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Message |
    
Cnmcake
New member
Username: Cnmcake
Post Number: 1
Registered: 3-2005
| | Posted on Friday, March 25, 2005 - 9:54 am: | 
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Just got my first CB radio in.
A MAXON MCB 30
Just Have some questions. I have it hooked up to a CB antenna i purchased at radio shack. I have it mounted to a Metal Awning on my house The antenna reaches to about were the roof drops off on the house. I have copper wire hooked to the mounting bracket on the antenna , wrapped around the metal awning and then goes down into a ground stick coming out of the ground. I have a little power supply from one of my sons old race car chargers. It puts out 15 volts at 300 mah's.
I can hear others on my radio just fine. I spent all day yesterday trying to get a radio check and did not get anyone to respond untill last night. Just wondering if I have done something wrong.
Thanks in advance for any help. |
Iluvrf
Junior Member
Username: Iluvrf
Post Number: 14
Registered: 2-2005
| | Posted on Friday, March 25, 2005 - 11:32 am: |
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Change your power supply. You need one that puts out 13.8v@3amps,13.8v at 3amps at the least. 5 amps would be better. Mobile antennas dont work very well mounted on the house. They need a good gorundplane to be efficient. |
Airplane1
Intermediate Member
Username: Airplane1
Post Number: 345
Registered: 5-2004
| | Posted on Friday, March 25, 2005 - 11:39 am: |
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I dont know about the awning mounted antenna but I think you should have a bigger power supply.
maybe 4-6 amp, thats what I have for just radio.
AP |
Red_devil
Member
Username: Red_devil
Post Number: 69
Registered: 10-2004
| | Posted on Friday, March 25, 2005 - 11:52 am: |
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Cnmcake,
Have you checked the SWR? You may also want to make sure that you DO NOT have any continuity between the radiating element and the metal awning. Also make sure that you DO have continuity between the male pin of the coax that goes into the radio and the radiating element. Also, check for continuity between the shield (outer portion of the coax plug) and the antenna mount (and awning).
If you have any problems with these checks, double-check all of your connections and solder points. This should get you started.
CEF447
Red Devil - 392
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Karatebutcher
Senior Member
Username: Karatebutcher
Post Number: 1929
Registered: 7-2002
| | Posted on Friday, March 25, 2005 - 12:09 pm: |
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What kind of antenna??? Do you know someone who has a radio or a handheld to listen to and have someone talk on yours?? |
2ec837
Member
Username: 2ec837
Post Number: 66
Registered: 12-2001
| | Posted on Friday, March 25, 2005 - 12:58 pm: |
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It sounds like you need a larger power supply.The charger you are using will work if all you want to do is listen.It will not supply enough amperage to transmit.
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Cnmcake
New member
Username: Cnmcake
Post Number: 2
Registered: 3-2005
| | Posted on Friday, March 25, 2005 - 4:59 pm: |
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"Change your power supply. You need one that puts out 13.8v@3amps,13.8v at 3amps at the least. 5 amps would be better."
Thanks for all the replys guys. I am wondering how do you tell what the amperage on the power supply is. For example, the one im using shows an output of 15 volts and 300 mah's. How did you all determine i dont have enough amps? Thanks again for all the info |
Bruce
Senior Member
Username: Bruce
Post Number: 2381
Registered: 9-2003
| | Posted on Friday, March 25, 2005 - 8:07 pm: |
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look at the fuse and remember most fuses are 1.5 times the current needed a 5 amp fuse meens 3 amps of current! |
Usa2112
Member
Username: Usa2112
Post Number: 54
Registered: 2-2005
| | Posted on Friday, March 25, 2005 - 8:50 pm: |
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buy one of those Victorian houses with the gutter all the way around.The added gutter will be helpfull!(somethin Jeff Foxworthy would say) |
Kid_vicious
Intermediate Member
Username: Kid_vicious
Post Number: 315
Registered: 9-2004
| | Posted on Friday, March 25, 2005 - 10:36 pm: |
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cnmcake, the power supply you have puts out 15 volts at 300 milliamps. meaning .3 amps.
if you look at the manual for the radio it will have a page called "specifications" or "specs". on this page it will tell you how much current the radio draws on receive and how much it draws on transmit. most radios draw about 3 amps on transmit. you might be damaging the radio by transmitting without enough current. think of it this way. with voltage, the power supply must put out the same ammount that the radio needs. too much or too little and the radio wont work right. with current (amps), the radio pulls the ammount that it needs from the power supply at any given time. so the power supply could be a 50 amp power supply, and the radio will still only draw three amps on transmit. so your supply doesnt have enough amps available to the radio for transmitting. look in the products section of this site, and you will find power supplies that will work for you.
as for the antenna, that antenna was designed to operate using the metal body of the vehicle for the groundplane. to recreate this on your roof, you would need a sheet of metal about nine feet square with the antenna mounted in the middle.
you need to do some searching and some reading in this forum. do keyword searches for these words and read as many of the posts as you can stand.
"SWR", "groundplane", "grounding", and "radials".
you will learn a lot.
what you are experiencing is one of the most common CB beginners problems. its the age old dilemma. "i dont want to put up that big ugly antenna, but i want to get out. i'll just buy a mobile antenna and use it at the house. how come im not getting heard?" im afraid there are only two possible outcomes from this problem. you'll either get so sick of not being heard that you'll buy an antron 99 and put it 20 feet above the house, or you'll get so sick of not getting heard that you'll put both the radio and antenna in the garage and sell them to someone like me in five years. lets hope you decide on the first option. we may poke a bit o' fun at the newbies, but we love turning new people on to our addiction... er' hobby.
good luck out there, and dont take anyone seriously. (except me of course!)
matt |
Tinker91
New member
Username: Tinker91
Post Number: 5
Registered: 2-2005
| | Posted on Friday, March 25, 2005 - 10:56 pm: |
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300 mil-a-amp is about 1/3 of 1 amp. a CB radio putting out 4 watts takes at least a 3 amp power supply. I would get a power supply. A 300 mil-a-amp charger is for charging a battery real slow. The more power that the radio is putting out over 4 watts requires more amps. Then make sure you check your SWR. I hope this helps.
Dave
CEF 515 |
Cnmcake
New member
Username: Cnmcake
Post Number: 3
Registered: 3-2005
| | Posted on Friday, March 25, 2005 - 11:35 pm: |
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ahhh so i would want a 14v power supply with about 3 to 5 thousand mah's then?
Awesome this clears up ALOT. thanks again. |
Tech808
Moderator
Username: Tech808
Post Number: 5337
Registered: 8-2002
| | Posted on Friday, March 25, 2005 - 11:42 pm: |
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Cnmcake,
Check out the Article I posted at the link below for more advice/help.
Which Power Supply Do You Need?
Hope this helps,
Lon
Tech808
CEF808
N9OSN
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Cnmcake
New member
Username: Cnmcake
Post Number: 4
Registered: 3-2005
| | Posted on Saturday, March 26, 2005 - 8:37 am: |
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"i dont want to put up that big ugly antenna, but i want to get out."
More like i cant afford the big ugly antenna!!!
LOL seriously though thanks for all the info. I def understand the power supply situation better. |
Cnmcake
New member
Username: Cnmcake
Post Number: 5
Registered: 3-2005
| | Posted on Saturday, March 26, 2005 - 9:46 am: |
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Also forgot to mention. I purchased this through ebay. Link was provided but was removed by mod. The reason i linked to it is because i guess this radio has been modded. It now keys at 5 watts and swings to 18. Dont know what this means. Have been told this is illegal but also been told it would have to key at 8 to be noticeable. Will I still want the same power supply as mentioned above? |
Coyote
Intermediate Member
Username: Coyote
Post Number: 166
Registered: 11-2004
| | Posted on Saturday, March 26, 2005 - 7:44 pm: |
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Cnmcake, the suggested power supply would still work even thought the radio has been "turned" up a bit. Don't worry to much about the "illegal" part, I know who and where you were told this. Welcome to the site and I'm glad to see you took my advice and came to this board. This site has a great bunch of VERY knowledgeable people and "actual" TECH's that KNOW what they are doing and MORE than happy to help. Save up some money, get that Antron or Imax antenna up and join the CEF Net and actually talk to these guys on Sunday's, myself included, maybe, if the skip will cooperate and that GOD awful interference I seem to ALWAYS have around Ch. 13 will go away for an hour or so at the right time.  |
Cnmcake
New member
Username: Cnmcake
Post Number: 6
Registered: 3-2005
| | Posted on Saturday, March 26, 2005 - 8:17 pm: |
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Thanks for the warm welcome and the invite. |
Kid_vicious
Intermediate Member
Username: Kid_vicious
Post Number: 318
Registered: 9-2004
| | Posted on Saturday, March 26, 2005 - 9:24 pm: |
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cnmcake, check out the "top one" bse antenna in the products section. it only costs 50.00 and is ups shippable. you'll like it!
matt |
