The Worldwide TV-FM DX Association Website
DIY LOG YAGI FOR FM
Let's face it. Commercially made FM antennas are hard to find, and those you can find cost money...more money than most of us want to spend.
If you can't buy one, build one yourself. Here are plans for a good performing log-yagi with good f/b ratio and gain of around 7-8db with a length of about 96". It was made from plans at K6STI's website but those plans have been removed and replaced with updated versions of this model. But you can find the plans for this antenna here.
WTFDA presents a randomly selected group of articles for your reading pleasure. These may change from time to time so if you find something you enjoy, be sure to grab it.
Posted by Admin | February 25,2014
SDR stands for Software Defined Radio and SDRs have become very popular with DXers. An SDR usually consists of a radio in a black box that attaches to your computer with a USB cable and is tuned with software on your computer monitor. AM Dxers have been using them for a few years. A few SDRs that come to mind are the SDR-IQ, Perseus and Winradio Excalibur. Many AM DXers use these models.
FM DXers have been left out in the cold until now. The word on the street is that there's an SDR that's the equal of a modified Yamaha T85 tuner. This SDR is called the Elad FDM-S2. It covers longwave through 150mhz. Tests have shown it to be excellent for FM DXing with no overload in locations close to FM transmitters.
To read more about it go to http://ecom.eladit.com/ELAD-FDM-S2
There's another SDR under development that also covers FM. It's called AirSpy and can display a good chunk of the FM spectrum using SDR# software. It also should be more affordable than the Elad SDR
To read more about Airspy, go to http://airspy.com/
Everybody wants to know what types of equipment TV DXers use in their hobby for best results. We've asked around for info on the best CECBs (set top boxes) and DTVs. Top DTV Dxers agree that the manual tuning of RF channels with up/down buttons is a must! Unfortunately, most DTVs don't allow it. A few allow for direct entry of RF channels but most allow for channel scanning only, which makes DTV DXing harder than it should be. Channel scans take time, sometimes minutes, and during the time it takes to do a scan, a DX station could have decoded and dropped out without you ever knowing it. DXing by channel scans should be avoided if at all possible.
So, considering that manual tuning is critical for success, here is our list of DTVs and set top boxes with manual tuning. We also include those known to have direct entry tuning (enter *2* then *1* for channel 21). Direct entry tuning is not as desirable as full manual tuning, but is still better than a DTV offering only channel scans.)
SET TOP BOXES/DTVs with MANUAL TUNING
1. Insignia NS-DXA1 CECB
2. Zenith DTT-901 CECB
3. Zinwell ZAT-970A CECB
4. Coby DTV-102 CECB
5. Sansonic FT300-A (the feature is called "Antenna Level") CECB
6. Silicon Dust HDHR3 & HDHR-US (network computer controlled tuners)
7. LG 32LG30 32" DTV (9/2009), 24" LG24LN451B, 42" LG42LN5300, and probably the entire line of LG DTVs. For an example of how LG DTVs tune manually, go here. One WTFDA member purchased a LG DTV recently, compared its sensitivity to an Insignia converter box, and then decided to retire the Insignia box.
Direct Entry (of RF channels) Boxes & DTVs
1. Magnavox/Philco CECB
2. DigitalStream CECB
3. Toshiba 26" 26C100U1 DTV
4. Toshiba 26LV610U (2009) DTV
5. Panasonic 501 DTV
6. Sylvania 6427GFF DTV
7. Philips 19" 19PFL3504D/F7 (2009)
And there you have it. If you know of any others, let us know and we'll add them to the list. (Note: we do not guarantee this list to be 100% correct and cannot be held responsible for any inaccurate data).
Although analog television has ended in Canada, there are still a few analog signals to be found there.
We present an updated list of all analog and digital television stations on lowband TV (ch 2 through 6). Channel 4 seems to be a good one to watch for DTV DX. Powers, though, are fairly low.
This list was compiled by Doug Smith, w9wi and updated by William Hepburn through 03/01/2013. If you'd like to see the list, just click here.
Update 4/2/13: One of the few remaining high power analog stations left on the air in Canada, CKND ch2 Minnedosa, MB has filed to switch to DTV and move from ch2 to ch9.
Mexico has significantly modified their DTV transition plan. The Mexican analog drop-dead date is now December 31, 2015. As in Canada, stations in small cities will not be required to convert at all. However, a far larger proportion of Mexican stations are in areas that ARE required to convert.
Mexico is discouraging, but not prohibiting, use of channels 2-6 and 38-51 for DTV use.
(Update 4/10/13)Just as in the U.S. digital transition, the Mexican government is assigning second channels to their analog stations for transitional DTV use. As in the U.S., stations will eventually elect whether to use these new second channels, or their existing analog channels, for permanent DTV operation.
DTV stations in the US and Canada use MPEG-2 compression to encode their video. Mexico will allow MPEG-2 BUT they will also allow use of the more efficient H.264 compression encoder. Some use of H.264 has already been observed in use in Mexico. H.264 is not compatable with most US TV receivers.
Some analogs going dark: XEFB-2 2013, XEFE 2 2013, XEPM 2 2013, XEWO 2 2014, XHI 2 2015, XHRIO 2 2013, XHTAU 2 2015, XHP 3 2014, XET 6 2013.
From the August VHF-UHF Digest by Doug Smith, TV News editor. Oct. 11, 2012
For a list of shut down dates by city, see the complete list at Danny Oglethorpe's website.
-->(Update 7/28/13) Tijuana area analog stations have shut down and transitioned to digital television after multiple delays.
-->(Update 9/1/13) For a map showing the cities that will shut down analog television in 2014 and 2015, please click here. The map is at the bottom of the page.
WTFDA is the only Radio hobby club in North America that caters to the TV and FM DXer, as well as the amateur radio operator who looks for DX on 6 meters. The term "DX" means "distant reception", and those who "DX" look for weak, distant radio and television signals, with an eye to logging as many of these distant signals as possible or obtaining the most distant reception of a given station. TV and FM signals normally only travel 50 to 100 miles out from their transmitters. DXers love to push the reception boundaries of stations by hundreds or thousands of miles by using their skills, better antennas and equipment, and knowing when conditions are ripe for it.