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FC-40 Mobile/
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kd4hri
Is anyone else using the fc40 mobile to drive a whip?
I have my FC40 mounted onto the spare tire bracket of my RAv4. It is connected to a 1/4 CB whip (only 2-3 inches of wire between.) The ground on the FC-40 is directly connected to the ground of the vehicle and all part of the vehicle and bounded together by grounding straps. Each lead into the radio, antenna control, mike, remote head,and speaker, has an RF choke on that wire. Works great on 30-6 meter, but will not tune 40m. If I add 6 feet of wire to the tip of the whip, it will tune 40m NP. Questions: 1. Anyone have this set up working on 40m? 2. Yaesu's whip for the FC-40 is 8.2 feet long, the CB whip is 9'. Should I trim the whip back to 8.2 feet? 3. Should I ground strap the spare tire itself? 4. Anyway to add 'length' without having a trail 6 feet of wire off the end? A capacitor across the FC-40 terminals? A small coil between the FC-40 and the whip? Also, 17m will tune, but compared to 30,20,15,12,10 and 6, it seems to have higher (1.7 to 1.9) than the other bands (less than 1.5 all) |
开云体育Years ago i had a fc1000 in my car (rf wise almost like the fc40) Problem in almost al setups is rf isolation on the lower bands …. A short whip becomes more and more impedance on the feedingpoint several hundrets to thousands of ohm A military whip with its foot was the solution … 3.5 megs with a 2.5m whip … no problem Topband with a 5m whip bent over the car in a bow form … If you find no match on a band (40 you said) why not bring a capacitive hat to the whip Better as a coil (lower loss) Dg9bfc Sigi ? ? Von:
YaesuTuner@... [mailto:YaesuTuner@...] Im Auftrag von kd4hri ? ? Is anyone else using the fc40 mobile to drive a whip? |
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kc5cqw
It looks like you have it covered except...
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What are you using for a mount? Isolation from ground here is critical. Take a look at my posted pictures; I use a Breedlove HF Insulator. Well worth the $40. You need a high voltage dielectric with very low capacitance. This setup can produce upwards of 10's of kilovolts! I added a cap hat just incase; it seems to help. Personally, I haven't made a contact on 40m yet. My estimation is that I only have about 25-40% efficiency on 40m. Probably less... I haven't dedicated any significant time in figuring the numbers. My setup tunes from 7.1MHz up to 6m just fine. Feel free to contact me for further info if needed: my call at gmail dot com --- In YaesuTuner@..., "kd4hri" <mark@...> wrote:
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