<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML><HEAD>
<META http-equiv=Content-Type content="text/html; charset=iso-8859-1">
<META content="MSHTML 6.00.6000.16825" name=GENERATOR>
<STYLE></STYLE>
</HEAD>
<BODY id=role_body style="FONT-SIZE: 10pt; COLOR: #000000; FONT-FAMILY: Arial"
bottomMargin=7 bgColor=#ffffff leftMargin=7 topMargin=7 rightMargin=7>
<DIV><FONT size=3>The mod that Chris describes will certainly work, at the
expense of having 625 operation (which was usually not a concern), but there are
some other considerations that I'll address in reply to his other post.
Another version of this same approach could also be used for 625 machines that
didn't need 525 operation.</FONT></DIV>
<DIV><FONT size=3></FONT> </DIV>
<DIV><FONT size=3>Don</FONT></DIV>
<BLOCKQUOTE
style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px">
<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A title=Chill315@aol.com href="mailto:Chill315@aol.com">Chill315@aol.com</A>
</DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A
title=quadlist@quadvideotapegroup.com
href="mailto:quadlist@quadvideotapegroup.com">quadlist@quadvideotapegroup.com</A>
</DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Sunday, August 23, 2009 10:59
AM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> [QuadList] VR-1200 Capstan
Oscillator Mod for Course and FineAdjustment Pots</DIV>
<DIV><BR></DIV><FONT id=role_document face=Arial color=#000000 size=2>
<DIV>VR-1200 B Series Inter-Sync 60 Hz Capstan Oscillator Modification</DIV>
<DIV> </DIV>
<DIV><BR>This was given to me by someone a long time ago. It made life
simpler.</DIV>
<DIV> </DIV>
<DIV>The capstan Oscillator is difficult to set and is critical for assemble
edits. It sets the free run speed for the capstan. There is a
simple modification that will provide the user with a course and fine
adjustment pot for the oscillator.</DIV>
<DIV> </DIV>
<DIV>Remove Board 13 from the Inter-Sync.</DIV>
<DIV> </DIV>
<DIV>Find R-78, the 625 Capstan Frequency adjustment. </DIV>
<DIV> </DIV>
<DIV>Lift the wire that connects the end of the pot to Q-12 Collector.
This is the end not connected to R-60, a 300K resistor.</DIV>
<DIV> </DIV>
<DIV>Attach wire disconnected to the End of R-20 that is not connected to
R-38, a 20K resistor.</DIV>
<DIV> </DIV>
<DIV>Reinstall board</DIV>
<DIV> </DIV>
<DIV><BR>TEST and Setup</DIV>
<DIV> </DIV>
<DIV>Center R-78</DIV>
<DIV> </DIV>
<DIV>Adjust Capstan Oscillator using R-20.</DIV>
<DIV> </DIV>
<DIV>From now on only use R-78 for Capstan Frequency Adjustment unless pot is
near the end of range. Then re-center and set Oscillator with
R-20.</DIV>
<DIV> </DIV>
<DIV>R-20 is now the COURSE adjustment and R-78 is the FINE
adjustment.</DIV></FONT>
<DIV class=aol_ad_footer id=e66e1d4d38e140b35426bba4a693badb><BR><FONT
style="FONT: 10pt arial,san-serif; COLOR: black">
<HR style="MARGIN-TOP: 10px">
</FONT></DIV>
<P>
<HR>
<P></P>_______________________________________________<BR>Please trim posts to
relevant info when replying!<BR>Send QuadList list posts to
QuadList@quadvideotapegroup.com<BR>Your subscribe, unsubscribe and digest
options are
here:<BR>http://mail.quadvideotapegroup.com/mailman/listinfo/quadlist_quadvideotapegroup.com</BLOCKQUOTE></BODY></HTML>