This article by Neville Thiele of the Australian Broadcasting Commission was the prototype on which the article in "The Radio and Electronic Engineer" Vol 40, No 4, October 1970 was based. There were some changes to this article prior to its republication, notably the captions to some diagrams which were simplified and reduced in verbiage - which in my opinion reduces some of the clarity of Neville's original descriptions. Hence the reason for our posting of the original Australian article, which until now was probably only available to readers in Australia.
With the author still living and publication having occurred only 40 years ago, I was unwilling to post this article in the open access part of the forum. Here, where only registered members of the NBTVA or registered members of the forum can gain access, seemed more appropriate in deference to the author and the original publishers (IREE Australia).
The posting occupies an aggregate of 16 pages, 2.7 MByte of cache, the minimum to which I could compress this text in .gif format while still retaining legibility. Attempts to convert to .jpg resulted in a complete scrambling of legibility.
Please refer to discussion headings on "aperture correction" for older texts on the subject (1927 - 1953) and for circuits adapted from this posting for usage in 32-line NBTV.
Chris Long VK3AML.