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Dakota
Posted on Wednesday, November 21, 2001 - 8:00 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I have a cobra 148 gtl that has a very weak recieve and have tuned it to maximum recieve ... any one help me on that???
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307
Posted on Thursday, November 22, 2001 - 10:18 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Sounds like the RX was not tuned correctly. Do this and let me know...

USB RX = Peak L14 ,L12 , L10 , L9 , L8 and L7 in this order.

AM RX = Peak L15 , L13 , L3 , L6 , L5 and L4 in this order.

AM Rx if you do not have a scope , Trim L1 and L2 for best sound.
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outlaw 537
Posted on Thursday, November 22, 2001 - 2:44 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

DAKOTA IF after retune, you still do not have recieve, Replace the RF transistor. This tr. is marked TR 14 It is the first TR in the recieve circuit from ant. The trans. is a 2sc1674. good luck. outlaw 537
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Sg569
New member
Username: Sg569

Post Number: 5
Registered: 12-2004
Posted on Wednesday, January 05, 2005 - 11:55 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Dakota, hopefully you have NOT installed a 2sc1674 trans. It can actually produce noise in your recieve. Replace 2sc1674 w/ a 2sc2999 or a NTE 107. This trans. will produce higher amplification of weaker signals, AND give a lower noise floor. possibility of needing to adjust pots L4,L5,& L6. More L4&L6 than L5.
I am not a tech, just a cb'er who believes in passing on a good mod. 73's

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