Acceptable registrations in the queue through March 16 at 11:00a ET have now been activated. Enjoy! -M.W.

Terms of Use have been amended effective October 6, 2019. Make sure you are aware of the new rules! Please visit this thread for details: https://www.mibuzzboard.com/phpBB3/view ... 16&t=48619

The History of FM Radio

The technical side of broadcasting. Think IBOC is a sham? Talk about it here! How about HDTV? Post DX reports here as well.
User avatar
Turkeytop
Posts: 8854
Joined: Mon Aug 16, 2010 9:27 pm

The History of FM Radio

Post by Turkeytop » Wed Feb 24, 2021 7:16 pm



I started out with nothing and I still have most of it.

k8jd
Posts: 603
Joined: Fri Jun 28, 2013 3:35 pm
Location: Commerce, MI

Re: The History of FM Radio

Post by k8jd » Fri Feb 26, 2021 6:24 pm

I had one of trhe old low band FM radios that I got working, could hear tow trucks, Gas and electric co service trucks on it :D



User avatar
Turkeytop
Posts: 8854
Joined: Mon Aug 16, 2010 9:27 pm

Re: The History of FM Radio

Post by Turkeytop » Fri Feb 26, 2021 7:42 pm

When I was a kid, I had an old Philco AM radio. Used to get Taxi and other services just above the AM band around 1700 KHZ


I started out with nothing and I still have most of it.

k8jd
Posts: 603
Joined: Fri Jun 28, 2013 3:35 pm
Location: Commerce, MI

Re: The History of FM Radio

Post by k8jd » Sun Feb 28, 2021 12:19 pm

Wow, that goes WAY back.
Police dispachars would broadcast calls on freqs above the AMBC band. Then the partol cars would go to a "police box" phone to contact dispatch and take the calls they were near. Many old AM receivers had the "poice band" marked above 1500 kHz on the dial.



User avatar
Ben Zonia
Posts: 2143
Joined: Sat Jun 03, 2006 10:35 pm
Location: Honor

Re: The History of FM Radio

Post by Ben Zonia » Sun Feb 28, 2021 3:48 pm

Just above the Police Band kids, which ran from 1610-1720 kHz, which was often included with higher end AM/SW radios in the 1930s.

https://video.search.yahoo.com/search/v ... tion=click

They stopped using the band for Police, and maybe Taxis, because of skip causing confusion with calls.

They also used Narrow Band FM in this band for the base units of the original portable home telephones. It acted like a carrier current station, though frequency modulated, but detectable with slope detection, ending up on electric and phone lines, which sometimes were heard several blocks or more away, due to standing waves on the wires. The portable part used the 49 MHz Band.

For a while, the Police Band moved to the High HF band frequencies, where they thought there couldn't POSSIBLY have skip call confusion problems. Wrong. Of course, the 30-50 MHz still had the problems occasionally with E Skip.


"I had a job for a while as an announcer at WWV but I finally quit, because I couldn't stand the hours."

-Author Unknown

k8jd
Posts: 603
Joined: Fri Jun 28, 2013 3:35 pm
Location: Commerce, MI

Re: The History of FM Radio

Post by k8jd » Sun Feb 28, 2021 3:59 pm

My oldest son got into the Scanner listening hobby from listening to neighborhood portable phones on 49.8 MHz. :D He went to school with some of the chatty, clueless girls he listened in on.
:lol:



User avatar
Ben Zonia
Posts: 2143
Joined: Sat Jun 03, 2006 10:35 pm
Location: Honor

Re: The History of FM Radio

Post by Ben Zonia » Sun Feb 28, 2021 4:13 pm

Hebron Fire Tower Lookout, now a VHF/UHF/SHF antenna farm, had a problem with the "ultra short wave" high HF frequency skip.

https://easternuslookouts.weebly.com/hebron.html


My oldest son got into the Scanner listening hobby from listening to neighborhood portable phones on 49.8 MHz. :D He went to school with some of the chatty, clueless girls he listened in on.
:lol:
I would have been dangerous if I had been that age and had a scanner, and knew what I know now. The down side would be if they said hurtful things about YOU! BTW, until recently, it was perfectly legal. And though unenforceable if you didn't tell a third party, the technology has moved on from those frequencies and also scrambling and digital, making it much more difficult.


"I had a job for a while as an announcer at WWV but I finally quit, because I couldn't stand the hours."

-Author Unknown

WC8KCY
Posts: 154
Joined: Tue Dec 14, 2004 4:09 am

Re: The History of FM Radio

Post by WC8KCY » Mon Mar 01, 2021 1:35 am

Baby monitors still transmit in the clear on the 49.8 MHz channels. People leave them on 24/7. Some of the not-quite-FCC-compliant units put out a hot signal that can travel quite a distance.

Apparently it doesn't occur to folks that they could be easily eavesdropped upon.



matt1
Posts: 2945
Joined: Sun Apr 24, 2016 12:53 pm

Re: The History of FM Radio

Post by matt1 » Mon Mar 01, 2021 2:32 am

Did NOT heard of FM radio until late 1975 when I was 10 & 1/2 years old because my older brother hated AM radio!!



User avatar
SolarMax
Posts: 702
Joined: Sat Dec 04, 2004 5:59 pm
Location: 313

Re: The History of FM Radio

Post by SolarMax » Mon Mar 01, 2021 9:13 am

When I was a kid, my dad introduced me to shortwave listening, via a 2 band GE table-top radio. He also had a Granco FM radio, one of the few available at the time, because he knew the "Good Music" he liked was on WLDM and WWJ-FM, plus, "no static at all." I had discovered that WXYZ-FM simulcast 1270AM, which was my rock station of choice in the early-mid 60s, making it easy a few years later to discover WABX and the follow-on "free form" progressive rock stations, ahead of my classmates.



k8jd
Posts: 603
Joined: Fri Jun 28, 2013 3:35 pm
Location: Commerce, MI

Re: The History of FM Radio

Post by k8jd » Mon Mar 01, 2021 5:25 pm

When I was a teen I split my listening time between eighty M CW (had the FCC license at age 16) and 3M FMBC listening.
I saved my money and bought a three tube granco tuner and salvaged a broken pair of Crystal earphones from the School language lab and repaired them, that Hi Z was perfect match to the tuner audio output. I had to mount a salvaged volume control in a little box to control the sound level.
I made a halfwave, twinlead, dipole for 95 MHz and taped it to my bedroom celing .
Heard hi fi audio from local statons and some WX front DX from Ontario, Ohio, western MI and northern IN and IL !
I determined WJBK FM had the best sounding audio for Rock music :D
Great fun for me 60 years ago !



tapeisrolling
Posts: 257
Joined: Sat Dec 04, 2004 9:07 pm
Location: go ahead, I'm listening

Re: The History of FM Radio

Post by tapeisrolling » Mon Mar 01, 2021 9:48 pm

And I thought everyone started, like me, with a crystal radio...... Then a Knight kit radio to "Tune the World". Listening to Radio Moscow claim everything was better in Russia.



User avatar
Turkeytop
Posts: 8854
Joined: Mon Aug 16, 2010 9:27 pm

Re: The History of FM Radio

Post by Turkeytop » Tue Mar 02, 2021 6:49 pm

tapeisrolling wrote:
Mon Mar 01, 2021 9:48 pm
And I thought everyone started, like me, with a crystal radio...... Then a Knight kit radio to "Tune the World". Listening to Radio Moscow claim everything was better in Russia.


The good old days. Even Radio Moscow would be good to hear now. BBC SRI VOA RCI D Welle, HCJB, R Nederland. They're all gone.


I started out with nothing and I still have most of it.

WC8KCY
Posts: 154
Joined: Tue Dec 14, 2004 4:09 am

Re: The History of FM Radio

Post by WC8KCY » Thu Mar 04, 2021 12:58 am

I think the call letter system for the 40 MHz FM band made some sense: the middle digits represented the ones and .1 MHz digits of the station's frequency, and the letter suffix indicated the city of license.

W45D: 44.5 MHz, Detroit
W49D: 44.9 MHz, Detroit
W75NY: 47.5 MHz, New York City
W47NV: 44.7 MHz, Nashville

Right off the bat, however, some illogical letter suffixes were put into use. Lansing, for example, got XL and Rochester, NY received the A suffix. This surely would've gotten worse as the years went on.



User avatar
WOHO
Posts: 820
Joined: Thu Dec 16, 2004 12:05 am
Location: 2965 Pickle Rd.

Re: The History of FM Radio

Post by WOHO » Thu Mar 04, 2021 8:23 am

And the original FM band moved from the VHF low band to it's current location mostly due to RCA being pr*cks and trying to screw the FM inventor on his patents, if I'm not mistaken, and at great personal costs?



Post Reply Previous topicNext topic