J&M offers two grades of headsets. For those thrifty individuals there is an entry level helmet headset (8154 series) that is competitively priced and includes the entire cord section with nothing else to buy.
The (279 Series) is for those looking for a balance of economy and quality.
The (629 elite series) is for those discriminating individuals who only desire the best. This helmet headset is top of the line.

JMCB-2003 — the world’s first, all-in-one, handlebar-mounted, motorcycle communication system! Includes CB, WX reception, and motorcycle intercom capabilities. J&M Products – Click Here

The Compressor, a truly remarkable device. After several years of research and development, in an effort to gain as much clarity and distance as possible with your Harley-Davidson’s factory communication system, came the birth of the compressor.

This device will increase your factory CB radios loudness and distance by 200%, guaranteed.
There is nothing else that will come close to producing the performance characteristics of the Compressor.
The Compressor, cutting edge technology for demanding motorcycle enthusiasts
 
This is a two part performance enhancement consisting of installing the Compressor, then modifying and tuning the antenna system and finally adjusting the compression level of the Compressor device.
Check out this video for more info, images, and a Video that explains what is happening under the hood, so to speak.
The Compressor – More Info –  Click Here

Portable radios can be added as a functional communication system for bikers if it is done right.

There are basically three types of systems.

CB Radio, GMRS, and FRS. The most compatible type of system is CB Radio. This system has been offered by several bike manufactures for some 40 years. If you want to communication with others at rallies or other events you will find that most bikers will be using CB Radio.

FRS and GMRS are high frequency FM transceivers. I prefer GMRS for several reasons. The first is GMRS provides the best performance. 20 to 30 miles of range is possible with high end radios. The second reason is high quality water proof radios are available.

The CB system is set up slightly different from FRS and GMRS. The CB system will require a permanent antenna system, a PTT (Press to Talk) switch mounted in a convenient and safe place such as the left hand grip, and a tank bag.

We recommend a tank bag for several reasons. The radio will be isolated from the elements, and all cables will be routed to one central location other than the biker. If the radio is mounter to the bikers belt for example, the PTT switch cable, the antenna coax cable, the helmet headset cable and the pos/neg power supply cable will all be connected to the radio that is the bikers side.

This is a spider web at best and can’t be safe in the event the biker must dismount quickly.

If the radio is in a tank or windshield bag all cables are routed to the bag. Only one cable (the helmet headset cable) is attached to the biker. Most headsets have a quick detach connection inline making a quick dismount possible.

FRS and GMRS systems are set up the same with the exception of the antenna system. No external antenna system is required and exceptional results are possible with the rubber duck antenna on the radio. CB radio will have poor results from a rubber duck style short antenna.

Expect 25 to 75 yards of distance from this type of antenna on a portable CB and 20+ miles using GMRS with the short rubber duck style antenna.

Create Higher Performance

Overview

The Antenna must be tuned for all applications. Factory systems, aftermarket ad on’s, replacement antennas, it makes no difference. The antenna SWR MUST be set! There is no pre-tuned antenna.

SWR stands for standing wave ratio. Basically it is a very simple concept. When you transmit a certain amount of the wattage is reflected back into the transceiver. Dammage to the radio will occure If the amount of wattage that is being reflected back into the transceiver is to high.

So the SWR is a measurement of how much signal is going out the antenna, versus how much signal is reflected back into the transceiver. An SWR level of a 3.0 will damage the transmitter. A 2.0 SWR is about an 11% loss and the transmitter of the radio will run hotter as compared to a lower SWR. Amplifiers do not like high SWR’s.
A radio with a built-in amplifier should not normally be used if the SWR is above a 2.0. While they might get away with it the duty cycle on transmit is reduced. The transmitter will warm up much quicker with a higher SWR as compared to a lower SWR.

Let’s talk about setting the SWR’s

All CB antennas are tunable. Antennas that have an easy, often mechanical, tuning device are referred to as a “tunable antenna”. Accordingly, many people think the other antennas are not tunable and so they make no attempt to have the antenna tuned. This is a critical mistake.

Wire-wound antennas (without mechanical tuners), that test electrically long (higher SWR on ch 40), can be tuned by removing wire from the top. Remove the antenna cap, remove one wrap of wire and cut it off. Put the cap back on and recheck the SWR again on ch 40 & ch 1. As long as the SWR is higher on channel 40 continue to cut. Do not cut more than one wrap at a time. If SWR testing indicates the antenna is electrically short (higher SWR on ch 1), test for a ground problem. Touch the antenna bracket while keyed and watch for SWR fluctuation. Do not touch or even get close to the antenna. Move the coax around bending it, again watching for SWR fluctuation. If the SWR fluctuates a ground problem exists and must be corrected before proceeding.
If there was no fluctuation bend the end of the wire straight up the fiberglass shaft and lap it over the very top of the fiberglass shaft. Check the SWR on ch 40 & ch 1. The goal is to reverse the situation so that ch 40 has a higher SWR than ch 1. If ch 40 is higher cut 1/8 inch of wire, put the cap back on and check the SWR on ch 40 & ch 1. Continue with this process until ch 40 & ch 1 are relatively the same.

Wire-wound antennas (with mechanical tuners), that test electrically long (higher SWR on ch 40), can be tuned by adjusting the mechanical device at the top of the antenna. Remove the antenna cap, and adjust the rod down or if threaded turn the device clockwise. Put the cap back on and recheck the SWR again on ch 40 & ch 1. As long as the SWR is higher on channel 40 continue to adjust the rod down or if threaded turn the device clockwise. If SWR testing indicates the antenna is electrically short (higher SWR on ch 1), test for a ground problem. Touch the antenna bracket while keyed and watch for SWR fluctuation. Do not touch or even get close to the antenna. Move the coax around bending it, again watching for SWR fluctuation. If the SWR fluctuates a ground problem exists and must be corrected before proceeding.
If there was no fluctuation adjust the rod up or if threaded turn the device counter-clockwise. Check the SWR on ch 40 & ch 1. Continue with this process until ch 40 & ch 1 are relatively the same.

Solid fiberglass antennas (straight or helical wire impregnated in fiberglass resins) that are electrically too long (higher SWR on ch 40) can be cut shorter with a hacksaw or grinder. Cut only 1/4 of on inch at the most at one time. If the SWR test on one of these antennas indicates that it is electrically short (higher SWR on ch 1), the addition of a spring or quick disconnect (or both) is the only way to correct for the short condition.

Base loaded antennas with wire whips have a set screw (or two) just below the area that the whip is inserted into the loading coil. By loosening up the set screw(s) you are able to slide the whip up or down as required. If the SWR is higher on ch 40 slide the whip down, If the SWR is higher on ch 1 raise the whip.

Setting the antenna SWR with an amplifier can get involved. The antenna SWR is calibrated at the back of the amplifier with the amplifier in line and turned off. Once the antenna is properly tuned the meter is removed and re-installed at the radio with the amplifier in line. The antenna SWR level is then measured with the amp off and then with the amplifier switched on. The SWR level must be at an acceptable level at the radio under all conditions. The conditions are with the amp off on channel 40 and 1 and with the amp turned on, on all power levels of the amplifier on channel 1 and 40. Most shops don’t check the SWR match at the radio with the amplifier turned on. This is a critical mistake. With these steps added the SWR calibration can turn into a multi hour event at times.

 

How much range should I expect out of my system?

There are MANY factors to this equation from the length of your antenna (longer is better), length of coax (18 feet is optimal), brand of antenna- they are not all equal
(check out the Firestik FL series antennas)- antenna SWR tuned?, has proper antenna ground been achieved?, has the radio been performance tuned? how about all of the above for the biker you are communicating with and how much (white noise) are you experiencing today. (White noise) changes daily.

Below is approximations only.

1) Short antenna (6 inch rubber duck) non tuned radio. Approximately 50-100 yards.
2) Short antenna (1-2 foot) non tuned radio. Approximately 1/4 to 1/2 mile.
3) Long antenna (3-4 foot) and non tuned radio. Approximately 3/4 to 1 1/2 miles.
4) Performance tune the J&M radio – increase by 40-50%
5) Add our compressor to a GL1800 or a Harley – 5 miles typical.

About Performance Tuning

The Performance tune up increases the output of the radio by approximately 50%. The receiver gain is typically 20-30% over stock specs.
This modification includes the following changes in order to enhance the radio’s performance.
– Adjusting the modulation for maximum output without distortion.
– Aligning the receiver for optimum signal to noise ratio.
– Adjusting the squelch range
– Frequency adjustment to zero tolerance.
– Perform a complete check of all functions.
– Perform a visual of the circuit board for cold joints and flaws.

A properly tuned radio should be loud but also clear.

 

 

 

 

Our first recommendation of course is to have your system checked out. Once your system has been given the thumbs up consider other factors such as the length and type of your antenna, performance characteristics of your radio – tuned or stock? and finally terrain and atmospheric conditions.

Read on for a scientific explanation of what is really going on under the hood so to speak.

Scientists track solar cycles by counting sunspots — cool planet-sized areas on the Sun where intense magnetic loops poke through the star’s visible surface.

Hathaway is an expert forecaster of sunspot numbers. “Sunspot counts peaked in 2000 some months earlier than we expected,” he recalls. During solar maximum, magnetic fields above the Sun’s surface become impressively tangled, particularly near sunspots.

Twisted magnetic fields — stretched like taut rubber bands — can snap back and explode, powering solar flares and coronal mass ejections. The subsequent dip toward solar minimum seemed premature to Hathaway, and indeed it was. Before long, sunspot counts reversed course and began to climb toward a second maximum that now appears to be only a few percent smaller than the first.

Solar Max eleven years ago was much the same. A first peak arrived in mid-1989 followed by a smaller maximum in early 1991. Sunspots are the most visible sign of those complex magnetic fields — but not the only one. Another sign is solar radio emissions, which come from hot gas trapped in magnetic loops.

“The radio Sun is even brighter now than it was in 2000,” says Hathaway. By the radio standard, this second peak is larger than the first. In fact, if the ongoing cycle proves to be a double, it will be the third such double-peaked cycle in a row. The last two sunspot cycles also had double-featured maxima

The source of Radio NoiseThe Radio Sun


Twisted magnetic fields
Twisted magnetic fields


Where is the best mounting location for the antenna system?

All the way to the back of the bike. To start with it simply looks correct but that is not all that is going on. Lets take an auto for this example. If we mount the antenna dead center in the middle of the roof, the system will perform equally front and back. Lets say for easy math that this equals 10 miles. 5 miles to the front and 5 miles to the back. Now lets move the antenna to the rear bumper. What impact does this have?

The performance now makes an interesting shift. The total distance is still 10 miles but it is now 8 miles to the front and 2 miles to the back. This is due to a ground plane effect. The same is for the motorcycle. Distance in a given direction can be increased by proper placement of the antenna system.

The license plate type mount offered by J&M is an excellent choice for most bikes. However, we highly recommend making a change to the mount. The ground strap that is included should be removed from the stud. Drill a hole in the bracket, remove the powder coating and re-attach the ground strap. Remove the powder coating on the underneath side of the bracket at the point the coax connector contacts the bracket.

Remember paint and primer are your enemy.

Adding a second ground strap & attaching it to a different ground potential should be considered.

illustration:

motorcycle antenna mount