New FM Antenna?

[Jaceutah]

Looking for suggestions on how to change out our 18 year old AM/FM antenna to something new that may operate better.


Quite a while ago, I found an old thread that showed a Monaco roof that looked like ours, and the respondents indicated the antenna with the spiral on the Driver’s Side is for the AM/FM radio.


Please refer to the attached photo I took today.


After doing some research yesterday, some information seems to say that this is actually the old CB antenna. The guy who helped me switch out the old radio to a new 2 DIN Kenwood told me it was the radio antenna, not the CB (which he took out).


I am seeking a definitive answer on this.


And… I am hoping someone more techie than I am can help me find an awesome upgrade for my antenna to help the range and reception for my new radio.


The antenna is so tall up on the motorhome, shouldn’t we get better reception than what we get in the car below?


Any suggestions are welcome!

[ByeTheWay]

A CB antenna would be a lot longer than what I'm seeing in the picture. Transmitting antennas have to be tuned to a specific length to keep from harming the transmitter. (Like a ham radio)



Therefore I believe what you have is a radio antenna. It should be plenty high for good reception.

[Jaceutah]

Originally Posted by ByeTheWay

A CB antenna would be a lot longer than what I'm seeing in the picture. Transmitting antennas have to be tuned to a specific length to keep from harming the transmitter. (Like a ham radio)



Therefore I believe what you have is a radio antenna. It should be plenty high for good reception.

Thank you!


So no need for an upgrade?

I wish there was a way to boost the reception for our FM radio.... it is weak.

[CountryB]

My CB antenna is about 24 inches in height. I don't think you can determine if the antenna is for the radio or CB by height alone.

If the CB works, try unscrewing/removing the antenna mast and then see if the CB still works. If it stops working you will know that is the CB antenna in your photo.

You could test your radio by running a new antenna from the radio to the roof (just running cable out the window) for testing. You can get a radio antenna with about 6 foot of cable at the auto parts store for under $20.

[tinkerreknit]

I'd check the connections first. That's where I've seen the most trouble. They often go bad or shake loose. I had one similar to your picture, and there was a wire inside the spring that wasn't making a connection. It's hard to tell much by looking at the picture. My guess is that it is for AM/FM, unless there is a coil on up the antenna. That would be obvious. Lots of FM antennas are around 19", but there are different ways of making them that determine the length. If it is CB, it will still receive AM and FM. There are 12 volt antenna boosters available pretty cheap (Amazon, etc.) but you have to supply power somehow. I second the temporary new antenna trial too. That's easy to do.

[ByeTheWay]

Frequencies used for CB are in the 11 meter range. CB antennas are wound around a fiberglass rod to accommodate the length of wire needed a screw is placed on the end of the antenna to "tune" the antenna using a SWR meter.

Your picture shows a wire antenna similar to those for a am/fm radio. The base spring is just a spring. I don't see wire coiled for the proper length.

A 10 meter ham transmitter antenna for a full wave is 10 meters in length. A meter is longer than a yard. So the antenna would be longer than 30'. Even a quarter wave antenna would be 7.5' long.


I use Spotify for music. As a member $10/month I can download all the music I wish to play instead of relying on an FM signal.

[Mark_K5LXP]

My money is that the antenna in the photo is for CB. The three bolt fender style mount and solid whip/spring suggest to me it's CB. Most AM/FM whips and mounts aren't that beefy. One clue would be to access the area behind it and see if there's a tuning network there - a small box or cylinder. Any short whip for CB will require some sort of tuner to resonate the whip for those frequencies. An AM/FM antenna wouldn't have one, just the coax feed. Another clue would be whether there's a molded coil in the middle of the whip. The photo doesn't show the entirety of the whip.

Something you could try is to tune in a weak station on the radio, then remove the spring and whip from the antenna mount. If this is the AM/FM antenna, signals will be noticeably worse with the whip removed. Likewise if you have a CB installed, signals and noise will diminish if this is the whip for that and you remove it.

There were combiner gadgets you could buy that "split" a single antenna into an AM/FM and CB connection, so maybe that's what's going on here if there's no other rooftop antennas visible. Easier said than done is to trace out where this thing terminates and eliminate all doubt. Did RV's ever employ glass antennas? Guessing not, windshields are expensive enough. On my RV the AM/FM is a short rubber duck and it sort of works, but I find it a bit lacking in the hinterlands. Since the winegard wing antenna covers the FM band my next test is to try a splitter off of that.

Mark B.
Albuquerque, NM

[Ivylog]

CB antennae

[Roadmiester]

I feel your pain. Our radio reception sucks. Had a shop check it out but they were of no help. So we have a new radio, but can't get a station to save our lives. Not sure where to go from here, was hoping there would be some suggestions for a good antenna.

Roadmiester
09 Dynasty Regal RV

[nvs4602]

What you have is a roof mount radio antenna like this one.
https://www.etrailer.com/RV-Antennas...n/44US01R.html

Just do a search for roof mount car radio antenna and pick the one with the best reviews.

What happens with old antennas like yours is the ground at the point of mounting gets corroded over time. And having a good ground is a must.
Just hooking up an antenna and sticking it outside won't work because it has to be grounded to the chassis. Look at the antenna i posted above it has a separate ground wire that goes to the chassis ground. Which you will need since your coach is fiberglass.

Hope this helps.

[153stars]

I have two of same antenna,one on rear bedroom for radio cassette there is no CB back there it's AM/FM.
My old TT had a cheapish no name analog car stereo with a distant DX /LOC local button . aluminium roof similar roof mounted unit. I could get a ridiculous amount of stations on that thing on DX .

[Jaceutah]

Originally Posted by CountryB

My CB antenna is about 24 inches in height. I don't think you can determine if the antenna is for the radio or CB by height alone.

If the CB works, try unscrewing/removing the antenna mast and then see if the CB still works. If it stops working you will know that is the CB antenna in your photo.

You could test your radio by running a new antenna from the radio to the roof (just running cable out the window) for testing. You can get a radio antenna with about 6 foot of cable at the auto parts store for under $20.

Thank you, Mike. I may just do it that way. I was hoping it wouldn't be too costly, but that antenna that nvs4602 suggested looks nice and like a direct replacement.

[Jaceutah]

Originally Posted by tinkerreknit

I'd check the connections first. That's where I've seen the most trouble. They often go bad or shake loose. I had one similar to your picture, and there was a wire inside the spring that wasn't making a connection. It's hard to tell much by looking at the picture. My guess is that it is for AM/FM, unless there is a coil on up the antenna. That would be obvious. Lots of FM antennas are around 19", but there are different ways of making them that determine the length. If it is CB, it will still receive AM and FM. There are 12 volt antenna boosters available pretty cheap (Amazon, etc.) but you have to supply power somehow. I second the temporary new antenna trial too. That's easy to do.

I am going to have to unscrew the base from the body to see if something is loose in there. I am dreading that because I don't want to mess up the paint.



There is no coil on the antenna.


That Jensen that nvs4602 suggested looks like a direct replacement...

[Jaceutah]

Originally Posted by ByeTheWay

Frequencies used for CB are in the 11 meter range. CB antennas are wound around a fiberglass rod to accommodate the length of wire needed a screw is placed on the end of the antenna to "tune" the antenna using a SWR meter.

Your picture shows a wire antenna similar to those for a am/fm radio. The base spring is just a spring. I don't see wire coiled for the proper length.

A 10 meter ham transmitter antenna for a full wave is 10 meters in length. A meter is longer than a yard. So the antenna would be longer than 30'. Even a quarter wave antenna would be 7.5' long.


I use Spotify for music. As a member $10/month I can download all the music I wish to play instead of relying on an FM signal.

Thank you for this input!