Copper Talk » Ask The Tech » Radio's Mobile » Archived Messages » Unlocked PLL on Cobra 29 LTDwx « Previous Next »

Author Message
Top of pagePrevious messageNext messageBottom of page Link to this message

Jose22
Posted on Monday, April 08, 2002 - 11:23 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)
had a cobra 29LTDwx brought in that had no voltage on lock pin of PLL. (unlocked). Owner claimed he tuned radio last night and worked good. This am radio did not work.. Now only has small static. NO TX or RX. Suspected he unlocked by screwing around with VCO . CAN with wax showed it. Started to retune cans to get proper output on Scope and correct voltage but can tuning had no effect. Took heat gun to melt off great deal of wax around IC2 (TA7310-1) to get at test point better, and while hot radio started to RX. When cooled in 20 seconds, quit again. Looked for breaks, resoldered IC2 , no response. Got any answers?

Thanks Jose22
Top of pagePrevious messageNext messageBottom of page Link to this message

Jose22
Posted on Wednesday, April 10, 2002 - 10:02 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)
Hey, guys, I know someone knows. What about you Tech?
Top of pagePrevious messageNext messageBottom of page Link to this message

307
Posted on Thursday, April 11, 2002 - 3:41 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)
Yup..Replace the 10.240 Ref Crystal...

Bill
Top of pagePrevious messageNext messageBottom of page Link to this message

Jose22
Posted on Thursday, April 11, 2002 - 10:01 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)
Ref Crystal is dead on according to Frequency counter. I thought the heat affected it but when in cool state it shows correct frequency.

Add Your Message Here
Post:
Username: Posting Information:
This is a private posting area. Only registered users and moderators may post messages here.
Password:
Options: Enable HTML code in message
Automatically activate URLs in message
Action: