radio antenna unscrewed
Imagine my surprise when I can off the track yesterday and found only a little threaded nubbin where my radio antenna had once been.
All the wires are still connected. It just looks like the mast unscrewed from the "wire base".
Anyone ever heard of this and does anyone know who might sell the replacement?
This happened to me last season. Never noticed it in the race or until I got out of the car. It is now on my checklist to make sure it's tight every race.
You'll need to match the frequency of your antenna to your radio band but lots of choices on Amazon really.
Just search for an NMO antenna if you have the 1/4 inch end or Motorola antenna will find it as well.
Sent from my SM-G955W using Tapatalk
So all I need to find is the right antenna whip for the frequency of my radio. It looks like a lot of them do not have cables on them. Am I correct to assume that these should screw on to my base?
And thanks so much for the response.
Yes the antenna just screws on. Post a picture of the base.
The formula for the starting length, in feet, of a quarter wave vertical antenna is 234 divided by the frequency in Megahertz.
That will get you in the ball park. One then adjusts the length for minimum SWR (standing wave ratio) or more elegant methods that aren't needed here. Generally the formula length is good enough for our purposes.
This presumes there are no loading coils or matching devices in the antenna base or transmission line; which happens if the manufacturer wants to use a half or five eight's wavelength for gain.. How long was the original antenna and what radio frequency are you using?
Have fun. Jim (building antennas since 1955)
Otherwise call the radio manufacturer or distributor.
Very common for them to loosen
Or...
You might try asking the guy who finished behind you to check the screen on his radiator and have him mail it back to you.
Lola: When four springs just aren't enough.
but dont use loctite. After tightening, put a fillet of epoxy or RTV across the joint (and not JB weld).
Will have to check frequency. Have it written on back of radios. Antenna whip was about 8 inches. But is is just one that I picked up in a box of stuff on Apex a while ago. No clue if it was correct length or not. All I know is that it improve performance compared to a Radio Shack antenna for a 2 way handheld radio that I had used for years.
Will have to check frequency. Have it written on back of radios. Antenna whip was about 8 inches. But is is just one that I picked up in a box of stuff on Apex a while ago. No clue if it was correct length or not. All I know is that it improve performance compared to a Radio Shack antenna for a 2 way handheld radio that I had used for years.
Biggest issue with RS antenna was despite our best efforts could not get rid of what sounded like ignition noise until we moved it to the front of the side pod.
OOPS thought I was editing original.
468.866
Vertical mobile antennas typically have a resonant frequency at a length of 1/4 or 5/8 wavelengths. 469 MHz divided into 234 gives an approximate antenna length of .5 feet or six inches, for a quarter wavelength. I suspect what you need is not just the antenna rod but also the screw connection at the bottom.
Knowing the above you can call a supply house, like Ham Radio Outlet, www.hamradiooutlet.com or one of the other suppliers under the search, Ham Radio Supply. Ask for someone who can talk to you about a commercial antenna for 469 Megahertz. Describe your problem and requirements. Don't be discouraged if you get a clerk that doesn't know what you are talking about. Ask to talk to one of the hams that runs UHF.
They will need to know the type of connection the antenna attaches to: Whether it is male or female, the outside dimension and what t looks like.. Ask how to find it on their web site.
Even if you have to buy antenna, mount and coax they are fairly cheap compared to car parts, Ha.
Good hunting. If you are totally unsuccessful PM me
Jim
the right link is https://www.hamradio.com/
the outlet got me everywhere but where I wanted to go. But it was an interesting adventure. Thanks so much for the tip Jim.
Another search: "Commercial UHF Mobile Radio Antenna" will give you options to look at.
Umm...why not call (Racing Electronics, Racing Radios, Speedcom, or whatever) and ask what part you need based in your radios (VHF, UHF, etc.) and what’s left of your antenna? I suspect you, or somebody got the antenna from one of those companies in the first place. Seems pretty simple to me or am I missing something...
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In memory of Joe Stimola and Glenn Phillips
Bob, Good suggestion and an excellent approach. I'm cheap and would rather pay $15 to $30 than $150 for equivalent performance. Granted antennas by those respected vendors may be designed for our cars and may be better in some circumstances, but a commercial band antenna is just a commercial band antenna. For example the Racing Radios antenna with a built in ground plane would likely have better performance than a commercial antenna with a home made ground plane. As I said, it is a good suggestion and excellent approach.
Have fun today. JIm
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