04-04-2017, 06:46 PM
(This post was last modified: 04-04-2017, 06:47 PM by Murphyv310.)
Hi.
Well many 405 line sets had no AGC whatsoever!!!! Contrary to common belief people weren't thin in the days gone by, by the lack of AGC and alleged constant contrast adjustments.
The Pye V4 and some of its successors had gated AGC and a proper black level clamp, flywheel sync etc so these refinements were not just for 625 and negative modulation.
There also were many 405 line sets with no DC restoration or even a jot of of DC coupling and the pictures never had the milky look on BBC2 prior to duplication.
The Philips 210 had proper line gated AGC on both systems, had a decent IF that would resolve 5.25Mhz and still had this phenomenon of milkiness.
David Boynes also agrees with me on this that for some time BBC2 was poor then all of a sudden it cleared. I too have heard many engineers complain of the same issues and it's sudden improvement, also in a previous post as to the reason cited by Henry Chmiel from British Relay........ I rest my case....... Perhaps someone that actually was involved with BBC engineering at the time could clarify the situation
Well many 405 line sets had no AGC whatsoever!!!! Contrary to common belief people weren't thin in the days gone by, by the lack of AGC and alleged constant contrast adjustments.
The Pye V4 and some of its successors had gated AGC and a proper black level clamp, flywheel sync etc so these refinements were not just for 625 and negative modulation.
There also were many 405 line sets with no DC restoration or even a jot of of DC coupling and the pictures never had the milky look on BBC2 prior to duplication.
The Philips 210 had proper line gated AGC on both systems, had a decent IF that would resolve 5.25Mhz and still had this phenomenon of milkiness.
David Boynes also agrees with me on this that for some time BBC2 was poor then all of a sudden it cleared. I too have heard many engineers complain of the same issues and it's sudden improvement, also in a previous post as to the reason cited by Henry Chmiel from British Relay........ I rest my case....... Perhaps someone that actually was involved with BBC engineering at the time could clarify the situation
