Hi All,
FYI, running LM1881 sync pulse detector. NE567 tone decoder, as video switch for GB3GV analog, and has worked well for many years.
Since we have been playing with DVB-S sat boxes, have noticed, after some head scratching, the reluctance for the detector to operate and switch to Tx 100% of the time, the detector is after the default analog and digital inputs A/V switcher, so have now adjusted the 567 for sat boxes and analog sill works fine.
Frustrating when analog was fine and looking for reasons that 23cms and 437mhz digital was not making it!
73
Peter
Video Detector
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This forum is run by the BATC (British Amateur Television Club), it is service made freely available to all interested parties, please do not abuse this privilege.
Thank you
Re: Video Detector
Hi Peter,
Just wondering how you are detecting the video from a digital receiver?
There is always a valid video sync out of Digital receivers(not noise like analogue ones) hence the need for a digital Lock detector output on the receiver instead - this is not usually a standard feature.
I think Dave AJN posted a lock circuit for the BigSat digital receiver on the forum recently...
Rob
M0DTS
Just wondering how you are detecting the video from a digital receiver?
There is always a valid video sync out of Digital receivers(not noise like analogue ones) hence the need for a digital Lock detector output on the receiver instead - this is not usually a standard feature.
I think Dave AJN posted a lock circuit for the BigSat digital receiver on the forum recently...
Rob
M0DTS