Radio question

[SHMIV]

A few minutes ago, I was sitting at a truck stop, and heard a guy on the CB offering a radio for sale. I asked him what he was selling, and he said he had a Stryker SR-655HP; $150.

I figured a $250 radio for $150 wasn't a bad deal, so I bought it.

Question is: How do you tune an antenna for a 10 meter radio? When I tune an antenna to my basic 40 channel Cobra 25, I tune on Channel 20.

I tried Googling an answer, but I guess I'm asking the wrong questions

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[MarcSpaz]

10 meter goes from 28000 KHz to 29700 KHz. You need to tune at 28850 KHz, which is the center of the band. This will allow the best performace through the entire band.

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[SpanishInquisition]

... and operation on the 10 meter band requires a ham license. Tech for a bit of it in SSB, general of better for other modes and a bigger slice of the spectrum.

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[jdonovan]

10m is a bit unique in that the phone (aka voice) sub-band is right in the middle.
28.300-29.300Mhz So tuning for mid-band is going to suit you well.

As others mentioned you need a ham license for this. The FCC has been active lately in tracking down truckers misusing 10m, and issuing large fines. Also there is a sub-segment of the ham hobby that seems to be dedicated to finding unlicenced interlopers as a 'sport'. So if you're not licenced, beware.

[MarcSpaz]

There is a team of guys around here that do that. They have some pretty advanced electronics and software to find illegal users... even mobile ones.

If you don't already have a license... it is very easy to get one. The HAM world is pretty good at being self-regulated. Mostly if you are polite and don't break the rules... the community is very welcoming.

[SHMIV]

Yeah, I was aware of the license requirement. The radio has CB capabilities, though, so I bought it, anyway. Usually, I stay on Channel 19, and don't have any immediate plans to change that. I figure that I now have an excuse to get a radio license, which is something that I have been wanting to do since I found out about it. In the meantime, I figure that it would be a good thing to have out in, say, Wyoming, in an emergency. Out there, I have no cell service, not many folks use a CB, but I see plenty of mobile ham rigs. While I'm not particularly inclined to operate a radio illegally, I have absolutely no problem doing so, if my life or health are dependent upon it. If they want tofine me for illegally transmitting, as opposed to freezing to death because my truck broke down in a snowstorm, so be it.

Next question, I guess, would be, the tuning recommended above; would that work well with the radio switched to CB mode? Or would Ihave to do ssomething different?

I appreciate the help and advice; y'all are saving me from spending a lot of time trying to figure out the right word combination to enter into the Google search bar, lol.

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[jdonovan]

While I'm not particularly inclined to operate a radio illegally, I have absolutely no problem doing so, if my life or health are dependent upon it. If they want tofine me for illegally transmitting, as opposed to freezing to death because my truck broke down in a snowstorm, so be it.

Strangely enough, this is where the law becomes reasonable. If you need to summon help in an emergency, any frequency, any mode is legal to use for any person.

Next question, I guess, would be, the tuning recommended above; would that work well with the radio switched to CB mode? Or would Ihave to do ssomething different?

You need a SWR meter that covers the frequencies you are tuning the antenna for.

something like this
http://www.diamondantenna.net/sx20c.html

[SHMIV]

I do have a SWR meter; it's a Radio Shack model. Aside from the SWR, which ranges from 1 to 3, and then goes to red, it also measures power output up to 2,000 watts. Also, it has a switch to toggle between "AVG" and "PEP".

In the past, my concern has always been with the SWR reading; outside of curiosity, I'm not generally concerned with the power output. If I can talk to the other trucks, I'm a happy guy.

Aside from the meter being a Radio Shack model, and probably not the highest quality, doyou think that it will be work? If not, I did see one made by Astatic that I had previously considered looking for an excuse to purchase. ..

Funny thing with radios; while GF is always excited about guns, it's hard to get her to sign off on radios and related paraphernalia. She doesn't understand why I want to spend moneyto talk to strangers, lol.

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[MarcSpaz]

I wouldn't trust a Radio Shaft SWR meter for any rig that puts out more than 1.5 watts. They are not good quality. Diamond makes the best meter in my opinion.

You want to keep your SWR under 1.5. The closer to 1 you are the better. The more over 1.5 you are, the more heat your final transistors in the amp circuit generate, and the faster they break. With an SWR over 2, I would expect the radio to fail in weeks/days. Over 3, I would be shocked if you got 10 minutes of talk time.

A lot of folks will buy automatic tuners to help protect the radio. Even if you try to transmit with no antenna or on an antenna with a dead short, the tuner will not allow the match to go above 1.5 SWR.

As far as general tuning goes, I would get a 102" steel whip with an adjustable mount, allowing you to adjust the antenna height an inch in each direction without cutting the whip, then tune for best performance on CB19. If you use the same setup with an auto tuner, it will work well for 10m too.

Keep in mind, you want to tune for CB19 because you are restricted to 4 watts on AM and 12 watts on SSB when using the Citizens Band. You want to have the best antenna performance, generating transmit power instead of heat in the finals, to make up for the lack of power. Once you get into 10 meter, you can make-up for the lack of precise antenna tuning by using a max of 200 watts for technician class license or 1500 watts for higher class licenses. But again... use that auto tuner to protect the rig.

[SHMIV]

I doubt that I'll be hitting 200 watts any time soon. The radio that I have only puts out 70; though, according to the seller, it's been "worked on", so it may put out a little more. Generally, the radios that come from truck stop CB shops are peaked and tuned, or have some sort of modification done to them, before they even hit the shelves. I guess that they figure that the purchaser will want that work done, anyway, so they just do it. And, this radio came from one of those CB shops.

For the time being, 70 watts suits my purposes. Once I can find figure out what I need to learn to get licensed, learn it, and take/pass the test, I will see about higher power outputs. But, not too much higher. I'd hate to fry the electronics in this truck. My buddy bought an amp for his radio, and every time he tries to use it, it sucks power from the rest of his truck.

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[SHMIV]

I was trying to search for automatic tuners; Google keeps showing me tuning devices for musical applications. Is there another name for such a device?

As to antennas, I'm currently using a Firestick fiberglass whip (not the Trim-to-Tune, but the one that you tune by turning screw on top) And, the coax is made by Wilson. Wilson also made my antenna mount.

Trying to get a decent ground plane is a nightmare. I'm limited to mirrors, as far as placement goes, and the whole cab is fiberglass. I tried running co-phased antennas, but I never could get them to tune right. I generally wait until I am out in the desert to do my antenna tuning; I can't find an open space to park the truck for tuning, on the east coast.

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[jdonovan]

I was trying to search for automatic tuners; Google keeps showing me tuning devices for musical applications. Is there another name for such a device?

feed this to google... w/o quotes... "ham automatic antenna tuner"

Common brands: LDG, MFJ

BUT, with a good, properly tuned 10m antenna there is no need for a tuner. Tuners are used mostly on the lower ham bands 3.5 Mhz, 7Mhz, where the band is fairly wide, and getting one antenna to cover the whole band is tricky. Or when you want 1 antenna to do double duty on more than one band. Its a compromise but everything in life is...


no ground plane is a bit of a problem, as is rig size. With a pickup/camper you can put a 2' square of steel sheet inside the fiberglass, but a 5' tall whip on a 13'6" rig is a non-starter.

I suppose you could do a on the frame mount of a whip antenna. Radiation to the rear would suck.... but it could work. Headache rack on your rig? or are you a van guy? Might be an option.

Depending on how much tune-ability the antenna has you might be able to tune a 11M CB down to 10M ham. but before I did that, I'ld look into:

The ham world has a firestick equivalent called a hamstick
http://www.mfjenterprises.com/Product.p ... =MFJ-1610T

[MarcSpaz]

I know you're working off the phone most of the time, so I grabbed a few links for you...

As far as the antenna position and getting that good reflective surface... I would still say but a whip, but get a mount that has the 4 element ground plane. Obviously the elements work best where they are tuned to the same length as the antenna itself, but that is not practical for a truck. What the antenna companies do is make the antenna 1/4 wave and the reflective elements will be something really short, like 1/48. That should help a lot.

As far as Google goes, try "automatic antenna tuner". There are kits you build and pre-built devices, so read the description before you buy.

Checkout the Ham Radio Outlet... http://www.hamradio.com/. They are the countries largest retail supplier. You can mail order or they have retail stores all around the country. http://www.hamradio.com/contact.cfm

As far as licensing goes, it really is very easy. You can get study materials from American Radio Relay League and there are a few sites with quality practice exams online. ARRL and QRZ are at the top of my list.

http://www.qrz.com/hamtest/
http://www.arrl.org/
http://www.arrl.org/licensing-education-training
http://www.arrl.org/getting-your-technician-license

Hope all this helps.

[SHMIV]

All this helps ALOT! You guys are awesome; I really appreciate it.

Yeah, I am a van guy; dry van and reefer. If I owned my truck, I would do some modifications for ground plane, but I am a company driver (owner-op is too risky a venture, these days). I actually did find a small, 4 element, ground plane, a few weeks ago. The little sticks are about 4 or 5 inches long. I haven't tried it yet. It only cost $10, so I figured it was worth a shot.

I reckon I'll have to buy a few things online. The stuff that you guys recommend isn't typically available at the truck stops. In fact, I'm beginning question the quality of truck stop radio shops. ..

I reckon I'll have to buy GF a couple nice things, lol. Maybe she won't fuss as much.

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