Man, you really live in the sticks! 😛
I bet it's beautiful there. I live in northern Louisiana, mostly flats (except the low lying areas further south filled with swamp). Fortuately Arkansas is a few hours drive away, and we always vacationed there as a kid. Mountains left a big impression on me and I love the views. A couple years ago we took a trip to Gatlinburg, Tennessee to visit my aunt and uncle on vacation, and on our way home, we took a detour through the Smokeys and drove up to Clingman's dome. 6500 feet, loved that alpine air! Pretty cold too. Unfortunately the previous nights rainfall had left a fog over the landscape (the peak was literally inside the cloud) so I couldn't see anything from the obseration deck. 🙁
Take care and good luck picking up those signals!
It still have niche applications, like hooking up vintage game consoles to your vintage tube telly.
In the flat lands of Florida most of the TV stations migrated to UHF frequencies with the digital switchover. All of the stations in the southeast corner of the state are UHF. I believe that Tampa still has a single VHF station. This is because the FCC allows a maximum ERP (Effective Radiated Power) of 1 Megawatt! ERP = transmitter power - feedline losses + antenna gain. Most TV transmitters put out about 10 KW, but it is far easier and smaller to build a TV antenna with over 30 dB of gain at UHF than at VHF.
UHF however suffers far higher propagation loss if there is any vegetation, wood, or other moist material in the path. Here in hill country, that's almost always the case in summertime, so most TV is still VHF.
All of the VHF channels 2 - 13 are still legally available for TV use. Every time the FCC steals spectrum from TV for something else (usually cellular phones), it has been from the high end of the band. UHF used to go from channel 14 to channel 83. Back in the early 80's, 70 through 83 went away. Now the UHF spectrum ends at channel 51. Note with the digital changeover, the number displayed on the TV bears no relationship with the RF channel actually being used by the transmitter.
I have several, however none of the TV's here in my basement are hooked up to cable. I am viewing this forum on one of those fancy new 4K TV's. They are the cheapest big screen computer monitor that you can buy, and my eyes aren't getting any better with age.
> All the stores here in New Hampshire are already closed.
I never thought I would be an HOUR away from the nearest RS, and that one is really a furniture store (so probably franchise, not corporate).
The three nearer stores, one corporate and two franchise (one woman-owned), all closed in the last year. The furniture store maybe hasn't got the memo; it may be closing-out as we speak (type).
I never thought I would be an HOUR away from the nearest RS, and that one is really a furniture store (so probably franchise, not corporate).
The three nearer stores, one corporate and two franchise (one woman-owned), all closed in the last year. The furniture store maybe hasn't got the memo; it may be closing-out as we speak (type).
This of us in the pro audio world are painfully aware of the shifting spectrum allotments. The FCC keeps making wireless mics, expensive wireless mics, obsolete. 😡
But I didn't know any US TV had stayed on VHF. Makes sense up in them thar hills.
But I didn't know any US TV had stayed on VHF. Makes sense up in them thar hills.
What band are these "wireless" mics? Who says you can't keep using it!
Hmmm...
https://www.fcc.gov/consumers/guides/wireless-microphone-faqs
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Many of the expensive wireless mics used the same spectrum as the TV stations. There were both VHF and UHF versions. There were several methods to determine which TV channels were available in a given geographic area including the receiver scanning for unoccupied channels, and locking out channels were TV signals could be found.
All tube TV sets, and some early vintage hybrid or solid state TV sets had tunable coils for their IF stages, and other vintage circuitry that limited their ability to reject strong signals on adjacent channels. To avoid interference the FCC had rules in place that did not allow two TV stations on adjacent channels within 75 miles of each other. This virtually guaranteed that there would be empty TV channels in just about any location in the US. Note that due to the way the VHF electromagnetic spectrum is allocated in the US, channels 4 and 5 are not adjacent in frequency, neither are channels 6 and 7.
By the time the digital switchover happened TV set technology had improved such that this was no longer a problem. The SAW filter was the big breakthrough tech. We now have megawatt TV stations occupying adjacent channels, sometimes on the same transmitting tower. There are less TV channels than there were in the 70's, and more TV stations, so available spectrum has become scarce, and empty TV channels are not a guarantee in all major markets.
The US VHF TV allocations are split in two segments. VHF low (54 to 88 MHz) is channels 2 through 6 with a missing 4 MHz between channel 4 and 5. VHF high (174 MHz to 216 MHz) covers channels 7 through 13. Most VHF use today is in the VHF high segment. I would expect some regrouping the next time there is a spectrum grab.
For the same reasons the old 30 MHz to 50 MHz spectrum for police use hasn't gone away. There are areas in the middle of nowhere that the higher frequencies just can't reach. You still see state police cars with 8 foot "low band" antennas on them in rural or heavily wooded areas, but that frequency band accounted for less than 5% of Motorola's two way radio sales.
All tube TV sets, and some early vintage hybrid or solid state TV sets had tunable coils for their IF stages, and other vintage circuitry that limited their ability to reject strong signals on adjacent channels. To avoid interference the FCC had rules in place that did not allow two TV stations on adjacent channels within 75 miles of each other. This virtually guaranteed that there would be empty TV channels in just about any location in the US. Note that due to the way the VHF electromagnetic spectrum is allocated in the US, channels 4 and 5 are not adjacent in frequency, neither are channels 6 and 7.
By the time the digital switchover happened TV set technology had improved such that this was no longer a problem. The SAW filter was the big breakthrough tech. We now have megawatt TV stations occupying adjacent channels, sometimes on the same transmitting tower. There are less TV channels than there were in the 70's, and more TV stations, so available spectrum has become scarce, and empty TV channels are not a guarantee in all major markets.
The US VHF TV allocations are split in two segments. VHF low (54 to 88 MHz) is channels 2 through 6 with a missing 4 MHz between channel 4 and 5. VHF high (174 MHz to 216 MHz) covers channels 7 through 13. Most VHF use today is in the VHF high segment. I would expect some regrouping the next time there is a spectrum grab.
For the same reasons the old 30 MHz to 50 MHz spectrum for police use hasn't gone away. There are areas in the middle of nowhere that the higher frequencies just can't reach. You still see state police cars with 8 foot "low band" antennas on them in rural or heavily wooded areas, but that frequency band accounted for less than 5% of Motorola's two way radio sales.
Does this surprise anyone?
Radio Shack, has been kicking the can for a while now. Not since they got rid of the Mach 1's, and Giant Realistic Receivers of the 70's have they been worth a damn! They used to carry lots of caps, resistors, building supplies. Most if not all Electronics stores are closing their doors. What does all of this mean? Throw away Society. China and Japan, are going to continue the streaming devices, I-phones, one hand held Phone, internet, wifi, music station, lover, etc, Whatever, and they have Monopolised the industry for music, with the younger generation.
Radio Shack, has been kicking the can for a while now. Not since they got rid of the Mach 1's, and Giant Realistic Receivers of the 70's have they been worth a damn! They used to carry lots of caps, resistors, building supplies. Most if not all Electronics stores are closing their doors. What does all of this mean? Throw away Society. China and Japan, are going to continue the streaming devices, I-phones, one hand held Phone, internet, wifi, music station, lover, etc, Whatever, and they have Monopolised the industry for music, with the younger generation.
That, and anyone ever notice how much DIY friendlier old radios, AV equipment, and game consoles are? Want to mod something by swapping out a component, or "recap" old electronics with dry or leaky electrolytic caps? It was all through hole, so some finesse with a soldering iron and a bit of Google/Forum-Fu from other owners who had performed similar mods was all it took.
Now CPUs are all ball grid array, and nearly all components are SMT, making it a PITA to repair anything. One component blows, throw away the entire device. Only interconnects or truly massive components are ever through hole anymore. And overall flimsy connectors. You could hit an original spec USB-B connector with a hammer and it probably wouldn't go anywhere. Yank your phone or expensive tablet with the microUSB cable attached, the delicate solder pads rip off, and your device is toast. Can't charge it or communicate with it. Everything is disposable, and unlike older devices that continued to function years after they were discontinued, planned obsolescence is the new marketing buzzword. "Value engineering" to cheapen out on components so that it breaks faster, often soon after the warranty expires. "Internet of Things" is another great one. Instead of a dedicated controller, let it connect to a network and use a "smart" device to control it. Great marketing strategy, using our devices to spy on us by sending out "anonymous usage statistics" so they can send user-specific targeted advertising. Then discontinue it and pull the servers offline or remove the app from the appstore. Now your network connected expensive tech device is a paperweight. Seal batteries inside the phone instead of making them user serviceable. Why? So when the battery runs out after two years of daily charge cycles, the user is forced to upgrade, ensuring repeat patronage of loyal customers in our new "throwaway society." And epoxy fill the entire thing internally to make it "water resistant." That's called progress, folks...
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Wow it takes you that long? I live in Canada and if I order by 7PM on a weekday, the parts are on my doorstep usually by noon the next day with free shipping! And they ship from the U.S as well. But You need to spend over $200 to get the free shipping. Which I always do.
When I lived in south Florida an order from Digikey took 5 or 6 days. Mouser, usually 2. Here, in the middle of nowhere, it takes 2 or 3 days from either one, however AES is in the southwest, Arizona I believe. A UPS package from them takes 8 days since it goes west to LA before turning around and going east to get here.
Yes I've ordered at 6pm before and had the package on my doorstep next day at noon. It's always the next day, and always free. And ships from the same U.S warehouse. Same with Mouser. From Texas to my doorstep the next day. I can't get that kind of service from anyone else even in Canada. And I don't even live in a major city.
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