OT. Car radios

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Model T Ford Forum: Forum 2017: OT. Car radios
Top of pagePrevious messageNext messageBottom of page Link to this message  By Eugene Adams on Saturday, March 25, 2017 - 11:11 pm:

Seems like cars have always had radios, but they didn't.

Here's the story:

One evening, in 1929, two young men named William Lear and Elmer Wavering drove their girlfriends to a lookout point high above the Mississippi River town of Quincy, Illinois, to watch the sunset. It was a romantic night to be sure, but one of the women observed that it would be even nicer if they could listen to music in the car.

Lear and Wavering liked the idea. Both men had tinkered with radios (Lear served as a radio operator in the U.S. Navy during World War I) and it wasn't long before they were taking apart a home radio and trying to get it to work in a car.

But it wasn't easy: automobiles have ignition switches, generators, spark plugs, and other electrical equipment that generate noisy static interference, making it nearly impossible to listen to the radio when the engine was running.

One by one, Lear and Wavering identified and eliminated each source of electrical interference. When they finally got their radio to work, they took it to a radio convention in Chicago.

There they met Paul Galvin, owner of Galvin Manufacturing Corporation. He made a product called a "battery eliminator", a device that allowed battery-powered radios to run on household AC current.

But as more homes were wired for electricity, more radio manufacturers made AC-powered radios. Galvin needed a new product to manufacture. When he met Lear and Wavering at the radio convention, he found it. He believed that mass-produced, affordable car radios had the potential to become a huge business.

Lear and Wavering set up shop in Galvin's factory, and when they perfected their first radio, they installed it in his Studebaker. Then Galvin went to a local banker to apply for a loan. Thinking it might sweeten the deal, he had his men install a radio in the banker's Packard.

Good idea, but it didn't work . Half an hour after the installation, the banker's Packard caught on fire (They didn't get the loan). Galvin didn't give up. He drove his Studebaker nearly 800 miles to Atlantic City to show off the radio at the 1930 Radio Manufacturers Association convention.
Too broke to afford a booth, he parked the car outside the convention hall and cranked up the radio so that passing conventioneers could hear it.

That idea worked -- He got enough orders to put the radio into production.

WHAT'S IN A NAME
That first production model was called the 5T71.

Galvin decided he needed to come up with something a little catchier. In those days many companies in the phonograph and radio businesses used the suffix "ola" for their names -

Radiola, Columbiola, and Victrola
were three of the biggest.

Galvin decided to do the same thing, and since his radio was intended for use in a motor vehicle, he decided to call it the Motorola.

But even with the name change, the radio still had problems:
When Motorola went on sale in 1930, it cost about $110 uninstalled, at a time when you could buy a brand-new car for $650, and the country was sliding into the Great Depression.
(By that measure, a radio for a new car would cost about $3,000 today.)

In 1930, it took two men several days to put in a car radio --
The dashboard had to be taken apart so that the receiver and a
single speaker could be installed, and the ceiling had to be cut open
to install the antenna.

These early radios ran on their own batteries, not on the car battery, so holes had to be cut into the floorboard to accommodate them.

The installation manual had eight complete diagrams and 28 pages of instructions. Selling complicated car radios that cost 20 percent of the price of a brand-new car wouldn't have been easy in the best of times, let alone during the Great Depression.

Galvin lost money in 1930 and struggled for a couple of years after that. But things picked up in 1933 when Ford began offering Motorola's pre-installed at the factory.

In 1934 they got another boost when Galvin struck a deal with B.F. Goodrich tire company to sell and install them in its chain of tire stores.

By then the price of the radio, with installation included, had dropped to $55. The Motorola car radio was off and running. (The name of the company would be officially changed from
Galvin Manufacturing to "Motorola" in 1947.) In the meantime, Galvin continued to develop new uses for car radios. In 1936, the same year that it introduced push-button tuning,
it also introduced the Motorola Police Cruiser, a standard car radio that was factory preset to a single frequency to pick up police broadcasts.

In 1940 he developed the first handheld two-way radio -- The Handy-Talkie for the U. S. Army.


A lot of the communications technologies that we take for granted today were born in Motorola labs in the years that followed World War II.

In 1947 they came out with the first television for under $200.

In 1956 the company introduced the world's first pager; in 1969 came the radio and television equipment that was used to televise Neil Armstrong's first steps on the Moon.

In 1973 it invented the world's first handheld cellular phone.

Today Motorola is one of the largest cell phone manufacturers in the world.

And it all started with the car radio.

WHATEVER HAPPENED TO

the two men who installed the first radio in Paul Galvin's car?

Elmer Wavering and William Lear, ended up taking very different paths in life.

Wavering stayed with Motorola. In the 1950's he helped change the automobile experience again when he developed the first automotive alternator, replacing inefficient and unreliable generators. The invention lead to such luxuries as power windows, power seats, and, eventually, air-conditioning.

Lear also continued inventing.

He holds more than 150 patents. Remember eight-track tape players? Lear invented that.

But what he's really famous for are his contributions to the field of aviation. He invented radio direction finders for planes, aided in the invention of the autopilot, designed the first fully automatic aircraft landing system, and in 1963 introduced his most famous invention of all,
the Lear Jet, the world's first mass-produced, affordable business jet (Not bad for a guy who dropped out of school after the eighth grade).

Sometimes it is fun to find out how some of the
many things that we take for granted actually
came into being!


Top of pagePrevious messageNext messageBottom of page Link to this message  By Steve Jelf, Parkerfield KS on Saturday, March 25, 2017 - 11:29 pm:

Progress in the car radio field was rapid. The radio in my mom's 1940 Plymouth was very good.


KFAC was a commercial AM station with a classical format, if you can believe it, and that 1940 car radio introduced me to Beethoven's Third Piano Concerto, a fantastic piece of music then and now.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Mack Cole ---- Earth on Sunday, March 26, 2017 - 12:43 am:

what I can't understand is the newer radios in cars have little to no AM reception. But the old vacuum tube radio in my 66f100 can pick up alot of stations.


Top of pagePrevious messageNext messageBottom of page Link to this message  By john kuehn on Sunday, March 26, 2017 - 03:09 pm:

Steve is that your Mom's 40 Plymouth that you have in the pic? That's neat if it is.

I wish I still had my Fathers 56 Dodge Texas 2dr hardtop he had.
We sold it for 100.00 after he died because he had used it to store cattle feed and block salt in the trunk for many years after he quit driving it.

The floor and trunk area were eaten out of it because of the salt! OH Well!


Top of pagePrevious messageNext messageBottom of page Link to this message  By Norman T. Kling on Sunday, March 26, 2017 - 03:28 pm:

The first car I remember with a radio was a 1939 Plymouth which was owned by my aunt and uncle. We went for a ride with them to hear president Roosevelt give his famous speech after the bombing of Pearl Harbor. We didn't have a working radio at home. I used to have a 1935 Ford and there was a place for a dial and two knobs in the center of the dash. The actual radio was under against the firewall. The antenna was woven inside the top which was then a soft top even though it was a sedan.

I put a radio in my Model A coupe. I put it on the shelf behind the front seat. The speaker was next to my ear. The car was too noisy to hear it anywhere else and of course the dash in a Model A was the gas tank.

In those days all radios were AM. They would pick up noises from the spark plugs and other parts. The Model T jams all AM radios. We made an experiment and turned on an AM radio. A portable radio and it was jammed for over 100 feet from the car when running on magneto and coils.

FM works in a different manor and does not pick up the interference. But AM can be transmitted for longer distances than FM So both types have their good and bad points.
Norm


Top of pagePrevious messageNext messageBottom of page Link to this message  By Eddy Lee Emerson on Sunday, March 26, 2017 - 03:55 pm:

I have a radio that was purchased in 1934 by my uncle, when he and my aunt went on a road trip. The radio was built to sit on the seat cushion between the driver and passenger. Two wires connected it to the ignition switch and the antenna, which was mounted under the running board. When they would stop at a motel for the night, the radio could be taken to the room, where it would also operate from the ac plug in. Ed


Top of pagePrevious messageNext messageBottom of page Link to this message  By Bob Prochko on Sunday, March 26, 2017 - 04:03 pm:

Well, The fantasy world in which Motorola offered the first car radio exists only in their own self-serving corporate history. A firm known as "Radio-Auto Distributors" offered their "Airtone" auto radio set to the commercial market in 1925. All American-Rauland (a major manufacturer of the period) introduced their model 115 5 tube auto radio to the commercial market in 1926. Both of these sets used dry "B" batteries. Transitone introduced a workable car radio with a dynamotor "B" supply in 1928

Galvin's innovation was the vibrator high tension supply. Before the 1930 introduction of the Motorola car radios were very expensive. The development of spark plug suppressor resistors in 1931 combined with the Galvin power supply finally made auto radios practical for use wven while driving.

Radio News published plans for a do-it-yourself auto radio in a 1928 issue. It was based upon a heavily modified Atwater Kent Model 35 radio, a compact six tube set of 1926 vintage with a chassis built upside down in a metal tub. I made one of these up for my 1927 coupe back in the late 1980's. The radio hung upside down from the roof in front of the header panel above the windshield. The set performed pretty well once I installed an Atwater Kent Unisparker ignition system along with resistance ignition wires.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Steve Jelf, Parkerfield KS on Sunday, March 26, 2017 - 04:20 pm:

Yep, that's Mom's Plymouth. Dad drove it to a ball game at Wrigley Field and some kid ran into him and wrecked it. He was OK, but the car went to a junk yard for $15.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Tim Lloid on Sunday, March 26, 2017 - 04:22 pm:

Steve, cool car. Tim


Top of pagePrevious messageNext messageBottom of page Link to this message  By john kuehn on Sunday, March 26, 2017 - 05:08 pm:

Anybody remember the Civil Defense markings on car radios? We had them on the radio that was in the 50 Ford we had as I remember.
They were small round markings with a triangle in the middle.

Wasn't the frequency called Conalrad or something like that?


Top of pagePrevious messageNext messageBottom of page Link to this message  By Fred Dimock, Newfields NH, USA on Sunday, March 26, 2017 - 05:11 pm:

My first car - a 1941 Ford Opera Coupe - had a factory radio.
All I cared about was that it could get WBZ in Boston and WOR in NY - there was also a station in the mid west that we could get at night, but I can't remember what it was.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Dave Frost on Sunday, March 26, 2017 - 06:17 pm:

Bet it was WLS Fred. Had a strong signal.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Bob Prochko on Sunday, March 26, 2017 - 06:28 pm:

Well, Mr. Emerson, your uncle had a General Electric B-52 "convertible" radio. I still have one put back somewhere in storage.


Top of pagePrevious messageNext messageBottom of page Link to this message  By David Stroud on Sunday, March 26, 2017 - 06:31 pm:

Yep John, I think that's what it was called."Dial either 640 or 1240 on your radio dial for emergency information", or something like that. Dave


Top of pagePrevious messageNext messageBottom of page Link to this message  By Bob Prochko on Sunday, March 26, 2017 - 06:32 pm:

Probably WLW in Cincinnati. Between 1932 and 1941 they were a "Super Power" station, radiating a whopping 500,000 watts from their 831ft tall Blaw-Knox tower in Mason, Ohio.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Robert Brough on Sunday, March 26, 2017 - 06:45 pm:

When researching the correct markings for my WWII jeep, the registration number on the hood that you see in all the photos and movies was nine or 10 digits long. If it was followed by a stenciled "S" it meant the vehicles was suppressed for radio interference with a series of filterette boxes under the dash and approximately 17 ground straps to ground everything from the generator to the lights to the frame.
The military soon found that static interference from other or passing vehicles would disrupt communication. Kind of like when you drive under high power tension lines and you car radio turns to mush.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Ken Parker on Sunday, March 26, 2017 - 07:59 pm:

Ford used a Philco in my '35 Cabriolet mounted up under the dash and it hangs over the driver's knees/steering column. The speaker is in the radio console because it's an open car but the rather neat feature is that the spare tire mount and wheel are the antenna.

The radio dial takes the place of the ashtray in the '35 Ford and controls the radio with a set of cables to the console. I just had it repaired but haven't stuck it back in place. You have to be part gymnast to R&R that thing.

The '33/'34 Fords had their radio in the glove box but I don't know about the '32.

Ken in Texas


Top of pagePrevious messageNext messageBottom of page Link to this message  By Norman T. Kling on Sunday, March 26, 2017 - 09:56 pm:

The 1941 Ford had the radio in the dash under the windshield. The antenna went through the roof right over the radio. When it rained and leaked around the antenna, the water would go right into the radio and short things out. Back in the 1950's I spent a night stuck in a flood in the San Joaquin Valley between Fresno and Modesto. All traffic was stopped and water almost up to the floorboards. I couldn't listen to the radio to find out what was happening. Next day we were escorted out by the CHP.
Norm


Top of pagePrevious messageNext messageBottom of page Link to this message  By Bob Prochko on Sunday, March 26, 2017 - 10:21 pm:

I believe that in 1932 Ford offered a Majestic radio (Grigsby-Grunow-Hinds) with a control head mounted to the steering column, powered by a dynamotor under the rear seat. The radio chassis was mounted to the firewall up behind the dash on the passenger side, the loudspeaker was in a metal can (which was much smaller than the radio box) and was usually mounted on the driver's side of the firewall under the dash, next to the steering column.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Bob Prochko on Sunday, March 26, 2017 - 10:29 pm:

I believe that in 1932 Ford offered a Majestic radio (Grigsby-Grunow-Hinds) with a transverse control head mounted to the steering column, powered by a dynamotor under the rear seat. The radio chassis was mounted thru the firewall up behind the dash on the passenger side, the loudspeaker was in a metal can (which was much smaller than the radio box) and was usually mounted on the driver's side of the firewall under the dash, next to the steering column.

I have never seen the earliest of the Majestic sets, but the photo in the service manual lists two different loudspeaker assemblies, one 8" speaker in a large wooden enclosure, and the other a 6" unit in a small metal can. I've seen the metal can units, but these may be intended for aftermarket or remote speaker installations, as the Majestic radio was also sold for installation in other makes of cars


Top of pagePrevious messageNext messageBottom of page Link to this message  By Eddy Lee Emerson on Sunday, March 26, 2017 - 10:29 pm:

Mr. Prochko. yes that is the radio I have. It's amazing to find people with such a variety of information Thank you. Ed


Top of pagePrevious messageNext messageBottom of page Link to this message  By Dennis Plank - Three Way, TN on Sunday, March 26, 2017 - 10:36 pm:

WLW was know as the "nation's station" because of their power. If I remember right, by law back then they had to cut the power back at night because their signal travelled so far. I think about half the country could tune in to listen to the Reds play ball.


Top of pagePrevious messageNext messageBottom of page Link to this message  By paul iverson freeport ill. on Sunday, March 26, 2017 - 11:18 pm:

Bob do you have any pics of the 32 ford G-G used in there ads? that was my dads car!my dad was a 20 year old messinger for grigsby-grunow in 1932 he bought A new 32 V8 ford from a guy that won it in a raffle, that the company put a radio in and used for advertising he got a free radio out of it. we still have the I think it is called the genny motor that went under the rear floor. when he parked in the loop there would be a croud around that car one of the first V8s in chicago and a radio!it used more oil than gas!


Top of pagePrevious messageNext messageBottom of page Link to this message  By John F. Regan on Sunday, March 26, 2017 - 11:24 pm:

To clear up just a few misconceptions. AM radio didn't go as far in distance as FM radio but that had nothing to do with the fact that the modulation was different. It had to do with the frequency or "band" that the AM radio uses which is from around 550 to 1600 KHz while the FM stations were in the 88-100 Mhz region. The higher frequencies that the FM stations were broadcasting on don't travel as far typically for the same amount of power but the FM receiver is almost immune to static noise caused by just about anything that produces a spark somewhere in it. At night the AM stations across the country have to selectively turn down their power to keep their signals from interfering with other stations that during the day are broadcasting on the same frequency. Some stations however are were allowed to broadcast at a much higher power level at night while other stations on that same frequency had to shut down completely so that small towns and farms across the nation would have music at night. These stations are referred to as "clear channel" stations and you may sometimes have heard them refer to themselves during the day by identifying themselves as "WXXX - Clear Channel" since generally the clear channel stations had big towers and had a monopoly on their regular spot on the dial once the sun went down. I think KMOX in St. Louis was a big power station too. Somewhere there is a list of stations and the clear channel stations were clearly indicated.

Even Ham radio operators had to get off the air when there was a Conalrad alert and they had to do it immediately as in seconds. Most of us modified an AM radio tuned to the local radio station and sensed when their carrier signal went to zero power which then sounded an audible alarm in the K9SWN radio shack to also get off the air immediately. I think it was kinda silly in later years and came off something like the "duck and cover" films during the 50's but we all did our part which was part of keeping us all safe.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Corey Walker, Brownsboro TX on Sunday, March 26, 2017 - 11:25 pm:

The radio in my 47 Hudson has a button on the floor that looks like a second dimmer switch that lowers the volume or changes the channel depending on how hard you step on it. Doesn't work but it's there. Owners manual explains it.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Bill Dodd on Sunday, March 26, 2017 - 11:35 pm:

Bill Lear did have a sense of humor. He named his daughter Shanda. :-)

Bill


Top of pagePrevious messageNext messageBottom of page Link to this message  By Steve Jelf, Parkerfield KS on Monday, March 27, 2017 - 04:29 am:

Marvin Miller was on WLW in the thirties with Moon River, a late night poetry program. Speaking at a SPERDVAC meeting about forty years ago he said people near the transmitter could hear the station on barbed wire fences, and even on their glasses and fillings.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Erik Thomas on Monday, March 27, 2017 - 08:29 am:

I have learned more on this thread I ever thought possible. This leads me to think this may be the best "old car" website in the world right now. My sincere thanks to everyone who contributes.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Verne Shirk on Monday, March 27, 2017 - 02:44 pm:

I thought Lear invented the 4 track and later the 8 track came along. I had a Lear 4 track at one time.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Robert G. Hester Jr., Riverview, FL on Monday, March 27, 2017 - 03:14 pm:

Corey, the radio in the 47 Mercury I owned as a teenager had the same thing. It did work.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Sean Butler Huntington Beach, CA on Monday, March 27, 2017 - 05:56 pm:

I have to hop on board with Erik, here. The only thing I will say different is that this IS the best, hands down. It is evident that there is a great interest in history/knowledge here, as well as an enjoyment in sharing it. We can only hope that our successors are following in these footsteps. Well played, mates!


Top of pagePrevious messageNext messageBottom of page Link to this message  By Larry LaPatka- East Tennessee on Monday, March 27, 2017 - 06:45 pm:

To Verne and Eugene,
Bill most certainly invented the 4 track auto tape player before the 8 track. He admired my
self built T bucket back in 1963-64 and gave me one with a great many 4 track tapes including the beach boys. I had it installed under the seat in the Hot Rod and when I sold it I kept it and still have it today. I use it indoors with an old Radio Shack 115V-12V convertor. Still plays and still have the demagnetizer that is also 115 V. Many memories of all. As of matter of fact it is still covered with the stick on vinyl wooden look-a-like material from the 60's. Great memories from growing up in Southern California in the 50's thru 70's, probably some of the greatest times for car lovers of all types. Then got the hell out of there.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Fred Dimock, Newfields NH, USA on Monday, March 27, 2017 - 08:55 pm:

I remember -- it was WOWO in Ft Wayne Indiana

There was also A county station in Wheeling WV that we could get but didn't listen to. WWVA I think.


And can't forget WSM in Nashville, if my girl friend caught me listening to it I would not get a kiss for a week or more..


Top of pagePrevious messageNext messageBottom of page Link to this message  By Steve Jelf, Parkerfield KS on Monday, March 27, 2017 - 09:39 pm:

WSM is still home to the Grand Ole Opry, broadcast live every Saturday night. An AM station broadcasting music is unusual today, and live music is unheard of.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Gary H. White - Sheridan, MI on Monday, March 27, 2017 - 10:13 pm:

As I've heard it Bill Lear's daughter's first name was Crystal. Second Name was Chandra.

My grand dad was self educated on electronics and electrical equipment. My mother told me he was the first person in the Howell, Mi area with a radio in his car. On Saturday nights he would park the car downtown and run the radio. Everyone would gather around to listen to the music, ball games and prize fights.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Lenney Glenn on Monday, March 27, 2017 - 10:16 pm:

Can anyone remember when or if there was a police band just under the AM band? It's been a while ago but I think this was called the VLF (very low frequency ) band.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Harold Schwendeman - Sumner,WA on Tuesday, March 28, 2017 - 04:01 am:

This thread has stirred up memories of things I hadn't thought of for a long, long time! I went thru' high school in Franklin Park, Illinois, listening to WJJD in the garage while working on my '28 Model A Ford Standard Coupe! I just discovered that I "STILL" know every word to the Clark Gasoline commercial song! Must have heard that "jingle" thousands of times on WJJD!

"Clark Super One Hundred Gasoline, thousands say it's best. The largest selling independent gasoline, in the Middle West. Fill up today, you'll know just what we mean. Buy Clark Super One Hundred Gasoline!!!"

Where in the heck did THAT come from??? Hadn't thought of that in many years, and I can't even remember what I had for breakfast yesterday! The human brain is a miraculous (and mysterious) thing,.....especially mine!


Top of pagePrevious messageNext messageBottom of page Link to this message  By Harold Schwendeman - Sumner,WA on Tuesday, March 28, 2017 - 04:15 am:

Eugene,....the very first line you wrote in this thread also "stirs up memories"! You said,....."Seems like cars always had radios, but they didn't."

I remember used car lots in Chicago when I was a kid (born in 1941, so that gives you an idea of the used cars I'm talking about). Used car lots commonly had their best, or "feature cars" in the front row. As you drove buy, you'd see chalked on the windshields, the price, and words like "FIRE & FIDDLE". That meant the car had a radio and heater, Yes,.....HEATER! Young folks today would not believe that many things we now take for granted were not standard equipment on all cars! Many things were "optional" on new cars, especially the "low priced three",....(Ford, Chevrolet & Plymouth) Many cars did not have heater, radio, turn signals, etc. I often think that with so many drivers nowadays too lazy to use their turn signals don't realize how lucky they are to even have turn signals! Imagine sticking you arm out the window to signal a left turn in below zero winter weather! Okay,....enough "reminiscing",.....harold


Top of pagePrevious messageNext messageBottom of page Link to this message  By Harold Schwendeman - Sumner,WA on Tuesday, March 28, 2017 - 04:18 am:

Hmmm,......poofread, poofread! I meant BY,....not "buy"!


Top of pagePrevious messageNext messageBottom of page Link to this message  By Dallas landers on Tuesday, March 28, 2017 - 06:50 am:

What about automatic transmitions Harold? All new firetrucks have auto trans. Because nobody can drive a standard shift.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Mike Kossor - Kenilworth, NJ on Tuesday, March 28, 2017 - 08:07 am:

Lenney, not familiar with a police band just under the AM broadcast band, however, do have a old tube table radio with Police labeled on the dial just above the AM broadcast band. Back in the 1930's or thereabout that was the allocation for the Police band: 1605kHz-1705kHz. This segment is not referred to as the Extended AM broadcast band.

By the way, this is part of the Medium Frequency (MF) band; 300kHz - 3000kHz. For complete listing of the radio frequency bands from Extremely Low Frequency (ELF) to Tremendously High Frequency (TRF) see: https://en.wikipedia.org/wiki/Radio_spectrum

A couple more tit bits about early car radio is that AM refers to the method used to convey information on the radio wave. AM stands for Amplitude Modulation in which the voltage amplitude of the radio wave is varied in direct proportion to the Audio (voice or music) to be sent over the radio wave. AM is one of the easiest methods to create and receive but unfortunately is vulnerable to static from electrical disturbances like lightning and electrical noise from automotive ignitions and brush motors because they all produce energy over a wide frequency range including the MF band which varies in Amplitude which the AM radio detects, amplifies and heard through the speaker because just like the intended AM station it is tuned to.

Frequency Modulation or FM was developed in the late 1920's and early 1930's as the static free solution to auto radios because the information was carried by the radio wave by varying its frequency in direct proportion to the voice or music and electrical noise including that produced by automotive ignitions do not create frequency variations. Recovering the information from FM radio ignores Amplitude variations and thus is immune to Automotive electrical noise. Another interesting historical tid bit about FM radio is the original FM band was 42MHz to 50MHz as proposed and operated by the pioneer of FM, Major Edwin Armstrong. A brilliant pioneer of radio and electronics who was driven to suicide by the legal battles with David Sarnoff of RCA who was very politically connected and lobbied the FCC to move the FM band to the present 88MHz - 108MHz frequency band for supposed technical reasons that ruined Armstrong financially, then refused to pay Armstrong royalties for their use of FM technology. More interesting history here: https://en.wikipedia.org/wiki/Edwin_Howard_Armstrong


Top of pagePrevious messageNext messageBottom of page Link to this message  By Steve Jelf, Parkerfield KS on Tuesday, March 28, 2017 - 08:35 am:

Cereal wars, from when Harold and I were five:

Cream of Wheat is so good to eat that we have it every day,
We sing this song 'cause it makes us strong, and it makes us shout "Hooray!"
It's good for growing children, and grown-ups too, to eat.
For all your family's breakfast, you can't beat Cream of Wheat.
~ Let's Pretend

Shredded Ralston for your breakfast starts your day off shinin' bright;
gives you lots of cowboy energy, with a flavor that's just right.
It's delicious and nutritious, bite-sized and ready to eat.
Take a tip from Tom. Run and tell your mom Shredded Ralston can't be beat.
~ Tom Mix

I dood it!
:-)


Top of pagePrevious messageNext messageBottom of page Link to this message  By paul iverson freeport ill. on Tuesday, March 28, 2017 - 10:05 am:

I was told by my uncle in Chicago in the 20"s the police cars had recivers only tuned in to wgn and police calls cut in to regular broadcasts the police had to go to a call box to answer


Top of pagePrevious messageNext messageBottom of page Link to this message  By Lenney Glenn on Tuesday, March 28, 2017 - 04:24 pm:

Mike,thank you. It has been so many years since I repaired these old radios, I have forgotten a lot of details. Anyone remember these old tubes? 80, 24, 27 5y3,6sq7,etc. Whatever happened to the much touted cold cathode tubes. What about RCA's nuvistor? The semiconductor stampede squashed all advances in vacuum tube technology. I live in the North Carolina mountains and regularly listen to a.m. station WPAQ Mount Airy N.C. that still broadcasts a lot of live mountain music. Time for me to stop rambling and listen.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Bob Prochko on Wednesday, March 29, 2017 - 08:18 pm:

Old tubes? OLD tubes are VT-1, VT-2, 216B, UV201, WD-11. Heck the tubes that you listed are all from light socket sets! ;)

I just spent an afternoon rejuvenating a box of "flat" UV and UX-201A's. Remember those old triodes with the thoriated filaments? The thorium on the surface of the filament could be stripped, and the tubes emission deteriorated. These tubes can be "rejuvenated" two or three times by flash heating the filaments (with no voltage on the plate) with 300% over voltage for about 30 seconds and then "aging" them at 150% voltage for a half-hour or so.


Anyone here collect battery sets (pre-1928 home radio receivers)?


Top of pagePrevious messageNext messageBottom of page Link to this message  By John F. Regan on Wednesday, March 29, 2017 - 08:36 pm:

Bob:

I have an AK-20C battery radio. It is in perfect working order with AK speaker to match. I also have a later AK console radio but it is still a TRF radio. What is interesting on that set is that there is a "local/distant" switch on the front panel to allow you to reduce the RF gain of the first stage so as to prevent strong local stations from distorting by overloading the radio front end. That switch merely turned off the filament of the First RF amplifier tube allowing the signal to simply be coupled through that tube without any gain. What Is interesting in the early battery sets was that they controlled volume to the speaker by adjusting the filament voltage on the tubes. Thus reducing the gain of the set made it play with less volume but also less drain on the battery. The filaments were the largest drain on the setup with most of that power coming from a large 6V wet cell battery that was then recharged. The AK-20C used all 01A tubes as I recall. I also have a complete AK-20 which is a big box radio but with essentially the same circuit as the AK-20C which was the compact version.


Top of pagePrevious messageNext messageBottom of page Link to this message  By David Stroud on Thursday, March 30, 2017 - 05:06 am:

I remember listening to WHB AM from Kansas City in the '60's and '70's here in NW Mo., it had great rock and roll music. This town is located on the western side of large bluffs. A lot of the time, we couldn't get it very well when cruising up and down Main street which is on the lower side of the bluff. It would come in fine when we would go up into the upper part of town or out into the "bottom" to the west. WLS AM in Chicago would come in pretty well after dark most of the time. The best station was KOMA AM in Oklahoma City. It would not come in very well until after the sun set, didn't make any difference what time of year, just when the sun set. If you had it tuned in before sunset, it would kind of "click" just when the sun set, then it came in great. Never did understand why that was. Dave


Top of pagePrevious messageNext messageBottom of page Link to this message  By Mike Garrison - Rice, Minnesota on Thursday, March 30, 2017 - 08:03 am:

Eugene,
The other day a neighbor asked me when they first started putting radios in cars. Now, I think your chances of knowing this guy are slim to none. Can you imagine how intelligent I'm going to seem to this guy when I spout knowledge from your research? Hah! Thank you, thank you.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Mike Kossor - Kenilworth, NJ on Thursday, March 30, 2017 - 08:10 am:

Bob, Yes, I have a 5 tube TRF with 01As also. Akradyne "Built with Akracy" Beautify crafted around 1925 by the Sumbeam company and sold for $75. It features 3 basket weave coils using green silk covered wire. See photos of it here: http://www.radiomuseum.org/r/sunbeam_akradyne_8.html I also have a nice crystal set featuring a galena crystal in a lead cup and cat's whisker to probe it and nice set of Brandies head phones. I received tips on how to find a hot spot on the galena crystal from my Wife's 90 year old Grandmother who recalled using a similar radio back in the day when it was state of the art. It is a wonder how radio ever took off considering the catch 22; you would hear nothing tuning all around the band if you did not have a proper rectifying contact of the cat's whisker to the galena crystal and you would not know you had a proper rectifying contact unless you were tuned to a station. Definitely not a technology for the present day, instant gratification, millennial mindset.

Thanks for the information about rejuvenating 201As, I have a good set in there now but will keep that in mind should they get weak.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Steve Jelf, Parkerfield KS on Thursday, March 30, 2017 - 08:51 am:

I was at Pepperdine in 1963. At the end of the school year Bobby Mathews was going home to Muskogee. A bunch of us piled in Jim Johnson's '58 Chebby to take him home. We got started in the afternoon, and were going through Banning Pass about sundown. Somebody got KOMA on the radio. Taking turns, we drove all night through Arizona, New Mexico, and into west Texas, listening to KOMA all the way until sunup. The hits in heavy rotation were Sweet Dreams of You (Patsy Cline), Sukiyaki (Kyu Sakamoto), and Tie Me Kangaroo Down, Sport (Rolf Harris). The station later went through several format changes and eventually descended into talk radio and became KOKC.


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