Multiple antennas on glass

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PrivatelyJeff

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I'm fairly new to all this so forgive my ignorance.

I just got a new car (2011 Ford Fiesta) and I'm looking to outfit it with multiple types of radio gear (scanner, ham radio and CB) and I would like to use glass mounted antennas because I want to not drill holes in my car and I don't need the maximum power I could get with other types. I know these types of antennas will work on my car because I've seen them used in a fairly functional fashion.

My question is, can all these antennas be mounted on the same rear window without them interfering with each other?
 

emtprt

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I'm fairly new to all this so forgive my ignorance.

I just got a new car (2011 Ford Fiesta) and I'm looking to outfit it with multiple types of radio gear (scanner, ham radio and CB) and I would like to use glass mounted antennas because I want to not drill holes in my car and I don't need the maximum power I could get with other types. I know these types of antennas will work on my car because I've seen them used in a fairly functional fashion.

My question is, can all these antennas be mounted on the same rear window without them interfering with each other?
I have used VHF,UHF, and 800 glass mount antennas without any issues. You need to stay clear of the rear defroster and be aware that some tints affect antenna performance.

I never had good luck with glass mount scanner antennas but I recently tried a Tram one that seems to work well.

FYI Lower frequencies do not seem to work well when a glass mount antenna is used. I do not believe there are any commercial glass mount antennas produced anymore. I would avoid the CB style due to the lack of a good ground plane.

You get what you pay for and don't expect the same performance that a hole, trunk mount or magmount will give you.

Mark


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mmckenna

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You need appropriate separation between the antennas. Rule of thumb seems to vary depending on who's thumb you are looking at. 1/4 wave length is usually a good idea.
Issue is that if the antennas are close enough the antennas doing the transmitting can couple to the others and end up with too much RF energy reaching the soft expensive bits inside your radios. This can result in something as simple as receiver desense (receiver will get overloaded and stop receiving while you are transmitting with another radio) or go as far as to actually damage the radio. Turning the other radios off won't prevent this as shutting the power off doesn't disconnect the antenna from the expensive parts inside your receivers.

And as Mark mentioned:
Keep the glass mounts away from defrost wires.
Also, many cars have metallic film tinting. This will impact performance.

Pay close attention to installation instructions. The glass needs to be clean on both sides.

Done right they can work acceptably if your expectations are not too high. Trouble is that to get an efficient antenna on 2 meters or CB is going to require a long whip. Shortened whips will be poor performers.
 

Rred

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Check with your specific antenna maker for your specific car. Those antennas are all "coupled" through the glass, and the thickness of the glass, along with the materials used in any tint or film, and any metal (defroster or trim) running there can all affect operation.

You may have seen what might not be the same antennas on what looks like another 2011, but sometimes people just settle for poor performance, or one brand differs from another. "Through the glass" antennas can be a great idea but the devil is in the details.
 

PrivatelyJeff

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Thanks. I have specifically seen in a YouTube video of the ham antenna I want to use used on my exact model car, so I'm pretty confident they should work. I'm going to mount them at the top of the glass, far away from the defroster and the windows have after market tint, so they shouldn't be a problem.

If this was a truck or other larger vehicle I might go with larger/better antenna set, but this car is tiny and anything larger would make it look like an RC car. Lol

Also, I don't plan on using them much (except the scanner) day to day, mainly just on road trips, so I don't need much power. I'm mainly looking to just monitor traffic conditions and times when I don't have cell service.
 

PrivatelyJeff

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The equipment I'm going to try and use are:

Radios
Whistler WS1098 (or TRX-2)
Whistler WS1080 (or other cheap scanner on occasion)
Cobra 75WXST
Ham radio with remote head

Antennas
TRAM 1199 Glass Mount All-Band Scanner Antenna x2
Midland 18-258 40-Channel Glass-Mount CB Antenna
TRAM Dual Band 2M/440 Amateur Glass Mount Antenna
 

Chronic

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I have used the car stereo antenna on scanners with good results by using a simple splitter the scanners work well and the stereo doesent know the scanners are there. Pluss the "Stealth of less antennas on the vehicle.
 

PrivatelyJeff

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Why you dont try a Mag mount antenna, and glass mount dont work to well with CB radio at least it didnt for me......

I'm thinking of going that route now for the CB. I don't plan on using it much so, so digging it out for trips shouldn't be a problem.
 

PrivatelyJeff

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I have used the car stereo antenna on scanners with good results by using a simple splitter the scanners work well and the stereo doesent know the scanners are there. Pluss the "Stealth of less antennas on the vehicle.

Idk if that will work for me. My car has a dinky antenna on the back of the roof.
 

emtprt

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Just an FYI
Remove the whips prior to going to the car wash or you will have to go back when they clean thier drain trap. The adhesive and magnetic are not strong enough to hold when going through the brushes and curtains.

Mark

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PrivatelyJeff

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Just an FYI
Remove the whips prior to going to the car wash or you will have to go back when they clean thier drain trap. The adhesive and magnetic are not strong enough to hold when going through the brushes and curtains.

Mark

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Thanks, I've heard that, but I hand wash my car because I hate water spots on my windows and the can never get all the bug guts and bird droppings off of it. Lol
 
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