KWWL has taken many calls from people watching the station on its new VHF channel 7 for digital that were never receiving Iowa's News Channel before. KWWL switched to its digital signal on Tuesday, the first TV station in eastern Iowa to do so. KGAN (CBS) channel 2 and KFXA (FOX) channel 28 switched just after midnight on Wednesday February 18th. Until Tuesday, KWWL had been broadcasting on UHF channel 55. Since the switch from UHF to VHF, KWWL is seeing some problems with viewers who use indoor and outdoor antennas.
"We can see everyone else except you, is the biggest thing I hear," said KWWL News Director JJ Murray. "Everyone I've talked to has done a great job getting ready for the switch. They have antennas, converter boxes, etc, but seeing us is a whole different issue," Murray said.
"The other stations in our viewing area are still on a UHF signal and aren't having many problems. However, KCRG will face the same problems when it switches to digital and moves from UHF to a VHF signal on June 12th," said Murray.
The lower the channel number, the better the signal travels, but that also means it can bounce around more and create an effect called "multipath". In the analog world, those would show up as a ghosted image, but in digital, we're finding these ghosted signals can confuse DTV tuners.
"The early converter boxes from a few years ago had big issues with this, even in UHF, and they improved as time went on. In fact, these latest converter boxes should do a better job at rejecting multipath than some TV's with built in tuners, since those old TV's use the older chipsets still," said KWWL Chief Engineer Jarrett Liddicoat.
Despite those advances in converter boxes, some indoor "rabbit ear" antennas cannot lock onto KWWL-DT now that it is a VHF signal.
Here are a few general suggestions that may solve the problem. Note that each person's own individual case may be a bit different.
* Do a complete SYSTEM OR FACTORY RESET on your converter box or tuner if possible. This can usually be found in the menu or settings page. Doing this helps clear out some information that is hanging these systems up. Do a complete RESCAN... not just a channel addition. If you have a digital TV, you will want to rescan your converter box first, then re-program the channels on your TV.
* The rabbit ears (VHF part of your antenna) should only be extended about 17" or about half way. All that rabbit ears do is try to match the ¼ wavelength of the frequency. When they are fully extended, that is actually for channel 2, where as we are measured at 16.996 inches. Having the ears the correct length helps so that they are a match to our frequency.
* You want your rabbit ears in a "V"-like pattern, then face it toward the Rowley, IA area just southeast of Independence. Ideally, you should place it right against a window or even outside if possible to see if you can lock the signal in. This gives the antenna one really strong signal to better lock on to instead of having the extra noise confuse it.
* If your antenna (indoor or outdoor) does not have an obvious VHF antenna, like rabbit ears, it may not be able to receive VHF signals at all. We have found some very misleading marketing in regards to antennas that claim to receive both UHF and VHF, when in reality, they are only UHF antennas. We are still researching some recommendations for good antennas to do the job. One indoor unit that claims to reject multipath well is the Winegard SS-3000. Right now, it is only available online or through an antenna retailer, and not at the major retailers.
If you have additional questions you can contact KWWL at 319-291-1200 or call the DTV helpline at 1-888-CALL-FCC. For issues with reception, you can also contact Winegard Antenna at 866-454-7566. Winegard is a local antenna company and can help troubleshoot problems with signal strength and antenna position.
You can also find additional resources on our DTV Answers page.