That's what a lot of people thought 20 years ago. The bad news with AM HD is that it causes interference with other stations. So a lot of stations stopped using it.
-
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
Saving AM Radio
- Thread starter BruceB
- Start date
That's what a lot of people thought 20 years ago. The bad news with AM HD is that it causes interference with other stations. So a lot of stations stopped using it.
In some ways, it sounds better than the FM translator at 95.3. Yet the station IDs on the air as "Legends 95.3". Crawford also recently expended some effort to increase the ERP of the translator, though there's only so much you can do with a translator on Lookout Mountain.
What keeps KLVZ afloat are weekend infomercial talk shows. There's also a couple of brokered oldies shows during the week.
Does the "all digital" AM mode stay in 10kz channel?
K.M. Richards
Program Director, The Eighties Channel™
No. There are sidebands which on an analog receiver sounds like hash.
Same with MA3, Digital Hash on adjusting frequencies
The other problem is that some stations' antenna systems simply couldn't pass the bandwidth required. Susquehanna couldn't run it on KNBR, for example. They did run it on KTCT.
(Edit: just to note that these are San Francisco-area stations, since the poster a few posts back referred to a Denver station; the geographic jumping-around could've gotten confusing.)
Last edited:
Most Class C AMs use to be 1kw daytime 250 watts at night. Depending on the transmitter, going back to the 250 at night could save possibly one third of the electric bill. Especially if the station has a FM translator. Maybe slightly modify the hours to 6AM till sunset 1KW. It would have to be voluntary so the stations without a translator could stay 1000 watts 24 7 if they wanted to. Let's get practical how much night time listenership is there at night on the class C channels?
K.M. Richards
Program Director, The Eighties Channel™
That was the old Class IV. The nighttime cut in wattage was eliminated in late 1984 and all of the IVs were allowed to be 1kw fulltime. I'm pretty sure directional arrays were either history for that class by then; if not, I believe nights were non-DA for them all. (If I'm wrong, blame the passing of four decades.)
You might be able to clarify, but I believe both 1400 and 1450 in Ventura County were directional for a time. I think this was related to the agreement with Mexico that US class IV stations within 75 miles of the border had to remain at 250 watts, until such time Mexico could get their own "Class IV's" up to speed. Apparently the nearly 150 mile salt water path between Ventura and the Mex border was considered the equivalent to less than a 75 mile land path.
BTW, there is at least one "Class IV" directional, when LA's KYPA 1230 began di-plexing or should I say tri-plexing with 1580/930 on Alvarado st. Prior to that in their old location they used their vintage wire antenna.
K.M. Richards
Program Director, The Eighties Channel™
Another presentation as fact one's own hazy memories without checking first. (To everyone: David has a wonderful resource in World Radio History, and it is incredibly easy to research these by searching the Broadcasting archives.)
Besides, I am a native of that market. I was PD of 1400 twice in my career, and it was non-directional when I got there the first time in 1978.
In fact, that happened all the way back in 1971:
There was, at the time when all Class IV stations were given 1kw nights, an interim 500w nighttime authorization for those in that border region. Perhaps that is what you are remembering.
1450 didn't go non-directional days until 1978:
Very few were DAs. One that still is: 1450 WKIP Poughkeepsie, NY. But it has a CP to go nondirectional.
The DA was aimed away from Newburgh in order to accommodate a co-ownership situation in the 1940s with WGNY. Also notable is that the Poughkeepsie Journal owned both stations. The ground conductivity in the Hudson Valley is so bad that I couldn't get WKIP in Beacon (across the Hudson from Newburgh); the DA was just icing on the cake.
Edit: I was partially right. The DA had nothing to do with the situation in the 1940s, though I was correct regarding the common ownership. The DA dates from 1963, during another era when there was common ownership between WKIP and WGNY. WKIP wanted to increase daytime power to 1 kw; competitor WEOK went to court after the FCC approved the increase, saying that the Commission should have taken the increase in overlap between the stations into account. WEOK won the court case and appeals; in order to get the power increase, WKIP agreed to install a DA for daytime operation. WKIP was ND at night.
So that DA's been around for 60 years, and will soon be gone.
One more edit: I just wanted to credit the copies of Broadcasting at worldradiohistory.com, where the WEOK-WKIP dispute was well-documented in 1962 and 1963.
Last edited:
I assume the vast majority of AM C's now are 1KW 24 7. Since this would be voluntary, outliers most likely would not opt in. Would reducing the power bill (depending on transmitter) help? I believe the lower power might extend some transmitter components life.
K.M. Richards
Program Director, The Eighties Channel™
For an ancient tube transmitter, yes. For a modern solid state, not so much.
I seem to remember from the dark recesses of my mind that WLYV-1450 (now WIOE) being 500-watts directional during the day and 250 non-directional at night. Unless they were protecting the daytimer on 1440 in Portland, I don't know why. The present-day WIOE is the standard 1000 watts fulltime.
The old Gates and Collins rigs had a rather large "filament" circuits. All tubes were on at any power level. I have heard efficiency ratings sub 60%. Supposedly a Harris MW1 on a day timer with a 500 watt PSA 1KW after sunrise, paided for itself in less than 5 years replacing an old Gates rig from the early 1960's. Replacement tubes were very expensive last time I looked (2002). IIRC they were from Russia or some former Soviet Union county. Don't know how the current political climate has effected this source.
This is why I asked for a clarification, nothing in my posts are intended to presented as absolute or empirical fact. Again that's why I asked for a clarification. I've participated on this discussion board for a long time and it's always been generally lighthearted and fun. Which I assume it's supposed to be. After all, we're, to my knowledge, not talking about state secrets here. I participate to learn, not lecture anybody.
One would think a 750 watt (assuming 100% effency) for 50% of time 12 hours would show up in the power bill.
K.M. Richards
Program Director, The Eighties Channel™
It could, again depending on the individual transmitter. Those examples you cited would cut into any savings.
Yep, HD-AM is pretty impressive isn't it? All these "there's nothing wrong with AM analog" have never heard AM-HD or full MA3.
If you do an online search for “vacuum tube manufacturers” a lot of very interesting articles and discussion comes up. Seems China, Russia and Slovakia are key sources for tubes these days, though there have been a few efforts to revive production elsewhere.
A common lament in vacuum tube discussion is expense. Also much of the existing supply is considered “NOS” or “new old stock” which might have been sitting in a warehouse for years, even decades. There are also companies that specialize in recycled tubes salvaged from vintage electronics that have been taken out of service.
I seem to find there is more online chatter about tubes for guitar amps rather than radio equipment.