They used to be, but not any more. I had that rule changed.
-
Get involved.
We want your input!
Apply for Membership and join the conversations about everything related to broadcasting.
After we receive your registration, a moderator will review it. After your registration is approved, you will be permitted to post.
If you use a disposable or false email address, your registration will be rejected.
After your membership is approved, please take a minute to tell us a little bit about yourself.
https://www.radiodiscussions.com/forums/introduce-yourself.1088/
Thanks in advance and have fun!
RadioDiscussions Administrators
FCC to consider ongoing operation of existing FM6/Franken FMs, Expanded FM Band and Elimination of Reserved Band Protection Requirements
- Thread starter Michi
- Start date
A
AnyHuman
Guest
Correction, 3 out of the 4 I mentioned have been off since the beginning of May. 1 of them has not, but it's run by the same people as one of the other silent ones.
9 or 10 would simply be a logic level on a single pin of the device. FM bandwidth could be also as simple as a pair of pins that would generate a logic table of four entries for a FM bandpass selector.
Nope, not rocket science at all.
Pretty much every portable radio I've seen in the past few years has had a switch somewhere to change between 9kHz and 10kHz spacing on AM, and several have had the "Japanese" FM band included, particularly the Chinese brands. The problem is that nobody except radio geeks like me buys portable radio receivers any more.
Japan and Brazil are outliers in expanding the FM broadcast band to accommodate new stations and migrants from AM. Most countries are migrating their AM stations and expanding choice using digital platforms, usually DAB. It seems to me that if listeners are going to be required to buy a new receiver to hear the new stations, it may as well be a wholesale upgrade to digital broadcasting, rather than a continuation of FM.
But that's the problem.. They won't bother.
TV moved to higher channels because of ATSC V1 and LOW ERPs in lowband just does not work..but ATSC V3 will bring lowband back to life and I see full power stations looking at returning to "home" as operating cost will be cheaper on lowband vs V highband or UHF hi power. Watt for watt, lowband gets the best coverage but 8VSB was a big mistake...
As an engineer whose been in the business for 45+ yrs AND a station owner, I have major reservations about FM expanding down below 87.7...
AM needs better RECEIVERS...Noise blanketing, better IFs, etc can make an AM radio sound great...but unless the damn commission gets off it's ass and demands it from rcvr manufacturers, it won't happen..this piecemeal "revitalization" is hogwash...
Better receivers will not resolve AM's issues. The biggest problem is that in the top 100 markets, there are less than 90 stations on AM that cover at least 80% of the Nielsen market with a usable signal day and night (10 mV/m).
As to receivers, close to 50% of radio listening is in cars today, and it will take 12 to 13 years to even get half of all cars to have an "improved" AM section were new rules to be put into effect. And nearly nobody buys stand-alone radios today.
It won't happen because most of the receivers today are made in China, and it's all a low priority over there. When receivers were made in the US, there was an adherence to certain quality standards. Those don't exist in China. AM radio isn't the profit center that computers and phones are. No profit means no quality.
Either a "new" band or better AM radios have the problem of needing people to buy and carry new radios, which they aren't
Wait, what?? DTV doesn't work on low band VHF due to terrestrial noise, not the modulation type. ATSC 3.0 is just additional compression. Has nothing to do that would fix noise floor.
And would any of that mean new listeners would flock to AM again? I think we both know that answer...
H
Harvey_Dogg
Guest
Also, LPFM's and translators are a secondary service. That means they can be kicked around on the FM band. So expand the FM band down to 76 MHz might be really bad news and the smell of death for those signals.
Building a new FM on 76 MHz in 2025 is a worse idea than building a new FM in 1950.
TV Channel 5 might be good for long range WIFI.
Building a new FM on 76 MHz in 2025 is a worse idea than building a new FM in 1950.
TV Channel 5 might be good for long range WIFI.
Last edited by a moderator:
That is not happening in reality. If anything TV stations are migrating off of VHF (especially low VHF) because of receiver antenna issues. Consumers do not want (or can't) install those big color approved Radio Shack big outdoor antennas on their roof. With the new ATSC3 services that will better support mobile applications, the last thing that people are going to want to do is install a giant antenna that is capable of reception of a wideband signal at 54 MHz on their vehicle. Currently, Channel 6 is down to 9 full-service stations and one more has a granted CP to go to UHF. There is also movement in progress in stations moving off of Channel 5. Most of the interim ATSC3 operations are taking place in UHF spectrum. The only ATSC3 on Channel 6 are the LPTV stations that are running FM6. Elsewhere on low VHF, I believe there is only one other ATSC3 LPTV station and that's it.
The concept of expanding FM for new noncommercial radio works better because (1) the reserved band is already crowded and underrepresented, (2) it would not require any forced migration of stations and listeners (vs. using the spectrum for transitioning AM stations) and (3) it could reach more specialized communities that are not represented on radio today and only those who want to pick up the new stations would need to buy new radios. The concept of forced migration of listeners and stations in other nations is much more doable because there are far fewer migration eligible broadcasters there then here in the USA. Japan has about 50 commercial AM broadcasters for the entire country and uses 100 kHz spacing on FM, so it will be easier to move them over. They also do not have any active services in the 95~108 band (this spectrum was originally allocated for something they called "multi-media broadcasting", but that never panned out..) so it may be easier to extend the FM band even further there if necessary.
A
AnyHuman
Guest
AM really is only good for talk radio... Unless you're a radio nerd.
I say let all AM stations move to FM, maybe open up down to 76... But nowadays AM transmitters are just wasting electricity given the bad sound quality. People can hear Spotify over AM, I 100% prefer good quality audio over something that sounds like it's meant for truck/delivery drivers to receive updates on shipments/deliveries.
I say let all AM stations move to FM, maybe open up down to 76... But nowadays AM transmitters are just wasting electricity given the bad sound quality. People can hear Spotify over AM, I 100% prefer good quality audio over something that sounds like it's meant for truck/delivery drivers to receive updates on shipments/deliveries.
Oh you are wrong on V1 vs V3...8vsb vs OFDM modulation...15db improvement in noise and co channel rejection over what we see now...it's not just about 4k....but then what do I know?? I've only been a broadcast engineer for 47+ yrs
Sorry, I work in TV too and ATSC 3.0 just allows more bits in the bucket, ultimately allowing more content per 6Mhz of channel real estate. Has nothing to do with your tenure being in the same business as I'm in.
Noise floor effects the reception side and as Michi already pointed out; because of the longer wavelength at lower frequencies, physically much larger antennas would be required. The reason OTA reception of DTV signals is as popular now, (19-20% of TV viewing on average) is because one could use a small antenna stuck to an apartment wall or window. Combine that, with much lower field strength, and ATSC 1.0 or 3.0 are sketchy to useless in the lower VHF bands.
Last edited:
It's a pity you think that way... obviously you are not familiar with OFDM operation...btw that's the same method being used in all digital AM, which exceeds analog operation and range tests so far PROVES it covers farther than predicted analog mV levels...wow, it works at MW, where the noise floor is even worse but not lowband VHF??
Oh lordy...I guess all the facts and figures are wrong..
It's not just more bits in the bucket...but a true engineer would know that..
Let's not turn this thread into a battle of qualifications. The facts are that so far, only one full-service TV station (KCWX, Fredericksburg, TX) is running ATSC3 on Channel 5 (this station also had filed and was granted a rulemaking to move their primary operations off of Channel 5 to move to Channel 8 where they are building a 6-site DTS system). Only one LPTV station is operating ATSC3 on Channel 2 (KBRO-LD, Denver, CO) and the various LPTV stations on Channel 6 running it, mostly in order to support FM6/Franken-FM operation.
Oh, sure I am: Coded Orthogonal Frequency-Division Multiplexing. It's been around for years. There was a battle when the ATSC was deciding whether to go with their new digital modulation standard, or COFDM, which is/was being used in Europe. But, like any modulation scheme, one size doesn't necessarily fit all needs. COFDM has a lot of practical advantages, but can't overcome challenges of physics like terrestrial noise floor or the need for physically longer antennas. It's too bad you choose to believe marketing hype instead of the actual application therein.
Oh I recognize how well MA3 works on AM, as I frequently listen to WWFD on my way into work every weekday morning. Like anything digital, it's great until it isn't. And that's the challenge with anything relying on reception of digitally-modulated carriers; cliff effect. Excessive noise from consumer products like replacement LED bulbs, noisy switching power supplies, or speed controls on hybrid buses driving by cause a mute. Radio nerds will be much more tolerant of sudden drop-outs, but radio nerds aren't the average consumer. One of my DTV stations is a megawatt ERP, omni, on channel 34 that covers two states and D.C. It isn't uncommon to get an E-mail from a concerned viewer just a few miles away that they suddenly lost reception. Typically the resolution is to move their antenna away from a noise source, or just re-scan their TV. This is in pretty ideal transmission conditions, but the typical variable reception conditions. Now imagine increasing the noise floor by an average of 20dB. Then lets drop the ERP to 5kW. Then ask viewers to install a much larger VHF antenna or some sort of rabbit ears? Yeah, none of that would fly.
I'm not arguing the figures are wrong in laboratory or controlled conditions. The fact of the matter is our listeners/viewers don't dwell in laboratory or controlled-testing conditions. One must include the reception variables which, from an 'everything is already available on 'my iPhone' consumer market, makes receiving DTV signals at low VHF frequencies a impractical proposition.
Oooo, I'm so wounded! "Yuh got me doc!" (Bugs Bunny to Elmer Fudd reference) I'm sure over the years you've had to deal with listener reception issues. ATSC 3.0 is just a modulation standard, who's main advantage is more bits in the bucket. Someone who is as seasoned engineer, should also be considering the consumer interest given the environment any such station would be placed. It costs a lot of money to build or move frequencies. I sure wouldn't hire any engineer who would believe what amounts to marketing hype without looking at all the other potential ramifications. Lack of appropriate research could cost the company a lot of money. You flunked that test.
- Status