<html><body><div style="color:#000; background-color:#fff; font-family:times new roman, new york, times, serif;font-size:10pt"><div style="color: rgb(0, 0, 0); font-size: 13.3333px; font-family: times new roman,new york,times,serif; background-color: transparent; font-style: normal;"><span>In the 1970s, my father led an Advanced Development group at RCA Broadcast and one of their projects was to improve the lockup time for VTRs. Using a TR-70C, they developed a way to </span><span>achieve lockup within a time measured in frames, not seconds:<br></span></div><div style="color: rgb(0, 0, 0); font-size: 13.3333px; font-family: times new roman,new york,times,serif; background-color: transparent; font-style: normal;"><span> <br></span></div><div style="color: rgb(0, 0, 0); font-size: 13.3333px; font-family: times new roman,new york,times,serif; background-color: transparent; font-style: normal;"><span>
http://us.mg4.mail.yahoo.com/neo/launch?.rand=229377417&clmigstart=20110815<br></span></div><div style="color: rgb(0, 0, 0); font-size: 13.3333px; font-family: times new roman,new york,times,serif; background-color: transparent; font-style: normal;"><br><span></span></div><div style="color: rgb(0, 0, 0); font-size: 13.3333px; font-family: times new roman,new york,times,serif; background-color: transparent; font-style: normal;">It worked by applying an acceleration profile such that when the tape reached the correct speed, it was also in phase with house sync. I remember that to demonstrate it they had to manually hold the pinch roller against the capstan and keep the electronics in E-E until playback was locked.<br><span></span></div><div style="color: rgb(0, 0, 0); font-size: 13.3333px; font-family: times new roman,new york,times,serif; background-color: transparent; font-style: normal;"><span><br></span></div><div style="color: rgb(0, 0, 0);
font-size: 13.3333px; font-family: times new roman,new york,times,serif; background-color: transparent; font-style: normal;"><span>The group was in the Terminal Equipment group, not in the VTR group. When they demoed the system to the VTR group, it got the "NIH" reception: Not Invented Here. It never made it into any product.<br></span></div><div><br></div> <div style="font-family: times new roman, new york, times, serif; font-size: 10pt;"> <div style="font-family: times new roman, new york, times, serif; font-size: 12pt;"> <div dir="ltr"> <font face="Arial" size="2"> <hr size="1"> <b><span style="font-weight:bold;">From:</span></b> Don Norwood <dwnorwood@embarqmail.com><br> <b><span style="font-weight: bold;">To:</span></b> Quad List <quadlist@quadvideotapegroup.com> <br> <b><span style="font-weight: bold;">Sent:</span></b> Tuesday, August 21, 2012 2:38 PM<br> <b><span style="font-weight: bold;">Subject:</span></b> Re:
[QuadList] Servo Modes<br> </font> </div> <br>
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<div><font size="3">Hi Chris:</font></div>
<div><font size="3"></font> </div>
<div><font size="3">I have a VR-1200 that has a mod so that in H-lock mode, it
functions exactly as you have described for the RCA LineLock. It's a small
circuit board added in the control panel. Basically an NE555
timer controlling mode selection when Play is activated and the
servo selector is set for H-lock mode. </font></div>
<div><font size="3"></font> </div>
<div><font size="3">Don Norwood<br>Digitrak Communications, Inc.<br><a rel="nofollow" target="_blank" href="http://www.digitrakcom.com/">www.digitrakcom.com</a> </font></div>
<div><font size="3"></font> </div>
<div>----- Original Message ----- </div>
<blockquote style="BORDER-LEFT:#000000 2px solid;PADDING-LEFT:5px;PADDING-RIGHT:0px;MARGIN-LEFT:5px;MARGIN-RIGHT:0px;">
<div style="FONT:10pt arial;BACKGROUND:#e4e4e4;"><b>From:</b>
<a rel="nofollow" title="Chill315@aol.com" ymailto="mailto:Chill315@aol.com" target="_blank" href="mailto:Chill315@aol.com">Chill315@aol.com</a>
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<div style="FONT:10pt arial;BACKGROUND:#e4e4e4;"><b></b><font id="yiv30561100role_document" color="#000000" face="Arial" size="2"><font id="yiv30561100role_document" color="#000000" face="Arial" size="2"> </font></font></div><font id="yiv30561100role_document" color="#000000" face="Arial" size="2"><font id="yiv30561100role_document" color="#000000" face="Arial" size="2">
<div>RCA offered four modes of lock, Pixlock, LineLock, Switchlock, and
TW or Tone Wheel.</div>
<div><font size="3"></font> </div>
<div>Pixlock was the same as Automatic in the Ampex Machines. Linelock
starts in full automatic and then after lock reverts to the same as
Horizontal, Switchlock was vertical lock, and TW is the original servo
system.</div>
<div> </div>
<div>RCA did have the advantage with LineLock that it would always lock
vertically for a clean switch and then if there was a problem, have a fast
servo recovery.</div>
<div><font size="3"></font> </div></font></font></blockquote></div>
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