• 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

Can AM reception in car radios be improved?

My old 90s Ford had great AM reception.....as long as the engine wasn't running.
I've said this before but my first car in 1974 [1962 Chevy II Nova] had the best damn AM radio of any car I had. I picked up KOA out of Denver, 2 stations out of California [wish I could remember their call letters]; one from LA, one from SF while sitting in my driveway in NE Ohio and very often a lot of stations from out west, from Florida to Maine and lots of stations out of Canada. If I had been smart, I should have yanked that radio out when I got rid of the car.
 
you can get AM radios in cars back to where they were as far as selectivity, sensitivity, alt channel rejection and a good old fashioned fender ( or quarter panel) mounted antenna, and shield the crap out of it from all the electronic modules in the car ( fuel injection, BCM. ECM, ABS, lighting, etc etc etc) but the other issue is the "noise floor" aka electric pollution from all sorts of lighting devices, utility pole mounted electronics, crappy consumer power supplies, and everything else that is tossing spurious radiation out onto the universe.

Digital AM would resolve a good part of those problems
 
you can get AM radios in cars back to where they were as far as selectivity, sensitivity, alt channel rejection and a good old fashioned fender ( or quarter panel) mounted antenna, and shield the crap out of it from all the electronic modules in the car ( fuel injection, BCM. ECM, ABS, lighting, etc etc etc) but the other issue is the "noise floor" aka electric pollution from all sorts of lighting devices, utility pole mounted electronics, crappy consumer power supplies, and everything else that is tossing spurious radiation out onto the universe.

Digital AM would resolve a good part of those problems
In 1936, Maj. Armstrong invented something that solves all of those problems. It's a shame that it didn't get off the ground. :rolleyes:
 
If it has sheet metal or metal screen on all sides, then it is a Faraday Cage.

Yes, the trunk is a faraday cage, your entire car is, to an extent, but that doesn't mean that signals can't necessarily get through, especially local ones. You will notice a signal drop in the trunk, though.
A trunk would not have it on all sides necessarily which is why it is not a real Faraday Cage although it may act like one. The trunk lids do not always extend far enough which allows signal to pass through the rear deck/window or other spots where the metal is not one piece.

By the way, if the inside of car was a Faraday cage, then cell phone use would not work as reliably as it generally does.
 
A trunk would not have it on all sides necessarily which is why it is not a real Faraday Cage although it may act like one. The trunk lids do not always extend far enough which allows signal to pass through the rear deck/window or other spots where the metal is not one piece.
The metal mesh in the seat back works as a cage wall. Many of us have used wire mesh or screen under wallboard and above ceilings and below floor tile or in the concrete to create a cage around a studio that is at the transmitter site.
By the way, if the inside of car was a Faraday cage, then cell phone use would not work as reliably as it generally does.
The windows let signals in and out. If you move your phone or tablet down to your lap and watch the signal nearly disappear below window level.
 
That's been more or less tried with HD Radio but it never took off compared to the FM side.
I'm talking an across the board wipe out of AM and go to digital, like WSRO is testing in the Boston area

It sounds fantastic and covers distance well

The only problem is will any market be able to support a proliferation of stations on a Digital band?

The economy is having trouble sustaining what is already on the air, if a new band was carved out of the 540 to 1700 space that exists now could it be profitable?
 
I'm talking an across the board wipe out of AM and go to digital, like WSRO is testing in the Boston area

It sounds fantastic and covers distance well

The only problem is will any market be able to support a proliferation of stations on a Digital band?

The economy is having trouble sustaining what is already on the air, if a new band was carved out of the 540 to 1700 space that exists now could it be profitable?
It seems unlikely given how AM is just not as popular as it was maybe fifty years ago before FM took over and now you have other options like streaming, satellite etc.

However, your example of WSRO is still HD Radio. There are simulcasts on other AM/FM frequencies and the analog signal is not being used for 650 but it's still the same frequency in the same AM band. There are not a lot of listeners with HD tuners except in cars but maybe they're thinking that will work for them:

 
The windshield antennas have been around for years in many cars as I recall back to at least the 1980's.

They sucked in the 80s too. Poor reception and lots of static, just like today's compromise antennas.

The vertical whip is/was the best car antenna. 1/4 wavelength for great FM reception, and they do the best job with AM reception.

All the automakers' attempts to make the antenna disappear over the decades have only proven that physics works better than smoke & mirrors with signal amplifiers.
 
In 1936, Maj. Armstrong invented something that solves all of those problems. It's a shame that it didn't get off the ground. :rolleyes:
Yeah, but you gotta remember back in "the good old days" FM was the domain of classical/"Beautiful Music/Easy Listening", jazz or foreign language/music shows. I can recall a number of beautiful music/easy listening stations in the early 70s around the Cleveland area--WAEZ, WDBN, WXEN and Ia few others whose call letters I can't remember. My second car I had [66 Rambler Ambassador] had an AM/FM radio but the FM could only pick up WDBN....just what every teenage male wanted to listen to! Sure you had the outliers, WMMS, WNCR and [I think, but I may be wrong] WNCO. Wasn't until around 1974/75 that FM began to take off and AM tried to compete by changing formats as often as a parent changes a baby's diaper and finally gave up and switching to news/talk/sports. Surprisingly, I am hearing more music on AM stations nowadays, I'm assuming it's because a lot of them now have FM translators.
 
I have a 2018 Mazda 6. The AM reception is fine. No engine noise whatsoever. I'm about 15 miles south of Orlando and some Miami AM's come pretty well during the daytime (ie WQAM 560, WIOD 610 and WINZ 940). The antenna is a bunch of wires in the back window.
 
I'd long heard that engineers used to use Chrysler car radios at the xmtr shack for monitoring. Just happens I was bequeathed my late Folks; car, a red 2008 Sebring that still purrs along. It's AM and FM reception is excellent -- and even better than the GE Superadio 2 with the engine turned off.
Somewhere in the confusion here is the AM-FM-cassette radio from a 1992 Plymouth Acclaim. I had it hooked up to wall current in ths house for a while ; again, splended reception.
Some of those used antique junkyards in your area still might have a few of these on a shelf. Installation into a more modern car no doubt will pose some problems, and with me still uncertain as to which end of hot soldering pen to hold I'm not about to try anything that reckless. That form of customization, though, might be an intriguing pursuit for some DXers here.
 
Nearly all stations had modulation monitors at their transmitter sites and used those for accurate monitoring.
 
Yeah, but you gotta remember back in "the good old days" FM was the domain of classical/"Beautiful Music/Easy Listening", jazz or foreign language/music shows. I can recall a number of beautiful music/easy listening stations in the early 70s around the Cleveland area--WAEZ, WDBN, WXEN and Ia few others whose call letters I can't remember. My second car I had [66 Rambler Ambassador] had an AM/FM radio but the FM could only pick up WDBN....just what every teenage male wanted to listen to!
When I was around 13 WDBN was my favorite station. I had about 3 hours of homework each night, and it was great company while doing those tasks with its Beautiful Music format, even though I worked part time at the all jazz station, WCUY. The only problem was that in 1960 or so FM radios did not have "working" AFC, so in the course of an evening it would drift of frequency and need re-tuning all the time.
Sure you had the outliers, WMMS, WNCR and [I think, but I may be wrong] WNCO. Wasn't until around 1974/75 that FM began to take off
FM started "taking off" in the very late 60's when the FCC required AM/FM combos to stop simulcasting most of the time.

WMMS was hardly an outlier... it was for decades the #1 station in Cleveland, starting its rise in 1972 and reaching #1 in 1975/76. WDOK and WQAL were the #1 and 2 stations by around 1972, and WDOK had been #1 or #2 since '69 or '70

By 1976, half of all Cleveland listening was to FM.
 
Last edited:
They sucked in the 80s too. Poor reception and lots of static, just like today's compromise antennas.

The vertical whip is/was the best car antenna. 1/4 wavelength for great FM reception, and they do the best job with AM reception.

All the automakers' attempts to make the antenna disappear over the decades have only proven that physics works better than smoke & mirrors with signal amplifiers.
The vertical whips were better than the windshield antennas at that time but today's are not the same. Also, there is way more interference from various sources like the car itself or others like cell towers which can interfere with weak stations. There have been articles on AM stations not being maintained as well as they were when AM was king so there are just too many factors in the mix.
 
Yeah, but you gotta remember back in "the good old days" FM was the domain of classical/"Beautiful Music/Easy Listening", jazz or foreign language/music shows. I can recall a number of beautiful music/easy listening stations in the early 70s around the Cleveland area--WAEZ, WDBN, WXEN and Ia few others whose call letters I can't remember. My second car I had [66 Rambler Ambassador] had an AM/FM radio but the FM could only pick up WDBN....just what every teenage male wanted to listen to! Sure you had the outliers, WMMS, WNCR and [I think, but I may be wrong] WNCO. Wasn't until around 1974/75 that FM began to take off and AM tried to compete by changing formats as often as a parent changes a baby's diaper and finally gave up and switching to news/talk/sports. Surprisingly, I am hearing more music on AM stations nowadays, I'm assuming it's because a lot of them now have FM translators.
WDOK and WQAL also had the beautiful music formats. WDOK used to mention is was "The Sound of the Western Reserve." You would hear those stations in doctor's offices and similar waiting areas. WNCR was rock which later became WKSW for a time with beautiful music but just for a few years before going country. I remember WIXY 1260AM being a top station for some time before FM became the popular choice.
 
When I was around 13 WDBN was my favorite station. I had about 3 hours of homework each night, and it was great company while doing those tasks with its Beautiful Music format, even though I worked part time at the all jazz station, WCUY. The only problem was that in 1960 or so FM radios did not have "working" AFC, so in the course of an evening it would drift of frequency and need re-tuning all the time.
And if the AFC worked well, but the front end still drifted far enough - now and then it might jump to the next adjacent station.
 
The vertical whips were better than the windshield antennas at that time but today's are not the same. Also, there is way more interference from various sources like the car itself or others like cell towers which can interfere with weak stations. There have been articles on AM stations not being maintained as well as they were when AM was king so there are just too many factors in the mix.
Light rail vehicles in many cities are another nasty source of noise. Commonly running on 600 vdc from the overhead power line (or 3rd rail), the old styles used large switched resistors to control speed - now they mostly have noisy solid state switching power supplies making the overhead power line a near-perfect antenna.
 
Most newer cars use Software Defined Radios (SRD). They are cheaper to make and can be programmed for just about any frequency band and reception mode. Therefore, the same radio can be used in cars no mater where they are going. As an old friend in IT once said: "it's simply a mater of programming."

That said, it is disappointing that 1) they narrow the bandwidth of AM to hide, over come, eliminate noisy. No matter how strong the signal, the station sounds like crap. 2) They don't allow the end user more control of a receiver that can do amazing things.
 
Many AM receivers that I have had have been optimized for midrange vocal response with no lows or highs.
 
Status
This thread has been closed due to inactivity. You can create a new thread to discuss this topic.


Back
Top Bottom