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insane HD radio prices

Nick said:
HD radio isn't an antique yet.
Those radios that have triangles on 640 and 1240 don't even sell for as much.
640, I assume is KFI. What is 1240?

Jeff in Sa-ra-so-ta!
 
badjef said:
Nick said:
HD radio isn't an antique yet.
Those radios that have triangles on 640 and 1240 don't even sell for as much.
640, I assume is KFI. What is 1240?

Jeff in Sa-ra-so-ta!

Those triangles are the indicators for the old Conelrad station frequencies - a system of giving people emergency information about nuclear attacks. It was started in 1951 and ended in 1963.

I think it is amusing that some posters on here think the high prices for the Sangean and Sony HD tuners have something to do with the HD capability. If you consult fmtunerinfo.com, you will find that they are highly prized by FM DX'ers:

http://fmtunerinfo.com/sony.html - XDR-F1HD near the bottom. Other info:

http://www.ham-radio.com/k6sti/xdr-f1hd.htm
http://www.rwonline.com/article/sony39s-tuner-is-rich-in-features/212
http://theaudiocritic.com/plog/index.php?op=ViewArticle&articleId=35
http://kaxeengineer.blogspot.com/2008/10/kaxe-reception-issues-and-solutions.html
http://fmradiodx.wordpress.com/category/sony-xdr-f1hd-review/
http://fmdx.usclargo.com/sonyxdr.html

Here are some things about the Sangean HDT-1 and 1X

http://www.ham-radio.com/k6sti/hdt-1.htm
http://www.ham-radio.com/k6sti/hdt-1x.htm

The reviews mention HD in some cases, but it is more of an afterthought, and the hobbyists are modifying the units in some cases to force analog only reception.

There are still thousands of DX'ers actively persuing the hobby, and probably many times that number picking up more distant stations for the sake of programming not locally available. They may not even be aware of the term "DX" and the DX hobby, but they are bypassing local stations nonetheless.


http://www.ham-radio.com/k6sti/hdt-1.htm
 
cd637299 said:
badjef said:
Nick said:
HD radio isn't an antique yet.
Those radios that have triangles on 640 and 1240 don't even sell for as much.
640, I assume is KFI. What is 1240?

Jeff in Sa-ra-so-ta!

Nothing to do with KFI......see:

http://conelrad.com/about/faces.php?faces=01

cd
It must be another goment thing, similar to the emphasis on 55mph on speedometers.

There were AM radios pointing out certain clear channels back before that.

And it wasn't just WLW on the Crosleys.

Jeff in Sa-ra-so-ta!
 
badjef said:
cd637299 said:
badjef said:
Nick said:
HD radio isn't an antique yet.
Those radios that have triangles on 640 and 1240 don't even sell for as much.
640, I assume is KFI. What is 1240?

Jeff in Sa-ra-so-ta!

Nothing to do with KFI......see:

http://conelrad.com/about/faces.php?faces=01

cd
It must be another goment thing, similar to the emphasis on 55mph on speedometers.

There were AM radios pointing out certain clear channels back before that.

And it wasn't just WLW on the Crosleys.

Jeff in Sa-ra-so-ta!

It's from the bomb shelter days, they were basically in case of a nuclear attack by the Ruskies. Civil Defense would take over those local stations in case of an attack. There's a lot of stuff on youtube apout it, air checks etc.

http://www.youtube.com/watch?v=sAxjkMtJA6E
 
Conelrad was mentioned in the Twilight Zone that aired last night on MeTV. It was the great episode about the bomb shelter, where a doctor's neighbors barb him over building a bomb shelter, but then an attack alert is sounded…
 
jim 8230 said:

In the event of an emergency, the computer will be useless.

I guess, we will have NOAA radios, but I wonder how many hams will be left.

Why 640 and 240? Nothing is addressing how they arranged for those two frequencies.

My bet is KFI was the go to station for most of its existence. 1240 was a local frequency so there were more scattered around. If you couldn't receive KFI, then the local 1240 would be your choice, or visa-versa.

This must have been a West Coast program. The threat was more from over the Pacific.

Jeff in Sa-ra-so-ta!
 
badjef said:
The threat was more from over the Pacific.

Nope. The shortest route from the former Soviet Union to the US mainland was over the North Pole, which is why NORAD's old DEW Line was located in Canada.
 
badjef said:
Why 640 and 240? Nothing is addressing how they arranged for those two frequencies.

My bet is KFI was the go to station for most of its existence. 1240 was a local frequency so there were more scattered around. If you couldn't receive KFI, then the local 1240 would be your choice, or visa-versa.

Actually, all radio stations were required to either change their frequency to 640 or 1240 kHz or to go silent during CONELRAD tests/alerts. So the use of the system wasn't dependent on there being a local station normally broadcasting on one of those two frequencies; whatever stations were in your area would switch over to 640 or 1240.

And then once switched over, the stations would transmit in timed intervals, so that to the listener, the broadcast would appear to be continuous, but behind the scenes, each station would only have its carrier on the air for more than (IIRC) 30 seconds, to confuse incoming missiles which might try to home in on a radio signal.
 
Indeed, until the advent of the Emergency Broadcast System in 1963, most stations had CONELRAD transmitting capability. Our backup-backup 1kw RCA BTA-1R, 1962 vintage, has crystal-selection switches on the front panel. You can relay-select either Crystal #1 or #2, and by pushing both switches up into the CONELRAD position, the transmitter changes over to a separate always-hot oscillator circuit with its own 1240 khz (ooops, I mean "kilocycles") crystal. In this mode a status light at the top of the transmitter illuminates, indicating CONELRAD operation. Of course this circuit was disabled long ago on our rig, with the octal crystal circuit and 6146 sockets vacant.

Back around 1970-ish, during boring weekend or overnight shifts, we would switch WELM's RCA 1R to CONELRAD, effectively moving the station from 1410 khz to 1240 just to mess with our local-channel competitor WENY on 1230. Wacky college-kid hijinks.... ::)
 
satech said:
And then once switched over, the stations would transmit in timed intervals, so that to the listener, the broadcast would appear to be continuous, but behind the scenes, each station would only have its carrier on the air for more than (IIRC) 30 seconds, to confuse incoming missiles which might try to home in on a radio signal.

How was the synchronization or rather how would it have been accomplished?
 
You know, that's what's so sad about the radio biz today - it's just not fun anymore...doing crap like this is hilarious -

Savage wrote: "..., during boring weekend or overnight shifts, we would switch WELM's RCA 1R to CONELRAD, effectively moving the station from 1410 khz to 1240 just to mess with our local-channel competitor WENY on 1230. Wacky college-kid hijinks.... "

I cracked-up just reading that; back in the day by having all the different owners in town, there was so much more fun with WKRP/WPIG type hijinks, friendly competions and just sporting-type fun between stations, but not mean nasty stuff like the CC/Cumulus true hatred like there is now....and NO HD, just 15KHz of clean AM audio.
 
JohnnyElectron said:
You know, that's what's so sad about the radio biz today - it's just not fun anymore...doing crap like this is hilarious -

Savage wrote: "..., during boring weekend or overnight shifts, we would switch WELM's RCA 1R to CONELRAD, effectively moving the station from 1410 khz to 1240 just to mess with our local-channel competitor WENY on 1230. Wacky college-kid hijinks.... "

I cracked-up just reading that; back in the day by having all the different owners in town, there was so much more fun with WKRP/WPIG type hijinks, friendly competions and just sporting-type fun between stations, but not mean nasty stuff like the CC/Cumulus true hatred like there is now....and NO HD, just 15KHz of clean AM audio.

Broadcasting on an unlicensed frequency is hilarious? I thought you people hated pirate operators. That's what they were essentially doing. Not that it really harmed anything, but it was still against the rules.

You had 15 kHz of clean audio, but no cell phones or internet, only 4 channels on the teevee, no 200 channels of satellite radio, no choice other than the 5 stations in any given town.

Yeah, I'd rather have all that than just a few AM stations that sign off that night but sound good. (Well, I'd rather have everything AND that, but let's not be picky.)
 
Well, Zach, we didn't do it for very long. It was just a prank. We knew WENY didn't have a very good signal with their 250 watts on 1230 (despite their 400-foot Blaw-Knox freestanding tower) so we just did it long enough for listeners to call them to say, "we can't get you guys because WELM is coming in on top of you." One of their jocks called us to say we were coming in on their off-air monitor. I think we did it two or three times for a few minutes overnight, as I said, just to mess with them.

We would do other things. Once we replaced a console and boxed up and shipped the old skanky Raytheon to them express collect, packed in the new board's factory boxes. The staff gleefully paid the ten or fifteen bucks and ripped open the box like it was Christmas, thinking they were getting a new control room board. On the old filthy wornout console was a greeting card signed by all the WELM staff.

I could go on. You're right: we had all kinds of fun. They pulled stuff on us too. We were all mostly friends. WELM/WENY overnight jocks had each other's control room hotline numbers, and would call to chat and make sure both stayed awake. It was a nice time in the radio biz.
 
Zach said:
Broadcasting on an unlicensed frequency is hilarious? I thought you people hated pirate operators. That's what they were essentially doing. Not that it really harmed anything, but it was still against the rules.

You had 15 kHz of clean audio, but no cell phones or internet, only 4 channels on the teevee, no 200 channels of satellite radio, no choice other than the 5 stations in any given town.

Yeah, I'd rather have all that than just a few AM stations that sign off that night but sound good. (Well, I'd rather have everything AND that, but let's not be picky.)

Anyone broadcasting IBOC is broadcasting over their two adjacents without a license which is illegal according to the lame FCC.
 
KB1OKL said:
Zach said:
Broadcasting on an unlicensed frequency is hilarious? I thought you people hated pirate operators. That's what they were essentially doing. Not that it really harmed anything, but it was still against the rules.

You had 15 kHz of clean audio, but no cell phones or internet, only 4 channels on the teevee, no 200 channels of satellite radio, no choice other than the 5 stations in any given town.

Yeah, I'd rather have all that than just a few AM stations that sign off that night but sound good.
(Well, I'd rather have everything AND that, but let's not be picky.)

Anyone broadcasting IBOC is broadcasting over their two adjacents without a license which is illegal according to the lame FCC.
Unless, the FCC says you can do illegal things, since they make the rules, they can break them.

Isn't power nice?

Jeff in Sa-ra-so-ta!
 
satech said:
Actually, all radio stations were required to either change their frequency to 640 or 1240 kHz or to go silent during CONELRAD tests/alerts. So the use of the system wasn't dependent on there being a local station normally broadcasting on one of those two frequencies; whatever stations were in your area would switch over to 640 or 1240.

Not all stations were CONELRAD enabled. Only those participating in the system were required to be able to move to one of the frequencies. There were actually 1240 stations that were not part of the system.

The time periods for each station were, in theory, variable. There were only a couple of tests (five IIRC) starting with two in 1956, one in '59, one in '60 and one in '62.

http://www.americanradiohistory.com...=conelrad+test&zoom_cat[]=-1&zoom_per_page=10

... shows info on how the tests actually ran.

Most stations ran much lower power for CONELRAD as the final stage of the transmitter and the antenna tuning unit (dog house) were often severely mismatched, causing immense strain on the transmitter including tube overheating as well as distortion and other byproducts like harmonics.
 
DavidEduardo said:
satech said:
Actually, all radio stations were required to either change their frequency to 640 or 1240 kHz or to go silent during CONELRAD tests/alerts. So the use of the system wasn't dependent on there being a local station normally broadcasting on one of those two frequencies; whatever stations were in your area would switch over to 640 or 1240.

Not all stations were CONELRAD enabled. Only those participating in the system were required to be able to move to one of the frequencies. There were actually 1240 stations that were not part of the system.

The time periods for each station were, in theory, variable. There were only a couple of tests (five IIRC) starting with two in 1956, one in '59, one in '60 and one in '62.

http://www.americanradiohistory.com...=conelrad+test&zoom_cat[]=-1&zoom_per_page=10

... shows info on how the tests actually ran.

Most stations ran much lower power for CONELRAD as the final stage of the transmitter and the antenna tuning unit (dog house) were often severely mismatched, causing immense strain on the transmitter including tube overheating as well as distortion and other byproducts like harmonics.
Now, I realize we are talking about this 50 years later with a lot more knowledge of the care and feeding of tuned cavities, but did this actually work at all?

Were there any tests to see if it work in real life?

Is that the reason they chose one lower and one higher frequency - to reduce the possibility of failure due to such mismatch?

Were there any transmitter failures as a result of the tests.

I, for one, would have elected to go off the air given the pros and cons of the system.

Jeff in Sa-ra-so-ta!
 
The purpose of Conelrad was to keep Russian bomber

crews from DF'ing an AM station and "riding the beam"

as happened at Pearl Harbor.

Problem was,SAC crews got good lock-ons anyway

during some of the tests.
 
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