[DSP-10] Having PLL Problems
Christopher Michael Best
[email protected]
Mon, 4 Aug 2003 15:03:35 -0500 (CDT)
Thanks for the recent discussion, and solutions on the serial
clock pulse being rounded. I used two inverters on a 74HC04 to square up
the signal, and now it appears that my serial problems are solved.
(Another step closer to getting on the air!)
I am still having some problems with both PLL in my system. Both
of the PLL's are outputting 0hz (No output) on my frequency counter. Both
of the synthesizers are recieving a clean 10MHz signal from the Epson crystal
oscillator. Voltages on both synthesizer appear to be alright, 4.72V on
the drain of Q101, and 3.67 on the drain of Q4. U107, and U108 voltages
are as stated on Bob's PLL diagnostics sheet. Pin six of the U6 op-amp is
on the bottom rail at .49V.
Is it possible that both of my J310 FETS are dead? They were mailed to
me in a regular envelope, so they might have been damaged in transit.
Thanks,
Christopher M. Best