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Old 7th Mar 2019, 10:05 pm   #118
FRANK.C
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Join Date: Feb 2006
Location: Roscommon, Ireland
Posts: 732
Default Re: Hedghog standards converter

Chris
That's great thanks for letting us know.

SW8A and SW8B switch off the vision and audio modulators so they can be viewed individually on a scope to aid setting up the audio carrier level.

As far as I understand the audio carrier should be 6dB down on peak white.
What I do is hook up the scope with a 75R load to the RF out. The video out can be used to trigger the scope. Then switch Hedghog to display the grey scale and switch off the audio modulator. View the video RF noting the level of peak white. Then switch off the video modulator and switch on the audio modulator and adjust the audio carrier pot for 6dB down.
Adjust audio gain control to suit the audio level coming from the equipment supplying Hedghog.

Mark
Thank you. it's good to hear that your Hedghog's are working well.
I have plenty of the PCB's left. So just send me a PM letting me know how many you need.

Frank
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