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As most of you have probably heard, analog TV over-the-air broadcasting in the USA is due to terminate Friday night. So be aware of this if a recent residential customer starts blaming your work for making their TV set not work anymore.
It's been gone on most of the stations in Ft Myers for many months. I think it was even before the Feb deadline.
Note this only applies to "full power" stations, and that repeaters are not required to do this now. I think their deadline is with the cable deadline in two years.

Where my Mom & Dad live in rural Central Oregon, they still get their TV from analog repeaters. There are no digital stations within range. My guess is they will probably make the switch as it becomes financially convenient, i.e. when repeater components break and they can't get analog replacements anymore.
There are millions of people on the fringes who will have to invest in better antennas to get the digital signals. Analog signals have a much better range than the digital, in my opinion. It is another example of our government selling off public property to the highest bidder.
Homer - I see it as something different.

Soapbox on:

The Feds and the high tech folks told us how much better the digital TV signal was and that we should all rush out and buy the new digital TV sets.
We, as the public, made a choice. We wanted to keep things the way they had always been.
Then the government told us that we had made the WRONG choice and that they would now make it FOR us.

If all they wanted was more bandwidth, they could have done the same thing that they did many years ago with "channel 1" on your analog TV.
Just tell all the VHF channels that when they go to renew their license they'll be forced to change to a frequency on the UHF band, which already uses quite a bit less bandwidth per signal. Then they could sell off the entire VHF band...but that wouldn't address their pompous opinion that we are all too dumb to make "the correct choice" on our own.

Soapbox off.
Originally Posted by ghost307

Just tell all the VHF channels that when they go to renew their license they'll be forced to change to a frequency on the UHF band, which already uses quite a bit less bandwidth per signal.


Analog TV channels are 6 MHz wide, UHF or VHF.

http://www.csgnetwork.com/tvfreqtable.html
They sold off part of the UHF band years ago. How many remember when it went to channel 83? It only goes to 68 I think now.
Originally Posted by homer
There are millions of people on the fringes who will have to invest in better antennas to get the digital signals. Analog signals have a much better range than the digital, in my opinion.


The reason that analog TV (channel 2-13)had a better range was because it was or is in the VHF band. ALL of the digital TV stations are now in the UHF band. Telecoms have been drooling over the prospect of getting the VHF band for the last 3 decades. The main advantage of VHF band is that you can send the signal much farther with the same or less power versus the UHF band. Also you do not have the problem of nightime reflection off of the ionisphere like you have with the lower bands. Think US AM radio and CB radio during the '70's. Analog TV, US FM radio, Ham radio 2 meter band are all in the VHF spectrum. I believe maritime radios are also there.

Larry C
There are several reasons the broadcasters wanted to go digital. First they could provide 6 or more channels on their assigned bandwidth (Channel)No ghosting or snow. Stations can use adjacent channels allowing for closer spacing. Analog required guard channels assigned between each channel in each broadcast area. With broadcasters competing with cable, broadband and sat., this will allow them some more choices. Another note, all the digital stations are NOT on UHF. In most of the US broadcasters are moving off of the low VHF ch 2-6 but High band 7-13 will sill be used. Most stations were allowed the choice by the FCC to stay with their temporary digital assigned freq. or return to their old analog assignment. There is NO requirement for cable co to switch. If they do its their choice, but they cannot use the same digital broadcast format as broadcasters due to technical issues. Robert
Originally Posted by LarryC

The main advantage of VHF band is that you can send the signal much farther with the same or less power versus the UHF band. Also you do not have the problem of nightime reflection off of the ionisphere like you have with the lower bands. Think US AM radio and CB radio during the '70's. Analog TV, US FM radio, Ham radio 2 meter band are all in the VHF spectrum. I believe maritime radios are also there.

Larry,
Bear in mind that VHF spans 30-300MHz.
Even over here in NZ, the Government have been very quick to sell off any frequencies that they can.

But on the other side of the coin, VHF is really only "line of sight" communications, you really have to have something like a repeater system for communications to be of any use, especially with terrain variations.

Over here, the VHF band is littered with services that should not even be in there, the first being Television, it takes up a HUGE part of the lower end of the VHF band (around 40-52MHz) which means that radio hams like myself can't use the 6 meter band, it is the same with the 220MHz (1.5meters), because that is smack in the middle of TV2 here.

Around about 75MHz we have the Fire Service and Police, they are going encrypted next month, but what they should be doing is moving to UHF, there is already a repeater network here.

The sooner all these TV services go to digital satellite reticulation the happier we will all be.

Mind you, the frequencies could be sold to someone worse.

We've had to live with the "splatter" from the local Telecom pager tower for the last 10-15 years on 145.700 at 90-180db/m all over the 2 meter band here mad
I didn't think there was that much going on in VHF, at least in public service. All of our police and fire moved to UHF packet systems. I haven't seen a VHF whip on a vehicle in 20 years. There is still a fairly active marine band there but a lot of casual boaters are using cell phones as their main communication method. 911 has become the new "channel 16". The USCG, sheriff and the tow pirates are all carrying cell phones now.
Here VHF still used. Utilities, railroad, marine,smaller fire dept still use it mostly for tone paging. Most dispatching has moved to UHF or 800mhz (soon to move to 700)mostly trunking. Hams still have 2m 144-148mhz and 430-450 mhz the to most used bands here. Railroads use 460 for their ETD (caboose lol) but 160-161mhz for voice and control. Robert
Here in northern California, we have a mix of services using everything including loband (30-50mhz), highband (150-174mhz), UHF (450-470mhz), T-Band UHF (470-512mhz), and 800Mhz.

Most police is on UHF and T-Band, but CHP is on loband, and some of the less densely populated cities/counties are on highband VHF.

There are also a few cities/counties using 800mhz trunked systems, both analog and digital and a couple using T-band digital trunked systems,.

Most fire is on highband VHF, with a small amount of loband, UHF, and 800. Cal Fire is on highband statewide.

In general, highband tends to be the most popular, except in the urban areas, where UHF and 800 enter the picture.

In Santa Clara county, in the heart of Silicon Valley, there is one city using 800 analog trunking, the rest have police on UHF and T-band, with a few of the outlying cities, and the sheriffs office on highband. Most of the fire departments are on highband, with the exception of the city with the 800 system, and a couple on UHF and T-band.

Also, while most DTV is on channels 7 and up, there are DTV assignments in some areas all the way down to channel 2.


Hams actually have several bands in the VHF/UHF spectrum above 30mhz, including 50-54, 144-148, 222-225, 420-450 (430-450 along the Canadian border), 902-928, 1240-1300, and a bunch of stuff at 2.4ghz and higher.

I just spent the weekend operating the ARRL June VHF contest, on all of the above bands below 2.4ghz.
It has been a while since I played with my old Bearcat 210 but the last time I tried it the whole VHF band seemed pretty quiet, at least voice. There was a lot of "data" sounding stuff. I really don't know enough about it to say what I was hearing.
I used to get cops and fire all up and down the dial.

Is there a frequency assignment deal on the web these days like the old books they sold at Radio Shack
Originally Posted by gfretwell


Is there a frequency assignment deal on the web these days like the old books they sold at Radio Shack


http://www.ntia.doc.gov/osmhome/allochrt.pdf
I have that one.
I was thinking more like the old "scanner guides" that had the individual frequencies for each agency.
Back in the olden days I had a 10 channel crystal scanner in my truck and the Bearcat at home.
I'm having trouble finding a portable battery-powered converter box for my 1.5" portable LCD TV. Any of you seen one?
I haven't but there are some that work off a wall wart so I suppose you could substitute a battery.
I just plan on using an inverter with mine since I am tooling up a 12v emergency system.
I am looking for a 2 pole 3 throw drum switch so I can exploit my golf cart for storage.
www.radioreference.com
Thanks Techie. That only confirms what I thought.
There are only a handful of VHF services in my county.
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