[TenTec] Paragon logic board

[Mike Bryce]

Bob and the group,

The project continues, no joy insight, the microprocessor oscillator is not running.

So, is it the Crystal or the microprocessor?

The Crystal is not hard to come by. EBay has them 10 for $15.

Right now, it's a crapshoot 50-50 chance it could be the microprocessor or it could be the crystal.

I wonder, if I were to take a 4 MHz crystal And solder it in the place and see if it would oscillate. I realize it would not work correctly but  that would show if the oscillator inside the microprocessor is operating.

Ten tec has no parts in stock. I called. 

Mike wb8vge

Sent from my iPad

On Aug 20, 2013, at 10:31 PM, "Bob McGraw - K4TAX" <RMcGraw at Blomand.net> wrote:

> Yea, the board is a pain to pull.  My schematics are at the shop, and I'm not so I can't say exactly which designator is the timing cap.  It is on the RESET line of the MP to ground and has a value of R to the 5 volt line as I recall.  This is not the same as the external reset line to the switch on the side of the radio.
> 
> As power is applied, be it from activation of the switch on the front panel or from the power supply, there is a reset pulse generated by the timing cap and resistor that resets the microprocessor, but only after the operating parameters are loaded.  In other words, the MP starts with a clean load of data.
> 
> Worth a try.
> 
> 73
> Bob, K4TAX
> 
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