WTXF- TV Channel 29.1 Philadelphia

[spongella]

Screen capture of the 6 MHz-wide digital signal of WTXF-TV, Channel 29.1, from Philadelphia, PA using a Nuts About Nets dongle spectrum analyzer. You can see the ATSC pilot spike at the beginning of the scan. Antenna is a Radio Shack discone.

 

[cypherstream]

Wow I didn't realize it was that high up in frequency.

 

[spongella]

A lot of channels moved from the VHF to the UHF bands when the switch from analog to digital occurred.

 

[cypherstream]

Here's what it looks like about 50 miles west.

 

[spongella]

View attachment 105803

Here's what it looks like about 50 miles west.

Nice, is that SDR# you are using?

 

[spongella]

Using SDR# and a discone antenna, here's what 29.1 looks like at this QTH (pic 1). The signal fluctuates from about -13 to -5 dB. I've used an in-line preamp to boost the signal and it works provided it is installed at the antenna.

Soon will be the TV DX season, and the dongle will show you signals drifting in and out from Tropo openings.

The DTV band goes as high as 698 MHz, used to be higher but those higher frequencies got auctioned off for the 700 MHz rebanding.

In the old days of UHF TV the channels were from 14 - 83 but over the years it got whittled down by other users and channels were chopped off.

Some DTV channels are still on VHF such as WPVI Philadelphia that is on 82 - 88 MHz (pic 2). Another is WACP from Atlantic City on 66 - 72 MHz.

The Atlantic City channel only comes in here when the band is open, and I switch to my regular rotatable TV antenna.

 

[cypherstream]

Yes SDR#. I wondered and suspected that's what those waveforms were when scanning down the dial.