[TenTec] OMNI VI Model 563 -- no digital readout (Peter Bertini)

[Gregory Smith]

(Peter Bertini)
Hi Peter,

Thanks so much for your troubleshooting suggestions.

U12 74HC74 working. Pin 5 = 5Mhz output & pin 9 = 10Mhz output

U13 MC145170 (PLL) some odd things happening. Digital pulses, unequal pulse width, on pins 14 & 15.
Pin 7 (Clk in) +/- 200mV sinewave, pin 8 (D out) - no digital signal.
The data sheet talks about this part being programmable. I'm not familiar with this part at all.  I expected to see a digital pulse on pin 7.

Do you know the level of the sinewave requirement for the uP pin 19 (xtal 1)?  Since the 74HC74 & the uP obtain the clock from transistor Q2, I assume it's okay.

Any additional help in chasing this issue would be much appreciated.

Greg W2GLS (Gregory Smith)