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Old 9th Aug 2013, 10:38 pm   #9
Nymrod121
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Join Date: Apr 2012
Location: Worcestershire, UK.
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Default Re: Group Delay Correction on System A (405-lines)

I think you're right on the mark there, David. The only measurements I recall being done in respect of group delay were done on UHF plant only - use of a "Heucke" Group Delay Measurement Set was generally considered as being the most accurate way of doing it and the Senior Transmission Trainer at Wood Norton (Tony Larkham) had the procedure down to a fine art.

During a stint at Brookmans Park (BBC Transmitter Capital Projects Department), I remember reading a technical reference manual written by Nick Davies: "Group Delay, Ceefax and IF Mod. drives". Again, this covered the UHF network only. Nick's still around so I'll drop him a line and see if he can recall if there was any standard in respect of the VHF 405-line service.

I have to say that I'm inclined to agree with Ray's comment regarding the pragmatic approach ...

Regards
Guy
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Last edited by Nymrod121; 9th Aug 2013 at 10:50 pm. Reason: korekshun of spooling mistoks
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