term. Consult the owner’s manual for more detailed instructions on how to run a channel scan.

Click here to read more.

Have questions about your specific box?  Did you accidentally throw away the instructions?  Here are the manuals for the most popular models of converter boxes:

You can also check out this handy page from tv.manualsonline.com, which features instructions for many other kinds of converter boxes.


One Comment

  1. re_nelson says:

    I hope the CBS engineers can actually pull this off given the wintry weather in the forecast in the days prior to the target.

    How long will the simulcast on KTVT’s RF-11 facility continue once KXTA and KTVT light up on the new diplexed antenna?

    1. James Johnson says:

      I have been wondering how long RF channel 11 would be used for KTVT. The power bills must eat up a lot of money and most viewers watch the RF channel 19 signal (57%). Why can’t KTXA continue using channel 18 instead of moving to channel 29? I wish that the FCC would stop requiring the use of “Virtual Channels” that differ from the actual channel.

      1. re_nelson says:

        KTXA’s signal on RF-18 is constrained by short-spacing to co-channel KYTX in Nacogdoches. Moving to RF-29 allows KTXA to increase power from 220 kW to a full megawatt with an omni-directional antenna.

      2. re_nelson says:

        There is some precedence for prolonged simulcasts on VHF even after the final UHF facility fires up. WLS-TV in Chicago continues to operate on the original RF-7 as well as their new RF-44.

        Channel 11 was removed from the FCC’s allotment table for Ft. Worth. Presuming KTVT does end the simulcast sometime down the road, it’ll be interesting if anyone files for a reallocation.

  2. mike j says:

    My friends and I will sure be glad when KTXA starts to carry all of the Mavericks games . None of us understand why KTXA does not carry all of the away games and we sure would like to see the Home games also but understand that it must be a sell out before game time . Thank you , Mike Joyner Wills Point

    1. Pete R says:

      I second that one. I bought my 36″ Zenith wide screen HDTV (CRT w/2800 dpi) in 2004 and have been enjoying HDTV broadcast ever since. One of the biggest attractions was (past tense) watching Mavericks games on KTXA-21. Less than one year later our dear friend Mr Cuban who was instrumental in getting HDTV broadcast in the DFW area as well as nationwide pulled most if not all Mavericks games from the air waves and placed them on FoxSports Southwest or MAVS TV.
      I don’t subscribe to Sat or cable, never will. Mark C, you are a cheapskate.

    2. Bobby Womble says:

      The home games are carried on Fox Sports SW and I don’t believe that will change anytime soon. It has nothing to do with the games selling out. If you don’t have cable you won’t be seeing the home games.

  3. Jim Flanders says:

    Good news! My stacked Channel Master 4228s work better at ch 29 than the lower uhf antennas. I get virtual ch 11 from Dallas the most often. Now I expect virtual ch 21 to come in more often than ch11. I’m 109.6 miles from your antenna @ Lake Cypress Springs. When DTV was implemented, I went from receiving five consistent analog channels to one consistent digital channel. Replacing the huge all-channel antenna with a pair of CM 4228s gives me 3 consistent digital channels(Tyler 7 Longview 51 & 56)

    1. James Johnson says:

      How high are your antennas? Can you move them sideways one foot? Remember that high gain transmitter antennas create “beaming” effects so your antennas might not be in a beam, and at your distance from the transmitter you need to be able to “truck left” or “truck right”. Make sure that you do not pan the antenna away from the transmitter. Sometimes you can improve the received signal by raising or lowering the antenna because of beaming so make sure that the antenna is in the sweet spot for the stations that you need. If the CM 4228 is UHF only then you will lose WFAA on channel 8 and KFWD on channel 9.

      1. re_nelson says:

        Since you mentioned KFWD in your remarks, in an ideal world, KFWD would be wise to apply for the KTVT facility on RF-11 when it finally goes away.

        The short-spacing of co-channel KCEN in Temple requires a tight directional pattern for KFWD. Plus, it’s prone to tropo events. I’d think the 23 kW non-DA on RF-11 would serve KFWD better than its anemic 13 kW plant on RF-9 with that sharp null toward the south.

  4. Tyra says:

    Neither of the TV’s in my house have been able to get CBS11 for the past week! AHHH! That is my news channel…do you know what the problem is? I’ve tried to re-scan my converter box, and it’s WORSE!!

    1. Jen says:

      That happeded to me too. I re-scanned for channel 21 but now channel 11 doesn’t come in at all. I’m pretty angry about it.

  5. Aubrey says:

    I have not been able to get channel 21 for weeks now. We scan with no success. Can anyone tell me what is going on?e have done the

  6. Xenophore says:

    When is the switchover scheduled to occur?

    1. re_nelson says:

      It would be great if Dan Dobbs (Director of Engineering) would visit this thread to keep those curious up to date on what’s happening. I guess he’s really busy with the details of the big switch and has little time left over.

      The date was originally set for Friday January 14 at noon, then pushed back to Monday January 17 at noon and is now not listed. Plus, I noticed the crawls on KTXA promoting the change are no longer airing.

      Something unexpected must have arisen I suppose and thus the date is now open ended.

  7. J. Porhamer says:

    When is the re-scan for Channel 21 now scheduled? Thanks!

  8. wreck says:

    A simple update would be nice – I cannot watch the Mavs or Stars in HD until I can pull in your signal again.

  9. Lori Conrad, Communications Director says:

    We apologize for the delays; The weather has not been cooperating! But we’re happy to say that you may rescan Friday, Jan. 21 to begin receiving the signal from the new 1,000,000-watt transmitter!

    1. James Johnson says:

      I see that KTXA channel 29 is on the air now. Is it at full power?

    2. James Johnson says:

      When will KTXA channel 18 stop transmitting?

    3. Dc says:

      Read all of the latest comments on this section.

      Things are not working.

  10. wreck says:


  11. Ed in NW Dallas says:

    I just read a crawl on Ch 11 telling viewers to rescan now to keep receiving Ch 21. However until Ch 21’s transmission ceases on RF-18, my Sony TV will always see the Ch 21 on RF-18 first and store it. It will not tune 21.1 on RF-29 either since there is a virtual channel 29.1 (KMPX) keeping that from happening, like it will do with the simulcasts of Ch 11 on RF-11 and the other on RF-19.

    Question is, when will RF 18 stop transmitting? It does no good to keep rescanning the TV until RF-18 goes away. Please advise!

  12. cv says:

    I began receiving a full signal on the NEW channel assignment last night…..are you saying I need to do something again today? I was able to get the weak version on digital 18 but the strong version on digital 29 was already working GREAT last night late. I hope today’s ‘tweaks’ don’t ruin it. (Channel 8 ‘tweaked’ something a few months back and I lost their channel COMPLETELY ever since. I get all the other DFW area channels just fine though).

  13. Dc says:

    Tivo owners that get over the air antenna signals are out of luck.

    After 23 minutes with Tivo Tech support, their guide is NOT updated for this change. Tivo uses Tribune to get their guide data. but the “cable” supplier to Tribune did not update the changes for CBS.

    Here is what my Tivo / Antenna scan has got.

    21-1 No Signal Old D Freq was 18
    21-2 No Signal Old D Freq was 18

    I get 63 other stations on my Tivo / Antenna.just fine.

    I am in the 75229 postal code, North Dallas.
    That is near Inwood RD and Royal Lane.

    I believe this is part Tivo Guide problem and the
    local cable company that feeds data to Tribune, which
    is Tivo’s primary source data.

    I also believe that the local CBS affiliate has not done
    all the preplanning and followup to ensure that OTR
    Antenna users can get all the guide data.

  14. van massey says:

    DC did Tivo say how long it would take for tribune to update the database?

    1. xenophore says:

      Given that our TiVo still shows a PBS logo for ch. 2, I wouldn’t get my hopes up about Tribune getting things updated anytime soon.

  15. joe says:

    scan digitial ch 29 even if ch 29 is received. it contains a redirect to channel 21 so the tv will show ch 21 as a station. things were simplier when it was analog, ch 21 was ch 21, not a part of a signal piggybacking on ch 29.

  16. Sam says:

    After rescan, I receive TXA21 fine on both my TV tuner and computer tuner card (using the manufacturer’s software).

    However, I cannot receive TXA21 with Windows Media Center controlling the computer tuner card. I have seen this before on other stations when signal payload information is misconfigured (ie, PSIP). Media Center is very sensitive to having correct info.

    Could you have your broadcast engineers check this out?

  17. Suzanne Ogden says:

    I’ve rescanned and can’t get Channel 21 at all now. What in the world is going on? More power means nothing if I can’t get your broadcast.

  18. Bruce Bussell says:

    I have also rescanned and can’t get Channel 21 at all now. What in the world is going on? More power means nothing if I can’t get your broadcast.

  19. wreck says:

    For those having trouble — try deleting your tuner’s scan memory first or disconnect your antenna- run a scan, then re-hook-up your antenna and run the scan one more time.

  20. Pete R says:

    I cannot get TXA 21 on my Zenith HDTV, but can get it on my Samsung HDTV. Both have built-in DTV tuner ‘s. The Zenith gets KMDX on ch 29.1 (air ch 30), and nothing for KTXA either ch 18 or 21.1 or 29. The Samsung recieves KTXA on CH 21.1 (there is not a ch 21.2 as the guides indicate there is one) and this TV doesn’t indicate which channel it is carried on where the Zenith does.
    I’ve done a re-scan while the antenna is disconnected and re-scanned, but still nothing on the Zenith TV. I’ve gone directly to CH 29 and there is nothing recieved. I have been viewing KTXA-21 HDTVfor 7 years now on this TV, and am dissappointed in the current state. Please fix it or suggest how to tune it in.

    1. Pete R says:

      I checked the signal strength on both TV’s and the signal for RF CH 29 is lower than I was getting on CH 18 for KTXA-21 before the change-over to the different RF carrier channel. I repositioned my antenna by ~3 degrees toward the transmitter and now get it on both TV’s.
      All is good, but strange that the new higher power signal is lower than before.
      I can recieve 68 digital channels between DFW and Sherman/Ardmore/Ada, OK from my 75078 zip code, a >100 mile radius with a Winegard 4 ft wing shape bi-directional antenna mounted in my attic.

      1. re_nelson says:

        Unfortunately adding an image to this message isn’t possible but you can see a graph illustrating my findings as message 6162 in the Dallas, TX thread at http://www.avsforum.com.

        In brief, using a pro-grade signal analyzer at my location (75035), what I observed is that the new 1 MW facility on RF-29 is significantly hotter than the 225 kW on RF-18.

        RF-18: 12.5 dBmV
        RF-29: 26.8 dBmV

        But, the MER (Modulation Error Ratio) is NOT as good on the new facility. Most consumer signal meters display some combination of raw signal power received and then factor in both MER and BER. Thus, it’s not possible to decompose a single reading into its constituent values.

        The chart I referenced above makes this dramatically clear.

        For factors unknown (since the CBS engineers are likely busy and don’t frequent this forum), the new plant on Tar Road, while it definitely is putting out more raw power isn’t as “clean” as the former facility at the Highway 67 location. My wild guess is that exciter may need some fine tuning.

        In the digital transmission/reception world, sheer power plays a secondary role compared to delivering a clean decodable bitstream with minimal errors and noise.

  21. rjlackey says:

    I’ll join the crowd, can’t get the new signal on 21-1. On my 52 in HDTV can scan and get signal with 100% signal strength but as soon as I change channels and come back to 21 no picture. My computer TV card will not receive the signal at al ( 0 signal strength). Hope you fix this soon.

    1. re_nelson says:

      Some of you may find that an alternate venue for these questions concerning KTXA reception problems is:


      That’s a technically-oriented site (not associated with CBS or any other broadcaster). It’s possible that your queries will be read by more people over there.many of whom could have similar equipment to what you have.

  22. Bruce Bussell says:

    I have lost my signal for channel 11-1 tonight, where it was OK yesterday, I get the 11-1 channel number but no signal. What happened. Has anyone else also lost ch 11-1. Also I am waiting awhile to rescan for ch 21-1 until CBS or someone else supplies some answers.

  23. re_nelson says:

    Whoops! In my earlier posting of January 22, 2011 at 3:00 pm, I made an error that I caught just now mentioning KTXA’s former facility on Highway 67.

    Except for just a few weeks after the transition, KTXA has been where they are now,the Richland site at 2133 Tar Road. So the physical address of KTXA’s transmitter didn’t change when they lit up on RF-29. Instead the new to-mounted antenna is about 300′ higher on the tower structure than was the most recent incarnation of KTXA on RF-18.

  24. Bruce Bussell says:

    I am getting channel 11-1 again now. But I will wait awhile before rescanning for ch 21-1, to allow CBS to get it working OK.

  25. James D says:

    On analog I had three TV’s on one antenna,on digital with the box only one tv per ant. US gov has done it again. The digital will not go through the large trees that are between my house and the broadcast ant as well as the analog would . Its been a battle sense the digital started. I hope the rest of the broadcasters also work on thier signals too

  26. Calvin NDallas says:

    Since you’ve boosted your power, you’ve eliminated all free reception of any television signals in the area near Keller Springs and the Dallas North Tollway. I now receive ZERO CHANNELS due to your good work. My television is now just a monitor for my DVD player. I needed to give up watching television anyway.

    Thank you,

  27. Ed in NW Dallas says:

    Calvin NDallas there’s really no way that could happen as a result of KTXA’s broadcast channel change. More likely you have a problem with your TV, or your antenna is disconnected. I am not that far from you, and all reception is good here after re-scanning two Zenith converter boxes, a Sony TV, a Samsung TV, and a DTVPal DVR.

  28. Sammy says:

    We still can’t get Channel 21 with our tower-mast antenna (over the air, of course) but are now receiving KHOU out of Houston. What the heck? Oh, well, nice tradeoff, I guess.

  29. Arthur says:

    I live in Midlothian and have totally lost channel 21
    I’ve rescanned several times and it just doesn’t have a signal in my area.
    I use an attic mounted antenna and don’t have any problems with any other channels except an occasionally weak or fading channel 8
    Any suggestions?

    1. Dc says:

      1. Try adding a power amplifer to the antenna leadin.
      2. Get bigger antenna.
      3. Mount antenna on roof.
      4. do all three above.

      I did number 4 and that really helped.

    2. Ed in NWDallas says:

      Midlothian is only about 5 miles from Cedar Hill. You have another problem, but not signal strength. Are you doing a full scan or just add new channels scan? Try disconnecting the antenna, re-scan to erase the stations in memory, the hook up the antenna and do a fresh scan. You should be receiving all the main stations with full signal, even Ch 8 on VHF.

      1. Arthur says:

        Your method worked perfectly although, you have to eliminate all of your favorites before the “no source scan” as I learned but you were RIGHT ON!
        Thank you!!!!

  30. frustratedwith21 says:

    before rescan 21-1 came in at 85% strenth, now its is less than 50%. 21-2 is so weak it won’t tune in. What is the truth on your signal strenth increase? Did you move the new transmitter to Houston?

  31. LAH says:

    i’ve scanned my digital tv (have rabbit ears; no way i can mount anything on my roof.. i don’t do heights🙂 ).. and i’m not getting a darn thing except “no signal” rolling and flashing across my screen even tho it does show 1 (one) station found.. this is bordering on absurd. any ideas.. it’s a Vizio TV. thanks,

  32. Lemastre says:

    Did the promulgators of HDTV know that over-the-air signals were uncertain of arriving anywhere reliably? And is the situation with channel 21 merely a temporary failure of technology to perform as needed? For instance, do HDTV sets have a circuit that blocks signals exceeding a certain power?

    Since most TV stations still have antennas on towers, I suppose it’s easy enough to put their signals into the air. But I imagine the stations expect cable or satellite services to totally supplant over-the-air in the near future, making attempts at over-the-air transmission obsolete. In the meantime, maybe an antenna maker can devise an antenna that works better for HDTV.

    At my house atop Flagpole Hill in northeast Dallas, I’ve a rooftop antenna aimed at Cedar Hill. Channel KTXA, 21.1, disappeared from my screen about the time its power was increased. Sometimes KTXA appears when I punch in channel 29.1, but usually a Spanish-language station is found there.

  33. Noonin says:

    I moved my antenna 5 feet and rescanned. Have 21 HD now. Technology rules.

  34. Bobby Goswick says:

    What can be done for Breckenridge to get KTXA so that we can get the Ranger games being televised during the preseason games. We have SuddenLink Cable?

  35. JC says:

    I have rescanned and rescanned and still no reception for ch21 KTXA. I have even moved the antenna and still no signal. Reception prior to the change was excellent and now nothing…and I see many comments indicating simialr issues. I live in Lewisville,

  36. Jordan says:

    I want to leave a comment, I am not sure what I can do about it, but before the Thunder came to Oklahoma I loved watching the mavericks and I am a huge rangers fan but I can not ever watch the games on Fridays because they are only played on KXTA and living in Oklahoma City we can not get your station, I can’t even watch them on MLB extra innings because it says I am to close and that it is on local tv witch is a lie because kxta is not local for me and there is no way to watch my teams. Even when Mavericks are on Fox Sports and the Thunder is not we get blacked out. I just wanted to rant somewhere.

  37. Jay michaelson says:

    Still not getting signal. Rescan all the time. Really like you channel. Cable and u-verse is not in our area.

  38. mike j says:


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