[TenTec] Paragon logic board

[Bob McGraw - K4TAX]

As a general rule, electrolytic caps decrease in value as they age.  That 
being the case here, the value could now be 1/4 of its original value and 
which makes the simple RC timing just too fast for the system to load and 
boot.  A  new cap or one that's 50% larger might just solve the problem.

73
Bob, K4TAX




----- Original Message ----- 
From: "Don Rasmussen" <wb8yqj at yahoo.com>
To: <tentec at contesting.com>
Sent: Thursday, August 22, 2013 2:50 PM
Subject: [TenTec] Paragon logic board


On my Corsair II the microprocessor and the crystal were both okay, it was 
the electrolytic capacitor used to boot the microprocessor at power up that 
had drained itself dry mounted on the pcb.

I could hear the crystal oscillating with an external receiver and a make 
shift probe but had no activity at the mpu.


>If you buy a Crystal, then I'll bet you $5 it's the cpu!  (hi) >

>> 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. >>  >> Bob, K4TAX
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