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Radio Make and Model: Cobra 2000 GTL
PCB Number: PCB-497
PLL Number: 8719
Test gear available:

Symptoms: Frequency locked

What is working:
By switching the channel selector is always transmitting and receiving the channel 1
When I select USB or LSB the frequency of transmission and recepição lost.
On AM transmit and receive 100% but always in 26,965.

What has been tried:
Changing the PLL but I could be leaving the radio mute on pin 1 voltage is 1.8V to 2.25 V, the former is 4.25 and the radio receives and transmits at the new has RX and TX.

Did it suddenly happen ?:
his radio has been changed long ago and operated 100% execelente staff convey a clean and stable, to expand the channels and the crystal was changed to 11.1125.

Anything else that may be of help?:
verything started with the lack of stability of the frequency, the radio was stopped for about 8 years now when I turn it on the frequency was running, and told me what could be the PLL.

I guys, help me!!

What medition of PLL mb8719 in cobra2000GTL?

the radio has the same symptoms with and without the PLL in the socket.

any ideas?

I could repair my old radio!
The long long and long search, problem is PLL!, but others exists with x1 10.240 not ranged replace it and d31 diode IN4148 replace it
Adjusts OK
But frequency meter not ok, em AM 100%, in LSB or USB it present 347743 or something like.

Any idea!!!


Thanks.
Carlos