cobra 2000

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smoke blower
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cobra 2000

#386444

Post by smoke blower »

I have a cobra 2000 that has lost its output. It was working then all of a sudden the power dropped slowly then that was it. the final checks good I have pa and receive. It keys up my test radio and has good modulation coming through it just no wattage output
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Re: cobra 2000

#386445

Post by sonoma »

you did not say if it has SSB working or not. here is what happens if it is only AM with no carrier. the trans may be bad also causing this. forgot to tell you the main board is the same as the 148, I know yours is the 2000.

http://downloads.cobra.com/CB ... B10016.pdf

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Re: cobra 2000

#386447

Post by smoke blower »

Same thing on ssb modulation is good on my test radio but no wattage output pa works great also. I installed a brand new final and still the same

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Re: cobra 2000

#386450

Post by MDYoungblood »

Let me get this a little clearer, you can hear yourself on your bench radio (SSB) but the bench radio isn't showing any signal swing? Can you hear yourself on AM as well? Check the power to the driver or did you replace it as well?

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Re: cobra 2000

#386452

Post by smoke blower »

Yeah it pegs the needle on the bench radio and loud audio on am and ssb. it is just that the cobra 2000 isn't putting out any power at all no dead key nothing on the watt meter
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Re: cobra 2000

#386455

Post by smoke blower »

I will check the voltage on the driver and get back to you in a bit I had a bunch of company come in
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Re: cobra 2000

#386461

Post by smoke blower »

I am not sure what the readings are supposed to be but looking at the solder side of the board on the final I have 0.45v on the right leg 13v on the center and 0 on the left leg. On the final right leg I have 0.16v center leg I have 13v left leg 0 that is on tx

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Re: cobra 2000

#386481

Post by smoke blower »

Are these wrong voltages

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Re: cobra 2000

#386489

Post by sonoma »

use the cobra 148 voltage chart to see what the voltages should be. what I found from the 2000 radio all the voltages are on the schematic and you say you can not rad the schematic.

http://downloads.cobra.com/CB ... ltages.pdf


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