[time-nuts] Re; Motorola MC68HC11 Crystal (Robert LaJeunesse)

[Joe Leikhim]

Thanks Bob, Bob L, and Hugh.

I will look further into the exact specs of this 68HC11. Being this is a 
small densely packed portable radio, the circuit foils are very tiny, 
the stray capacitance is probably lower than typical design. Good point 
on using the div/4 pin to measure the clock and to isolate the pulling 
circuit. I will take a spare mother board and make a test jig for the 
capacitors. I will have to search for some 15 pf crystals as this is an 
unusual package.

I have in past changed these crystals with OEM parts without trouble. 
When they fail, by listening with a SW radio, instead of a clean tone 
you get what sounds like RTTY which I interpret roughly as "A quick 
Brown Fox Wants you To Change the Crystal Now Please". {:^) But now 
without a ready supply of qualified OEM parts and the cheap replacements 
not working on several radios, I am chasing myself.

-- 
Joe K4SAT