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Old 01-19-2011, 11:25 AM
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Ok, back to Getting to know you way around the radio

Please excuse the crude photo I am attaching.
As you can see I have divided the radio into 4 main groups. Remember, some sections do over lap with other sections. But that is fine for now. Mostly all radios today are built under this design. You will see a few that is a little different. But when you get the understanding of where things are in the Cobra 29 you will easily be able to identify other boards. In my first post is a schematic with certain area's labeled. Take the time to open that schematic and find the labeled sections on the schematic. That will give you a better understanding as to where the parts are in relation to the schematic.

PLL
In this area you will find the PLL chip and it's supporting components, 10.240 reference oscillator, The VCO and supporting components. You will also find the 5 volt regulator in this area.

Output and TX mixing
In this area you will find the begining of the transmit stage, the transmit mixer, predriver (buffer), driver , and the final

Audio and modulator
In this area you will find the audio stages, the AMC stages and modulation limiting circuits, voltage regulators for TX & RX functions..

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