[DSP-10] Having PLL Problems

Mon, 4 Aug 2003 16:02:56 -0700

I also think you have a counter problem. If you monitor the voltage at R105
and run udiag3, this voltage should vary from 0.something to 4. something as
it tunes from 124.3 to 128.3. The voltage should also change as you tune
L102.

Larry (I just got mine working 2 days ago)
----- Original Message ----- 
From: "Christopher Michael Best" <[email protected]>
To: <[email protected]>
Sent: Monday, August 04, 2003 1:03 PM
Subject: [DSP-10] Having PLL Problems

>
> 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
>
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