Adjustable car radio antenna used as a scanner antenna

[vincent714028]

I have a 98 Honda Civic that has a manually adjustable radio antenna that extends out about 18" or can be reduced all the way back. I am considering using this for VHF Hi and 800Mhz. Does this sound like a good idea? What are your thoughts?

The signal needs to be split for the radio and for the scanner. This could mean I need to use a splitter. I thought an active amplified splitter would eliminate the inherent loss of the splitter.

Or could I create a permanent "Y" coaxial cable by splicing a new section into the original cable? Outside interference might be eliminated by using aluminum paint (paint with metal particles) or other means.

Any ideas, or assistance is appreciated.

 

[Al42]

I have a 98 Honda Civic that has a manually adjustable radio antenna that extends out about 18" or can be reduced all the way back. I am considering using this for VHF Hi and 800Mhz. Does this sound like a good idea? What are your thoughts?

The cable is super-high-loss at UHF and above.

The signal needs to be split for the radio and for the scanner. This could mean I need to use a splitter. I thought an active amplified splitter would eliminate the inherent loss of the splitter.

I've never heard of an active splitter that had a car radio (AM & FM broadcast bands) port. A few people here have tried splitters for car radios - I can't recall any of them being happy with them.

Or could I create a permanent "Y" coaxial cable by splicing a new section into the original cable?

Splicing coax is a bad idea at best. Splicing the type of cable used in car radio antennas is an even worse idea. It's basically an air core.

Outside interference might be eliminated by using aluminum paint (paint with metal particles) or other means.

"Aluminum" paint is now carrier and tint - no more turps and powder. They haven't made that in at least 40 years. There are better ways to shield a coax splice, but why bother - the leakage from the splice is likely to be the only signal you get. Oh, and aluminum paint never really shielded much, which is why everyone paid 10 times as much for silver "paint". At least it worked.

Best idea - get an antenna for the scanner.

 

[RISC777]

Am /fm

Al,

Tired, a bit lazy, so do you mind reminding me what range AM and FM radio are in?

Thanks

"I've never heard of an active splitter that had a car radio (AM & FM broadcast bands) port. A few people here have tried splitters for car radios - I can't recall any of them being happy with them."

 

[vincent714028]

What is air core coax?

I've never heard of air core coax. How is it different from regular coax?

My grandfather recommended the aluminum paint. I hadn't heard of it either so 40 years makes sense.

What if I used a GRE signal amplifier? The $60 dollar one from their website? Adding different connectors wouldn't be a problem. It should even improve my am/fm reception.

 

[AZScanner]

What if I used a GRE signal amplifier? The $60 dollar one from their website? Adding different connectors wouldn't be a problem. It should even improve my am/fm reception.

OK. Let me see if I can give you a good analogy here....

Suppose you want to collect some water from a faucet. Most people recommend buckets for this, but you only have a sponge. Now think logically about it. Is the sponge going to hold the water coming out of the faucet? Sure, it'll hold some, but no where near as much as a bucket would right?

OK, now follow me on this. What if you put a high pressure nozzle on the faucet and then use the sponge? Will that make it hold as much water as a bucket?

Answer that and you'll have your answer on the amplifier too.

EDIT: I should also add that for $60 you can get a dandy little mobile antenna that will work FAR better than any stock AM/FM antenna and amplifier combo. If you're going to spend the money, spend it on something that is proven to work 100% of the time.

-AZ

 

[Al42]

Tired, a bit lazy, so do you mind reminding me what range AM and FM radio are in?

Seriously?

AM - 550 KHz - 1750 KHz
FM - 88 MHz - 108 MHz

I've never heard of air core coax. How is it different from regular coax?

It has a very thin piece of plastic thread wound around the center conductor to insulate it from the shield - but the contact points are tiny, so the loss is lower. These days we have much better ways of building low-loss cable, but tradition ...

What if I used a GRE signal amplifier? The $60 dollar one from their website? Adding different connectors wouldn't be a problem. It should even improve my am/fm reception.

Your FM reception, maybe, but your AM reception would disappear. And, since your noise level would go way up, you'd probably be better off just using the rubber ducky inside the car.

 

[kb2vxa]

Hi guys,

Never mind all the confusion, to put it simply the whole thing is a bad idea. If you want proper reception use a proper antenna. That's what the engineers had in mind when they chose the antenna for the car radio, leave it alone and use a scanner antenna for the scanner, those engineers got it right too.