| Author |
Message |
    
Kwhubby
New member
Username: Kwhubby
Post Number: 1
Registered: 12-2004
| | Posted on Friday, December 31, 2004 - 3:58 am: | 
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Hi, I just set up a mobile 11 meter rig with a lil wilson antena a kl200p amp and a cobra 148 gtl radio. It seems to be working fine, but I am quite new to this and have some questions. First, right now i just have everything loosely connected running off the cigarette lighter (fused for 20 amps, working fine) and I am wondering if I need to ground the case of my radio for better performance. I’ve read something somewhere about grounding the antenna and the radio or something but could somebody explain this to me? Another question I have is about a seemingly odd ssb performance: When I transmit in ssb (lsb or usb) with the amp on (in ssb mode) it seems like maybe very little power is coming from the radio because the transmit relay on the amp seems to flicker when I talk less I move the mic gain way up. Is this normal or is something wrong? do I need to tweak something? I did significantly turn the am power down (without a watt meter just guessing with meter on the front of the case) in fear of harming the transistor but after transmitting for a few minutes or so with the mic gain up all the way the amp doesn’t even get warm were the transistors are mounted, do I have the output power down lower then necisary? I still have yet to do some more tests to see what kind of range im getting and to test to see if the ssb is transmitting well. Thanks for any help or suggestions. |
Mdiver
Intermediate Member
Username: Mdiver
Post Number: 199
Registered: 11-2003
| | Posted on Friday, December 31, 2004 - 11:06 am: |
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Run your Amp to the Battery
and your cobra to the cig lighter |
Pig040
Advanced Member
Username: Pig040
Post Number: 619
Registered: 7-2003
| | Posted on Friday, December 31, 2004 - 11:18 am: |
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I agree diver, no way is the amp performing at its best run through the cigarette lighter. I learned that the hard way, sold a perfectly good amp, thinking something was wrong with it. The guy I sold it to wired it direct and it was a screamer.
Rich |
Dx431
Advanced Member
Username: Dx431
Post Number: 959
Registered: 2-2002
| | Posted on Friday, December 31, 2004 - 11:52 am: |
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Ground everything. Radio, amp and ant. Go directly to the battery with the radio and the amp and use 8-10 awg wire. Fuse at the battery.
The amp on ssb is keyed by your audio(voice), the clicking sound is normal. |
Kwhubby
New member
Username: Kwhubby
Post Number: 2
Registered: 12-2004
| | Posted on Friday, December 31, 2004 - 3:56 pm: |
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AHH thank you everyone, I dont have any 8-10 awg wire but I do have a big roll of 14 awg, would it work to double the 14awg by twisting it together (so have 2 lines), the similar thing is done sometimes with speaker wire. Since the outside of the coax is connecting the cases of the radio, amp, ant is it necisary to run seperate grounding wires to each unit? I just gotta figure out how im gonna get wire to the battery in this car. |
Dx431
Advanced Member
Username: Dx431
Post Number: 960
Registered: 2-2002
| | Posted on Friday, December 31, 2004 - 5:19 pm: |
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The coax is not a sufficent ground. A seperate ground for each component should do the trick. |
Gumball
Junior Member
Username: Gumball
Post Number: 39
Registered: 10-2004
| | Posted on Saturday, January 01, 2005 - 12:04 pm: |
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kwhubby:
If you consider the co-ax sheilding braid a ground, you are asking for RF interference.....
6 or 8 gauge braided wire is available from Radio Shack, electrical supply houses, etc - much easier and better than "braiding" wire.....and make sure the end connectors are soldered.
There is a difference between "power ground" and "RF ground".
When running an amp, extra grounds (if not mandatory) are a VERY good idea. I would ground the cases of both radio and amp to the chassis.
It is ok to run power from the fuse block (or lighter plug) for the radio, but amp + and - should be run directly to battery. |
