Electronics > RF, Microwave, Ham Radio

Driver stage in CB radio

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Jane:

My understanding of a driver circuit is that it provides an input voltage for (a  final) power amplifier.
In a service manual for a CB radio there is a test point marked TP1 driver. Does it mean that it is an output of that driver stage and an input for a power amplifier?
Is there any clue how to find out, in schematic, where  such a driver circuit is?
Being a newbie with CB radios, can you recommend a website/literature where I can learn more technical details?
Thanks

tkamiya:
If you can post a schematic diagram, I can try to help you out.

TP stands for Touch Point.  It's a test point.  So it doesn't really mean anything.  Since it says driver, it probably belongs to the stage you are wanting, but what the signal entails, there is no telling. 

A simple CB radio usually has a final stage consist of one transistor.  One before that is a driver.  Again, with schematic, I and many other here can help you out.

Jane:
Thank you for your reply
I uploaded the schematic.
it is on page 5
Please check.
Thanks

tkamiya:
OK, got it. 

Q4 is the final stage.  You can tell this because it comes before output filter.
Q6 is the driver stage.
Q3 is acting like a switch depending on status of Q13

I'm amazed a CB radio comes with such a nice documentation.

Jane:
Thank you for your explanation of Q4.

I  also understand that Q3 is acting like a switch depending on status of Q13. In other words when I want to transmit,
TX_UNLOCK is 0V ,then Q13 is closed, and Q3 should be open. Am I right?

But how do you know that Q6 is the driver stage?

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