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Biskybabyusa
Junior Member
Username: Biskybabyusa

Post Number: 31
Registered: 11-2006


Posted on Saturday, February 10, 2007 - 9:01 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Does anyone know if all Cobra 2000 Freq counters are interchangeable ? Mine is showing erratic numbers and may not ba able to be repaired. Do all Cobra 2000's use the 8719 PLL ? Mine has that one but a friend says his has the 8734 PLL. I have a chance to get a junked out 2000 and am thinking about scavenging the freq counter out of it if it will work. Thanks
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Kid_vicious
Senior Member
Username: Kid_vicious

Post Number: 2388
Registered: 9-2004


Posted on Wednesday, February 14, 2007 - 12:30 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

wassup,

yes, all of the freq. counters should be interchangeable.

what is your freq. counter displaying?
is it jumping around?
is it going back and forth from the correct freq. to 92.20000?

all cobra 2000's had the 8734 chip fromt the factory.
if you wantedt to mod your 2000, you had to buy an 8719 chip and use it.
nowadays you cant buy the MB8719 chip anymore so you'll have to find a grant XL, LT, or a 148gtl to scavange one from.
get teh junked 2000 and keep all the parts.
there are lots of parts in that radio that are only for it, and can fetch a good price on the auction site.

most likely your freq, counter can be repaired.
matt
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Biskybabyusa
Junior Member
Username: Biskybabyusa

Post Number: 33
Registered: 11-2006


Posted on Thursday, February 15, 2007 - 9:54 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

thanks, Kid. IT shows 92.333000 and umps !!
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Kid_vicious
Senior Member
Username: Kid_vicious

Post Number: 2396
Registered: 9-2004


Posted on Thursday, February 15, 2007 - 11:22 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

go to this link and scroll down until you see the TECHNICAL BULLETIN for the 2000gtl.
http://www.geocities.com/cobra269/mods.html,
this was a common problem.

also, you should replace all the electrolytic caps in the freq,counter. this will make it much more stable.
FET501 and FET502 might need replacing also.

be careful when soldering on this PC board.
it is not like the main PC board in the radio.
it is double sided and plated through, which means that you will need a special desoldering iron to "suck" the solder out of the holes.
if you dont do it right, you will surely ruin it beyond repair.
do not try to use the little red squeeze bulb from radio shack, unless it is the one that comes with the solder sucker iron with the hollow tip.
you should be able to find the right kind of hollow tipped soldering iron on the auction site for less than 20.00.

try the service bulletin first, then the caps, then the FETs.

myself, i would do the caps anyway, but thats me.
good luck,
matt
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Biskybabyusa
Junior Member
Username: Biskybabyusa

Post Number: 34
Registered: 11-2006


Posted on Friday, February 16, 2007 - 9:47 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Good plan ! I have a good de-soldering iron. Thanks a lot for the great info Matt. I will check out the bulletin.

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