At 03:28 PM 11/18/04, you wrote: >The midland xtal rig 13-500 is a very low draw rig as suggested here.
I forgot to mention one trick - add a toggle switch to the back panel and use it to shut off the dial lights during the day. >I have used an ICOM-02 with a 10W brick on my motorcycle quite >effectively. As Mike points out, the key to performance is the >antenna. Yep. A 1/4 wave antenna needs a ground plane, and a bike or motorcycle doesn't have one (almost as bad as an HT). >There are several hams here in Austin TX that operate bike >mobile. KB7UQD and WB5AOH might share their thoughts with you. BOth >have email and are on QRZ.COM. My first motorcycle antenna was on >the luggage shelf behind the passenger seat. I first used a >Newtronics/hustler 5/8 antenna. The 12in sq luggage rack was not >enough ground plane with the antenna at the back edge. The local cops use UHF and their motorcycles have a 6" spike in the middle of the fiberglass "trunk" behind the seat. The radio tech puts copper foil (available at model aircraft shops) under the trunk lids and it's barely enough - and that's on UHF which has one third the wavelength of 2m. Some of the newer cars have fiberglass trunk lids and roofs and that solution works there also. >I added a loop of 1/2 in CATV coax to form a ground radial or plane >behind the bike and that greatly improved performance. I would place >the antenna behind you with a small metal base and some horizontal >wire loops to the side and rear to act as ground planes. I think >nearly any wire will work. I'd make it just barely rigid enough so >that the bike falling by itself won't bend it but if you fall it will >bend. My loops stick out about 15 inches. I have three loops each >covering about 45 degrees. The wire goes out straight about 6-8 >inches and then curves around reaching 15 in from the base plate at >the 22 degree point. The wire then curves back in. Again there are >three loops. > >I get a fairly uniform pattern where as before the antenna only >worked to the front. The SWR is reasonable about 1.4:1 compared >with 1.2:1 on a car (after playing with the length). I now use a >comet dual band antenna with a dual band rig. Hope this helps. >73 Ed K3SWJ This is why I suggested a 1/2 wave antenna - it doesn't need a ground plane (although if you have one it helps). Look at the Larsen NMO-WB150C antenna at <http://radiall.jouve-catalogue.com/part_search.asp?Lang=EN&SRCH=WB150C> or change the trailing C to a CK if you want the complete kit including antenna mount and cable. I'd try the 1/2 wave antenna, and if it's not enough you can try the flower-petal loops mentioned above - I'd experiment with it using some #12 or #14 electricians copper wire (it's cheap enough). If it works for you then you can look for something more sturdy. Or use a 10w brick amplifier. Mike WA6ILQ Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
