CB Antenna Help

[crazycanuck]

I am setting up a CB radio for my motorcycle. I haven't used a CB radio since I was a teenager and at the time I had built a few antennas. Unfortunately, I can't remember much of the theory.

I bought a Midland 75-822 Handheld. Today at Canadian Tire I bought one of those through the glass CB antennas. The arial is just under 22" tall. There is a metal base at the bottom of the antenna that is to be glued to the glass, and another metal plate that glues to the inside of the glass. Instead I was planning to mount the antenna on the rear plastic undertail fender. Would the signal travel through ABS plastic just as well as through glass?

Also, how do I tune the antenna? This antenna comes "pre-tuned", but has a lead that is about 8 feet long. I only need a couple feet of lead. How do I calculate the correct length of lead?

 

[RevGary]

From personal experience I can tell you that before you unpack that 'glass mount', you may wish to return it. The coupling through ABS is much less than through auto glass and much of the signal transfer will be eaten up in the density of the plastic.

FIRESTIK has a 'no ground plane' antenna and mount for your bike that is specifically designed for non metalic panels and cycle use. Tech details are found here among other places:

http://www.walcottcb.com/firestik-fg-noground-plane-foot-cb-antenna-kit-p-895.html

You will be happier with this style than trying to make a glass mount work where the loses in the coupler will leave you with poor comm. The Firestik is available in many colors to compliment your bike's color scheme.

The Firestik comes with 17 feet of cable. Don't wiorry about total coax length - just cut it once you have the coax routed to the radio and put on a GOOD quality PL-259 and coax diameter adaptor. Route your coax AWAY from the cycle's ignition module and high voltage components to lessen inductive noise generation.

 

[crazycanuck]

Thanks, I will look into ordering the Firestik antenna that you suggested. I didn't realize that there was a difference between a grounded, and non-grounded antenna.

Also, would it be a bad idea to mount the antenna such that it is pointing down from the rear fender just under the license plate? I realize that the best position is high on the vehicle away from other metal objects, but I want to have the minimum impact on the lines of the motorcycle.

 

[RevGary]

If I remember correctly, there is a good adjustable bracket with the antenna and several colleagues have mounted them on the chrome saddle bag mounting area about 10 inches off the ground. The profile of the antenna is lower than the rider's helmet in that postition.

 

[bsmotril]

Go to your local Harley Dealer and pick up one of their antenna kits for the touring bikes. These bikes come with CD, (optional on some radios), and have an add on antenna kit with the cable, bracket, whip, and various bolts. There is one mount made to the lids of a plastic touring trunk, and another to mount to a vertical surface like a shock mount or fender brace.

 

[LouisvilleScanMan]

If I were you I'd get another CB as well.I had one of those Midland 75-822 radios and all the reports I got over the air about it said it sounded vary bad and I found that you can't use it with batteries because the radio has too many features and doesn't hold enough batterys to run it all.Every time I would key mine up the batt low indicater would come on even with brand new batterys.Get a Uniden Pro-510XL or if it has to be a portable get a Cobra HH38WXST.

 

[TooLate]

Bluegrass:
Have you used the Cobra HH38WXST? Would like to use something more powerful than the short ranged FRS/GMRS stuff that's out there.

 

[LouisvilleScanMan]

Yes I own one and it's the top handheld CB on the market.Like any radio the better the antenna,the better the range.My only complaint is that the mic gain should be better,I've had people tell me that the audio is a little low even at short range but that's just handhelds for ya.Connect a good antenna and mic to it and you should be fine.The HH38WXST has a 4 watt output which is the max allowed by law but like most CB's it can be "tuned" up.

I assume you are going to use some sort of helmet mic/earphone set?