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New here. Need 29lx with kl203p info

Gypo

New Member
Feb 22, 2017
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Hello all. First post here. New to radio tech, been reading up on it last couple weeks.

I am a logger and work in remote locations. We use cb's as communication quite a bit, especially to avoid collisions with log trucks on single lane gravel roads. The only time I really turn the cb on is out in the woods.

Have a cobra 29 lx, 102 whip mounted on top of pick up headache rack. Works good. Thinking of adding rm kl203p for more range. Have read I need to lower dead key. I seldom key up for more than 10 seconds, and almost never run a cb in populated areas.

Will amp last used this way without deadkey mod?

Do I need to worry about bleed over (or anything over driving the amp does) if I only run it in these areas?

Can I have a high low switch put in this radio? (Deadkey) If so can it be run to the 9/19 button?

Id like to just hook it up and run it, but thought Id ask her first. Theyre cheap so if I can run it without deadkey mods and get a couple years out if it Im good with that.

Sorry for long post, and thanks for the help.
 

You will need to lower the dead key. 3-4 watts of dead key will be way too much!! .25-2 watts is where you may need to be. You can have a variable power added to the where the Delta Tune knob is now. Don't use the factory knob, but rather get one that will handle the job. Any good tech can do this for you. Then you can lower your dead key to whatever is needed to make the amp key up to about a 20-25 watt carrier max. Or 1/4 of the total output on AM. So if it does 100 watts pep, a 25 watt carrier or dead key would be good.
Also make sure your antenna system is best as it can be!! Having a 102" whip mounted on top of a headache rack may not do as well as an antenna mounted in the center of the roof with a good hard mount. A Sirio 5000 performer or even your 102" whip with a spring would work well hard mounted in the middle of the roof. You need metal under your antenna. The more the better.
Then bonding all vehicle body parts and exhaust to frame is a good idea as well as checking all the factory grounding for good connection. Use NO-OX Special "A" grease on all connections. And make sure all paint is sanded down around area where grounds meet the frame and/or body. Not a large spot, but enough to make sure the bolt/screw is not being covered up by paint/rust. Also bond your exhaust system to the frame.
Use good quality wire for the radio and amp. And go directly from battery with the + and make the ground wire as short as you can and take it to a good frame ground. Either a seat bolt or under the dash, at the steering column seems to be a good place to ground at. Some will to go directly to battery with both the positive and negative wires, I have always been taught to go to the frame. 6 of onez, half dozen of the other!! Either way you need to make sure all equipment is well grounded. Both radio and amp can also have the chassis grounded. If it creates an issue remove it.
Then the antenna will need to most likely be re tuned after all the bonding of the vehicles body panels and such.
Also, make sure to get a good Hard Mount if you decide to go this way. It takes a small hole in the roof that can be covered when or if the mount needs to be removed. Either using a special plug, or by just buying a hard mount like a Wilson gum drop type mount. That way you don't have to leave your good mount on the vehicle if you ever get rid of it.
Many don't like drilling their truck roofs as they think it will decrease the value of the vehicle a bunch or something. Not so. A simple fake mount or even a small antenna like what is being used on a lot of small vehicles today would work well too. These are all JMO's.
If you want to just leave your setup the way it is, just make sure your VSWR (SWR) readings are below 1.3:1, as those amps that you're looking st don't like a bad match on the antenna system.
As far as hard mounts go, Breedlove is a pretty good one. Couple one of these with either a 102" whip and and a small riser for tuning and length, or an HD 4"-6" spring. Either way the mounts (Breedlove), are very well made. Yes they cost a bit, but you get a quality product!! And the Sirio 5000 works well with the 3" one hole Breedlove mount. Or the larger 4" and above as well. But those require more holes I beleive. Anyhow.
The amp you speak of, the RM Italy KL203P, definitely needs to have the dead key dropped on a factory radio to make it work correctly.
Yes, it might, and I say this with much caution, might work with a stock radio, but not for very long I would think, and also it would get hot fast!!
I recommend adding a fan to one anyway. Even with the dead key lowered, it can still get pretty warm. Best to keep it cool as possible.
Enough BS. Hope this helps. I know it's long, but there is a lot to cover with a good install. And I just scratched the surface with what I wrote!! Have a good day.
 
welcome aboard, 222 is right about the little amp. it will need a lower dead key or it will only last a few key ups with 4 watts put into it. I have one I have used off and on since about 2000 and it still works fine. I just make sure my antenna and radio are set right . a high drive amp is a little bigger and cost a little more but you would not have to drop the dead key. the little 203 amp does very well as long as it is getting a 1 to 2 watt dead key. when the dead key is set the amp should only put out about 25 watts to keep it working for a long time.
 
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Gypo it is very easy to drop the dead key of the cobra 29 radio. all you have to do is pull the JP36 jumper by the final and driver and install a 220uf cap in the holes left from pulling the jumper wire. put the cap with the negative towards the back of the radio. on the solder side of the board install a 75 to 100 ohm resister across the cap legs and you are done. a 75 ohm will give you a higher dead key than the 100 ohm so you just will need to see which one you will need to get the dead key down to suit the amp. the radio will swing to the full potential and you do not need to have a high and low switch in it to do what you are wanting. this mod will even give you a little more modulation to help push through all the other stock radios out there.
 
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Thanks a bunch fellas.

Got my swr down to 1.1-1.2 on an astatic meter today.

I think I would like a variable dead key on a high low switch, or maybe have a variable marked on the low side.

I live in Oregon and have looked for local cb shops and there seems to be none. Who should I take my radio to? I could always mail it if someone has a suggestion of where?

Thanks fellas.
 
There are some good techs out West. Not sure about your particular state, (Oregon), being one that I recall having any shops or techs that are worth a darn. Might try Doug's Custom CB,s, Key CB shop, and I'm pretty sure that that are more of me than I can think of at the moment. Robb, Sonoma, and a few other gents may be able to be of more assistance than I. I live on the East Coast of the USA. FL to be exact. So I don't know many shops put that way. I'm sure the 2 I listed can accommodate your needs just fine, just not sure of cost.
Like Sonoma said, it's much easier to just lower dead key, but variable will allow better fine tuning of the amps carrier or dead key.
At any rate, hope this helps. And have a great day.
 

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