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<DIV>There has been deafening silence on this pic except for the reply from
Chris and an off-list, correct answer from David Crosthwait.
Congratulations again David! With the weekend coming to a close, I'll go
ahead and post the answer along with the "rest of the story".</DIV>
<DIV> </DIV>
<DIV>The control is the tracking adjustment on an AVR-3. The story behind
the control is really interesting and was told to me a while back by fellow list
member Bill Carpenter. Below is what Bill had to say.......</DIV>
<DIV> </DIV>
<DIV><EM>This control was added in the "massive retrofit", which I had to start
to correct all the problems.<BR><BR>The tracking control was there, but we
needed a front panel pushbutton, which turned on and off the very poor
autotracking. <BR><BR>I can't remember whether it turned the autotracking on and
off, or whether it just told it to track again!<BR><BR>The control came from the
Tektronix 7000 series scope, and I arranged to buy the controls from Tek, to
solve the problem, and not add another control as part of the
retrofit.<BR><BR>The original design by a well known industry servo design
engineer, would turn ON the dither, find track center, and then freeze that
position, and turn dither OFF.<BR><BR>This is fine for a long tape which was to
playback "to air". <BR><BR>The Hollywood post production marketplace had over 50
machines, and they found out that the source reels which would have many
"takes", a few seconds long, maybe 30 seconds at best would only track on the
first "take", and then mistrack on most of the others, since the Record machine
had been started and stopped after every take!<BR><BR>This all happened because
the Product Manager had no experience in the Hollywood marketplace, and was also
worrying about the Editing system we were going to buy from Central Dynamics in
Canada, but that's another long sad story, for another day!<BR><BR>We made the
Autotracking work, after the retrofit, with the control which I sourced from
Tek.</EM></DIV>
<DIV><EM>.........................</EM></DIV>
<DIV><EM></EM> </DIV>
<DIV>So, when Chris wondered if it might be part of a vectorscope, he
was almost on the right track! I have some of these controls on a Tek
7000 series instrument, but this pic was from an AVR-3 and was sent to me by
list member John Pommon. Thanks John! A bit of work in Photoshop
eliminated the "Tracking" label on the panel and turned it into B&W to hide
the panel color. The AVR-3 doesn't get much discussion on the list, but it
had been active recently so I thought it would be a good time for this
one. Next week, off in a different direction........</DIV>
<DIV> </DIV>
<DIV>Don Norwood<BR>Digitrak Communications, Inc.<BR><A
href="http://www.digitrakcom.com">www.digitrakcom.com</A></DIV>
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style="BORDER-LEFT: #000000 2px solid; PADDING-LEFT: 5px; PADDING-RIGHT: 0px; MARGIN-LEFT: 5px; MARGIN-RIGHT: 0px">
<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="FONT: 10pt arial; BACKGROUND: #e4e4e4; font-color: black"><B>From:</B>
<A title=dwnorwood@embarqmail.com href="mailto:dwnorwood@embarqmail.com">Don
Norwood</A> </DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A
title=quadlist@quadvideotapegroup.com
href="mailto:quadlist@quadvideotapegroup.com">Quad List</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Saturday, March 12, 2011 12:40
PM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> [QuadList] Weekend Mystery Pic
for 3/12/11</DIV>
<DIV><BR></DIV>
<DIV>For this weekend's challenge, identify the function of this control and
what machine it is on. As far as I know, it is the only control of
this design on any quad machine.</DIV>
<DIV> </DIV>
<DIV><IMG border=0 hspace=0 alt="" align=baseline
src="cid:AE182D3B1D454032B29D1E0AC6BD668B@dcidell2v2"></DIV>
<DIV> </DIV>
<DIV>Don Norwood<BR>Digitrak Communications, Inc.<BR><A
href="http://www.digitrakcom.com">www.digitrakcom.com</A></DIV>
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