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Message |
    
The_bandit
Junior Member
Username: The_bandit
Post Number: 44
Registered: 8-2002
| | Posted on Thursday, October 05, 2006 - 2:56 pm: | 
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Ok, I know a Cobra 18 Ultra isn't worth putting a lot of time and effort into, but I've been playing around with one anyway. When I first got the radio, it seemed like it had a short. I checked the protection diode and it was ok, but when I would apply power it would cut out. I believe CH-1 (Choke Xformer) was shorted out. I have since wired around that and have gotten the radio to turn on.
My problems are, the Channel display is not showing anything, The radio is transmitting on 27.905MHz (out of band I know) regardless of whether the CH9 button is in or out and pushing the channel select button has no effect either. The radio seems to be receiving, but I do not know where.
I have been looking at available information on the PLL in that unit, and it seems that most functions are controlled via the pll. I'm thinking that the PLL may be shot, but before I try to locate one in a junk radio I thought I'd see what others on here thought.
The main reason I'm wanting to mess with this old 18 Ultra is that the PLL it uses is capable of memory channels and some other interesting features which I am going to try to install once I get the radio functioning properly.
I appreciate any help. |
Hotwire
Senior Member
Username: Hotwire
Post Number: 1863
Registered: 1-2005
| | Posted on Friday, October 06, 2006 - 11:48 am: |
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Bandit, I don't know if this will help any but here goes.
I have 3 china Cobra 148's that when I turn them on 95% of the time they will be RX and TX on a totally outband freq.
If I switch the on/off/volume knob off and on real fast a few times it will snap out of it! I know it sounds funny and to me I feel its ridiculous that 3 radios are doing this. So if that model Cobra you have has a knob that you rotate to power it on give it a try. I bet 2 cents it will work. If not? sorry man, don't you love the wonderful and exciting thrill you get from Cobra these days?. Will it come on this time? Or not? Who knows?  |
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