CB antenna - single or dual stick?

[ree]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Dick Renaud:
I have to work, my wife is spending up to my potential and beyond! </div></BLOCKQUOTE>
Tell her she needs to appreciate it more when you get paid in gratitude Thanks.

[rodster]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">1) Has anyone run the coax through the REAR marker? </div></BLOCKQUOTE>

Blasphemy!

Interesting idea. How would you get to the front?

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">2) Rod , how did you ground the rack? </div></BLOCKQUOTE>

I think it happened when the lights went on the Gobi. I didn't do anything else to ground the rack and I don't think the normal rack install would do it. I checked for continuity between the rack and a known good ground spot and it was 0.00 on the ohmeter.

[ree]

BTW rodster,
Here's a very useful prior link that documents the firestik+jeep mount, and even has a parts list on the last page.

http://elcova.com/groupee/forums/a/t...3686044512/p/1

[ree]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Dick Renaud:
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Al this may be a bit of over kill for raw CB, but I have had CBs in many diffent vehicles and building and have found that with a few simple steps you can get a lot more from your equipment. </div></BLOCKQUOTE>

Damn, why does every thing have to be more complicated that I thought it was going in

Dick, thanks for all this good info. Got a follow up question on the CB ground, though. With a mini handheld, where the whole thing fits in the palm of your hand, grounding the radio chassis doesn't seem to make a lot of sense. It's not real practical to attach a ground strap to the back of it. So this just limits the potential of these small radios right?

[Dick Renaud]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Dick Renaud:
Hard to get much better than that. Good work! </div></BLOCKQUOTE>

Check it again when you get the roof loaded with your gear.

[saturn75]

Go with the wilson 5000 one of the best out there.

[Rotary Flyer]

If you want some really good info on mobile radios...check out this web site http://forum.worldwidedx.com/ There are some real gurus of mobile radio there!

[rodster]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by ree:
I was also guessing that it isn't making good contact when folded down. Hence the idea to directly wire the top portion to the stud.
</div></BLOCKQUOTE>

That extra wire is for ground, yes? My concern about adequate contact isn't about ground but rather, the signal itself.

This one is way over my head so hopefully Dick will have something.

[ree]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by rodster:
Still have done no tuning. </div></BLOCKQUOTE>
Good job. I'm jealous. I just know mines going to be all messed up when I get around to it.

more picts????

[rodster]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by CslRkH2:

By placing it in the middle does that make it hard to get to? </div></BLOCKQUOTE>

Nope, and that's one of the reasons I put it where I did -- ease of access. I open the sunroof, reach up, slide up the spring-loaded sleeve that contains the pivot joint and lean the whole thing down.

I considered putting it on the driver's side for easy access but then I wouldn't have the full benefit of the what roof I have now. Plus, it just looks better in the middle.

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">If your OK with a middle of the roof location, why not mount in the exact middle through the mesh GOBI deck? </div></BLOCKQUOTE>

No can do. I carry recovery gear and other stuff up there regularly. I need the rack space.

Appreciate the other input, too, CslRkH2!

[rodster]

Thanks for the link, Ree. I've been all over that thread a few times.

Took a drive down to Boulder City today to Radio World. What a place! It's a small shop run by a guy who was very patient and answered all my questions.

Snipping one connector is standard stuff. He didn't have the coax like the one pictured above but he did give me the replacement connector. That'll be easy to install since I already have the coax crimper.

I bought a standard issue mount that'll clamp on my Gobi rack. Also and based on Phil's recommendation, I bought a swivel joint (not a spring) to put between the antenna and the base. That'll allow for laying the antenna flat for garage parking and when driving through tall brush.

I ended up with a four foot antenna. The difference in money between it and the shorter models was peanuts but the increase in range is, in the shop owner's opinion, worth it. After hearing his explanation why I have to agree. I don't know if the added length and range will every be necessary but it'll be nice to have if it is.

I also picked up a SWR meter to tune the antenna. It was cheaper to buy the meter ($20) than drive back down to his store for the free tune, which he did offer.

Here's a different take on coax length: The gent at the radio shop (he's been a ham for decades and playing with CBs since Smokey was a bandit) said that length is not critical. He said the coax needs only be as long as it takes to reach the radio. He did advise I have the install nearly finalized before tuning so I expect the coax length will impact that.

Thanks again everyone for all the assistance. I'm off to the garage to install.

[rodster]

Great stuff, Dick. Thanks much. And thanks, RF, for the link.

[Dick Renaud]

As a HAM since the fifties and a commercial 2-way shop owner for 15 years dealing in low band VHF (39mhz) and CB as well as high band and UHF, here is some info.
If you have a properly grounded vehicle, cable length is not a factor, in fact at low power CB shorter lenghth is an advantage. You are attempting to keep the resistance of the cable balanced with the radio and antenna to get maximume power transfer.
Grounding: Must include grounding the antenna to the roof, if you are using complex mounts with open ground brain from the coax, an additional short length of copper braid, flattened and attached between the antenna ground screwed with star washer into the roof and sealed with silicone or other water tight seal will help. Body ground, you also should ground the body metal under the vehicle to the frame using the copper braid and weather sealed.
Last but not least, ground the negative post of the battery to the frame in the same manner. The regulare vehicle electrical ground is not all that solid and needs this extra solid ground. In all cases wire brush the surface area and clean with alcohol. On more help is to ground the tail pipe to the frame. It can cause electric noise.
Power, it is alway best to run a "home run" positive and negative cable * or 10 gauge from the batter to the radio. If you hook up to any other vehicle electric you will get noise. Vehicle electrical systems have very poor RF suppression. Check with your local sound installer. They always connect direct for noise suppression and heavy power need.
Tuning, the previous post is correct, the antenna must be in use condition when tuned. One thing many people forget when tuneing especially when the mount is over the drivers door, close the door.
One last thought, the Firestick is a great antenna because you can tune it easily and retune it any time you add something to the roof a9lights, bars etc). The rule for antennas is the longer the better. The 4' Firestick is the best comprimise for a low profile, foldable antenna.

In radio, every little thing adds up to major difference in results. You can short cut it if you don't care about the extra distance or clarity.

As a cop and emergency worker for many years I always go the extra step for the added security in that one situation when you REALLY need the extra.

[rodster]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by KenP:
Timgco had two on his H2. They were Firestik's I believe. </div></BLOCKQUOTE>

I've seen pictures of his dual setup and as I recall, there was a story about him at the Radio Shack in Moab, which lead me to believe his antennae are the ones linked-to and pictured above (the "pre-tuned" goods).

But I agree, it does sound like bull. Seems to me the radio and quality of ground would affect the tune. Not to mention that maybe over time the tune shifts and calibration is necessary.

Thanks for the link to Firestik. I'm on their site now.

[dochummer]

I agree with Alec, two looks cool. I'm just too lazy to put another one on...

[Dick Renaud]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by rodster:
[quote]Originally posted by Dick Renaud:

You are attempting to keep the resistance of the cable balanced with the radio and antenna to get maximume power transfer. </div></BLOCKQUOTE>

I hear two possible things here (and I may be way off so bear with me, please):

1. More length = more impedance which = less transmit power?

You are close, but impedance should remain constant at 50 ohms. Length = resistance which = heat which = power loss. the more lenth the more loss and at about 4 watts or less output power at best (the 5 watts is input power) you need all you can retain. Also, there is some increase in recieve (mostly in noise reduction) with shorter coax.

I had a choice between Firestik and Wilson. The shop owner was very high (to say the least) on Wilson so based on his recommendation and my desire for a flex unit, I bought the Wilson Silver Load Flex 4 . Any thoughts on that?

Wilson is a good antenna, but generally longer and more difficult to tune. If the additional length is not a problem its fine. I should mention that a flexable antenna changes radiation pattern as it sways back and forth or lays back at high speed. The Firestick is ridgid and holds it pattern better. I would use a spring with a firestick to take minor hits better, but as mentioned earlier, a ridgid antenna on the trail may be damaged. The only antenna that will take the trail is a short rubber antenna and you loose distance with that. A comprimise that we used to use on police vehicles is a Larsen with an NMO mount mounted into the roof with a backer plate. The Larsen is very flexable and with a solid mount will take a lot of abuse as long as it is not hit to close to the base.

You mentioned the antenna can be retuned when something new is added to the roof ...

When I'm headed off-road, I mount quite a bit of metal recovery gear on the roof rack. Will that effect the tune? If yes, given that I'll most often use the radio when off-road, would you advise I tune with the gear on?

Absolutely tune with everything on that you will normally run with. Anything in proximity to the antenna can de-tune it. One addition though, the rack etc should be grounded to the roof with braid. The regular mounts are not a very good ground. Also, any loose body metal ( hood, lift gate etc) should be Bonded (grounded) with braid. Again, refer to Alans web site referenced in my earlier post.

[Dick Renaud]

You shoud finish by sealing all the connections with clear Plasti Dip including the clamps on the rack. That will keep the contacts dry and tight. The hinge join don't use the Plasti Dip, use dialectric grease and re grease it periodicaly.

[rodster]

Base ...

[ree]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by rodster:
This model cable from Firestik is made for easy routing. If I can find it, this looks like the ticket, yes?


</div></BLOCKQUOTE>

Yes. This is what other's have said works (the MU-8R18), and I bought the same on that recommendation. Never having seen the marker light holes first hand, I can't say it will work, but it looks like it will.

I'm sure Phil will know; he seems to know something about everything


I'll semi-hijack the thread and ask others where do you put all the excess coax? I defintely don't need all 18' and Firestik says not to coil it (RF choke). I suppose this means it's got to be spread around the headliner????

[Dick Renaud]

There is a difference between Electrical Ground and RF Ground. The VOM reads Electrical Ground. You need more expensive test gear to read RF. The best and cheapest this is to be sure that you have good,Clean (wire brushed or dremmeled), tight physical ground connection between the antenna and the ground surface. Something I forgot in my other post is that you need a good physical ground between the Radio chassis and the vehicle chassis. The can be acheived if you have a large screw on the back of the radio or drill a hole in a clear area of the back plate and, in either case attach a flat copper braid or flat copper strap with stainless steal nut and bolt or replace the chassis screw with stainless screw and stainless star washers. Seal the connections with RTV silicone or Plasti Dip. This seals out moisture and prevents the hardware from working loose. If you don't seal them, check them for tightness monthly. A ground that is not very tight can cause static interference. It may look tight, but tighten it to be sure. The copper strap is the best grounding material because RF travels on the surface of the copper not inside and strap has more surface area. I mentioned tailpipes before. The are a leading cause for noise in ham HF (CB frequencies fall in that range) frequencies. When grounding tailpipes it is best to use a stainless steel pipe strape to secure the ground and use a high temp sealing material.
One other point is to solder all connections, no clippies.
If you want lots more info on mounting and wiring and grounding check this site:
http://www.k0bg.com/ Alan is what is called in HAM an ELMER. That is a very experienced HAM who helps newer HAMs figure it all out. HAMs by nature are experimenters and are always tweeking and seaking better ways to get the most out of the least. I have spent a great deal of time asking ELMERs for advise and Alan is one of the most knowlegeble and acurate ELMERs I have found.

Al this may be a bit of over kill for raw CB, but I have had CBs in many diffent vehicles and building and have found that with a few simple steps you can get a lot more from your equipment.