> Sounds like Hsync values.... What PCB are you testing? Do these results show up on
> multiple PCBs?
>
> What does pin 7 on the LM1881N read?
I'm testing various PCB, I'm using two different frequency counter, an assembled kit and a low-cost professional counter (model VC3165 from Victor).In both I have bad or floating reading on PIN3 of the LM1881 IC.In this moment I'm testing a Legendary Wings bootleg PCB and I obtain on pin3 of LM1881 a floating value from 55 to 60 Hz.I thought V-Sync must be stable signal or I'm wrong?
P.S.
The VC3165 counter has also a 'period' function (instead of normally used 'frequency' function) and a 'gate time' knob but I don't know how to use them.
Edited by caius (01/04/11 05:57 PM)
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