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[DESERTBEAR54]

Here is a good antenna replacement for the long whip antenna's that come from the OEM. No loss on CB and work excellent with FM.

http://www.easternperformance.com/index.php?main_page=product_info&products_id=1603

[BaggerDave]

$80.00 for the pair seems ridiculous to me!

[Texas 103]

My Experience with that antenna is there is a loss with it. I reinstalled the stock antenna and had to move up the Squelch up 4 bars from  one bar and I now was able to hear conversations that I couldn't hear before    The ears aren't nearly as good with the short antenna. I believe CB is "line of sight" and when the antenna is shorter is affects it's performance. That was my experience last week...Greg

[miker]

$80.00 for the pair seems ridiculous to me!

Gaaaa!

[BigR55]

If the $80.00 units work it would be worth it. I bought the $30.00 ones and changed back to the whips like Texas wrote about above. Is there a place to use a SWR to check the CB?

[DESERTBEAR54]

The SWR's on these shorty's are the same as the whips on the CB.

[RedDevil]

The SWR's on these shorty's are the same as the whips on the CB.

Not true,  the factory whips are at or over 3:1 at mid-band, (channel 20).  The J&M's are at around 1.8:1.  There is so much reflected power going back into the radio with the stock whips, I'm surprised the CBs even work.  U.S. CBs operate at 27MHz which propagates at both ground wave and sky wave...so it's both somewhat line-of-sight but more effective for long-haul communications.   There is a thread that discusses all of this, just do a search for CB SWR measurments.  The J&M's are very good antenna.  Keep in mind that CB comms are not going to be optimum on a motorcycle anyway...the bike doesn't present much of a ground plane for the antenna, and they don't use marine-type antennas on the bike, so transmissions are not going to be optimum, even with the best-cast non-marine type antennas.  (Marine-type antennas don't rely on the body of the vehicle for a ground plane.)

   

[sawyerghost]

I've been using the J & M Shorties for a couple of months.
They work great, and if you need a dealer that is near me but will ship anywhere in the country, Go to his Website,
twowheelaudio.com. Located in Murray, Kentucky
He travels at all shows, and is a strong dealer for all J & M Products.
10% Off, No Sales Tax, and order over $200.00 Free Shipping.

[Coyote.]

Not true,  the factory whips are at or over 3:1 at mid-band, (channel 20).  The J&M's are at around 1.8:1.  There is so much reflected power going back into the radio with the stock whips, I'm surprised the CBs even work.  U.S. CBs operate at 27MHz which propagates at both ground wave and sky wave...so it's both somewhat line-of-sight but more effective for long-haul communications.   There is a thread that discusses all of this, just do a search for CB SWR measurments.  The J&M's are very good antenna.  Keep in mind that CB comms are not going to be optimum on a motorcycle anyway...the bike doesn't present much of a ground plane for the antenna, and they don't use marine-type antennas on the bike, so transmissions are not going to be optimum, even with the best-cast non-marine type antennas.  (Marine-type antennas don't rely on the body of the vehicle for a ground plane.)

   

Well yes and no. The factory antennas will match and perform the best IF they are tuned. The dealers don't tune them so the match out of the box is marginal. If you take the time to tune the long whips, you can get them near 1:1 and there is no short antenna that will out perform them. Having said that, I have the JMs on my bike for the reduced length and looks. I took the time to check the tuning on the JMs and had to return them twice to get an antenna that would match well for the CB. While I know my CB performance is less, it's still good enough for what I need.

As for the statement that marine antennas don't rely on a ground plane, well that would depend on the antenna. Antennas for marine use are not much different than for land mobile use. And there are antennas designed to require a ground plane, and those are not. At 27MHz (CB band) the antenna is so much shorter than the wave length that ground plane is always a factor. The best you can do is tune to what you have. When I used to design low band held held radios, we actually tuned the antennas to use the average human holding the radio as a counterpoise for the antenna.

[bunt]

Well yes and no. The factory antennas will match and perform the best IF they are tuned. The dealers don't tune them so the match out of the box is marginal. If you take the time to tune the long whips, you can get them near 1:1 and there is no short antenna that will out perform them. Having said that, I have the JMs on my bike for the reduced length and looks. I took the time to check the tuning on the JMs and had to return them twice to get an antenna that would match well for the CB. While I know my CB performance is less, it's still good enough for what I need.

As for the statement that marine antennas don't rely on a ground plane, well that would depend on the antenna. Antennas for marine use are not much different than for land mobile use. And there are antennas designed to require a ground plane, and those are not. At 27MHz (CB band) the antenna is so much shorter than the wave length that ground plane is always a factor. The best you can do is tune to what you have. When I used to design low band held held radios, we actually tuned the antennas to use the average human holding the radio as a counterpoise for the antenna.

I know nothing about CB's is there a way to tune your radio for optimum performance or are you matching the individual antenna to your radio?

[Coyote.]

I know nothing about CB's is there a way to tune your radio for optimum performance or are you matching the individual antenna to your radio?

For the CB on a bike, you really need to match the antenna to the specific bike. Even small things tend to make a difference. The reason is when you match to a counterpoise, like the bike, it tends to be a high Q match. What that means is the match bandwidth is fairly narrow (maybe 3 or 4 MHz at 27 Mhz). So if you change something, even by a small amount, it can move the match window away (say 10% up or down) from the radio's operating range. The result is the match degrades (ie higher SWR). It's best to tune the antenna on the bike, with the equipment you have most often. Not that we can do much about it but you would be surprised how much the passenger will shift the antenna tuning. If you ever set up to test your CB with an SWR meter, just take a reading with and without someone near the antenna. 

[DESERTBEAR54]

Just add a 200 watt linear!!! Ride Hard and Fry Hard!!!!

[sawyerghost]

Supposedly,
The J& M Shorties are tuned for your Specific Bike, Harley, BMW, etc.
These seem to work well for our application.
 

[WFP]

Do you mean:

http://www.twowheelsound.com/

??

I've been using the J & M Shorties for a couple of months.
They work great, and if you need a dealer that is near me but will ship anywhere in the country, Go to his Website,
twowheelaudio.com. Located in Murray, Kentucky
He travels at all shows, and is a strong dealer for all J & M Products.
10% Off, No Sales Tax, and order over $200.00 Free Shipping.

[sawyerghost]

Yes WFP,

I stand corrected on the Website to purchase J & M Product in Murray, KY.
10 % Off, No Sales Tax, and Free Shipping with purchase over $200.00.

Correct Website is http://HTTP://www.twowheelsound.com