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Seeing the post made by Rock957 reminded me of my on air monitor.
I have a 1989 Ford Bronco Radio serving as the over the air monitor for my stations.
The radio is wired directly to the Broadcast Electronics board’s air monitor input.
The power supply comes from an old Motorola bank charger which supplies the needed 12 volts DC power.
The radio works well even with no attached antenna thanks to the proximity of the transmitters, it tunes the entire FM band but only goes 530-1600 on the AM band. The Display is nearly burned out but it still pumps out fantastic audio.
Another project I had with a car stereo involves an aftermarket audiovox mounted into an old PC case that the Full Power station uses for Live Remotes.
Total posts : 45366Mighty1650,
You are doing the same thing I plan on doing with the old but very capable Chrysler RAZ car stereo I just took out of my 2000 Grand Cherokee. All the functions still er function and it will be nice to have AM Stereo in the house instead of sitting out in the Jeep listening to the radio at 3 AM lol
I run a Behringer UB1202 mixer so no way to mute the radio if i go live, i can always turn it down before opening a mic on air. Now that the new stereo is in the car I should have time to find a box to mount this old radio in.
Total posts : 45366It makes sense to use a car radio for in-home or in-studio listening. It is by far the most sensitive of easily available radios. The only way you’re going to better the sensitivity is to get a high end MacIntosh tuner (and it’s a lot more expensive than a good car radio).
The only thing is you’ll need a very good, regulated power supply to avoid hum (filtering is one of the things you don’t need when running off a battery). Either that, or run it off a battery yourself.
Total posts : 45366I’ve used car stereos for mostly FM DX’ing for years. Some have been just given to me. Just rework that Motorola connector with an “F” connector pigtail, a decent 13.8VDC power supply (2 amp minimum.), and either decent speakers, or a resistor network to drop audio power to audio line level to feed a stereo amp, and there ya go. Yeah, you can make a decent AM receiver that was as well, since the RX (Receiver), specs for sensitivity and adjacent channel rejection will usually exceed that of most portable and home tuners. And, if you have car stereos given to you, that price is right.
Total posts : 45366I’ve never had much luck getting AM to work well on a car radio. FM has always been wonderful, it seems the radios really need that car body for AM reception or a really long wire.
Total posts : 45366I’m thinking a compact loop would do the job with a car AM tuner… it could be built on a swivel for directional aim.
Total posts : 45366Used to have a GM car radio(in the 70s) that I brought in the house and ran off 2 rectangular lantern batteries(6 volts each) and played it through a small guitar amp. Was fantastic, a true super radio and the antenna is unidirectional…an added plus.
If only people had better radios in their homes we would have better coverage with our small signals.
Mark
Total posts : 45366Mark gives the idea we have been waiting for!
We buy up a batch of used car radios, find a safe, qick, inexpensive way to add power supplies, and we give the radios to everyone within range and totally arm the audience so they are ready to listen!
Total posts : 45366I am going to be transmitting C-Quam AM Stereo soon as my friend is going to add it to a Ramsey AM-25 for me. Now with car Radio’s put inside a boombox case and connected to a loop antenna the station should go quite far. And for FM you’d add a telescopic 6-8 ft whip antenna. You would need 8 rechargeable D batteries to make it portable and with some good 6 inch cones for the main and a 2-3 inch tweeters you could be rocking and able to DX on FM as well as AM and receive C-Quam Stereo too.
I did read somewhere that the FCC was going to make it mandatory for any receiver that receives FM stereo to cover AM stereo as well. If this is the case than we have some potential to get listeners.
There are some Radio’s capable of AM Stereo and are portable. One made by Sony costs $40 and that would be affordable to listeners too. The only thing you’ll have a problem is with the Hard sell tactic you’ll have to deploy to get them to buy the Radio’s.
Total posts : 45366Not sure how up to date this is: http://meduci.com/stations.html
Total posts : 45366I can verify at least one entry is up to date, at least as of a few months ago!
I spoke with the owner of AM 1300 back in April. I ran into him at the Belton hamfest. He had quite a story as to how he came into ownership of the station when it was either dark or nearly dark. Apparently he salvaged the stereo components from a friend that was running a talk radio station. He claims to be very profitable now. I hope so!
Total posts : 45366You’re going to need more than 8 D batteries to power a car radio, particularly if you crank up the built-in amplifier (they weren’t designed to conserve power). It is a good idea – back in my youth (I won’t say how long ago that was), when I didn’t have any money, an inexpensive car radio powered by a Radio Shack 5 amp power supply was my stereo for quite a while.
Total posts : 45366TheLegacy said: “And for FM you’d add a telescopic 6-8 ft whip antenna.”
Mr. Ding Dong said: “Many FM car radios are optimized for a 31 inch vertical antenna. That is nearly a 1/4 wave in the middle of the FM broadcast band. An antenna 6-8 feet long would most likely perform worse.”
Total posts : 45366I agree with Mr. Ding Dong. Longer antennas don’t necessarily work better on FM, as the 1/4 wave length is so short (unlike AM, where anything under 45 meters is too short, and lengthening it up to that point is helpful).
Total posts : 45366The topic here of using a car radio as a monitor is just an excuse for me to reminisce about days gone by.
Back in my youth, junior high and beyond, I wanted a nice radio to listen to rock and roll in all the glorious fidelity it offered on AM. Being funds limited, I visited a local garage/scrap yard and asked about getting a car radio. The owner told me to search his back lot and if I found something to borrow his tools to rip it out and I could carry it home if I swept his garage. I not only swept but carried out the trash and he and I were very happy with the deal as I trotted the half mile back home with my treasure, an Oldsmobile vacuum tube set with a wonderful vibrator chopper to run its transformer on AC derived from the DC battery circuit.
Back in the basement lab, I pulled the vibrator and shorted across the connections so I could power the radio with a transformer salvaged from a junk TV which had a 6.3 volt winding with plenty of amps behind it. The 12 inch speaker used was in a gutted early 50s TV cabinet in the corner of my lab space. With a junk salvaged whip antenna connected it worked beautifully. I added a junk box DM70 magic eye tube as a tuning indicator and for a total cost of zero I had a great sounding AM setup.
A teenybopper such as I was doesn’t always think of unintended consequences, such as my lab was below my parent’s bedroom and quiet hours began fairly early in the evening, nonetheless, hours of enjoyment ensued. The radio and speaker are here in storage and many months ago I brought it to the bench to try it but it no longer works. The problem is the capacitors are all leaky and the effort to recap to get it working is just not a priority, so the fond memories will have to suffice.
Neil
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