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<DIV>Roger,</DIV>
<DIV> </DIV>
<DIV>Some excellent info from Park in the Ampex FEB's. <EM>However, a very
important caveat.....those papers do <STRONG>NOT </STRONG>reflect the load of a
machine with a venturi vacuum system. </EM> They are for the standard
machines with a vacuum pump. Ampex didn't use the venturi vacuum on any of
the VR-xxxx models although many were updated with the Merlin mod kit.</DIV>
<DIV> </DIV>
<DIV>So, be aware that a venturi equipped machine requires about twice the
volume of air, almost 1 cfm as I stated in my earlier reply. Actually,
it's typically a bit over 0.9 cfm, so rounding gets you to 1 cfm. There
are a number of compressor options that will deliver what you need, and there is
a used market because of their applications in industrial, medical and
instrumentation, so you can often find a compressor for much less than new cost
if you are willing to wait for the right unit to come along. </DIV>
<DIV> </DIV>
<DIV>There are also some variances in the prescribed head operating
pressures. I'd be interested to know what the folks that are rebuilding
heads specify today. I've always gone by the settings that I listed
earlier from the Ampex manual, but perhaps slightly higher is OK.
Certainly better than too low I would think!</DIV>
<DIV> </DIV>
<DIV>Don Norwood<BR>Digitrak Communications, Inc.<BR><A
href="http://www.digitrakcom.com">www.digitrakcom.com</A></DIV></BODY></HTML>