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<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">This memory has invoked my
nightmares of the TRT Tube modulator. The matching/seasoning of tubes to
settle that sucker down took days and then it would run for >3 months
unless some fool changed a tube. The Servo Amps, seldom a problem but
regular application of the traditional rubber hammer in tool kits (arcing
gas tubes) How many times has someone asked you what that hammer was for?..We
have come a long way baby!</SPAN></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"> </P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">I think the Evolution (State of the
Art) of Videotape best explains the head wheel transition. Ball bearings
& brushes worked just fine in that era</SPAN></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"> </P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">A) Low Band Mono TRT1B & the
color version TRT-!C Tube era with the first RCA Transistor Proc-amp (Sync
& Video level) The picture in advert is a TRT-!B showing only 3 racks of the
5 rack</SPAN> <SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">machine. The
TRT-1C was 7 racks</SPAN></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"> </P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">B) The TR-3/4, TR5, TR22 were
transistor versions using Geranium 2N404 & 2N585. The head wheel Vacuum
was</SPAN> p<SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">art of the Blower
Assembly (Noisy bugger) these machines where Low Band Mono and Color and
upgrading kits may have been offered but not the best option. RCA did switch
head panel pickup to transformer but Air bearings?? I don’t think that would
have improved performance of those Machines, but RCA would sell any upgrade
& have a field guy install it. <?xml:namespace prefix = o ns =
"urn:schemas-microsoft-com:office:office" /><o:p></o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"> <o:p></o:p></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">NOTE:<SPAN
style="mso-spacerun: yes"> </SPAN>7.5 IPS was not a normal Broadcast
feature (Bandwidth). I think some 8 head military data versions
played in those</SPAN> <SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">regions. The features like “Pilot
tone” weren’t popular in the US but found some use in PAL applications. I
may someday tell the story of<SPAN style="mso-spacerun: yes">
</SPAN>“removing” Pilot Tone from TR600’s in Australia </SPAN></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"> </P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">C) The TR60/61, TR70 The
silicon era 2n4400 series brought in </SPAN>HI<SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">-band & Air Bearings
& the Venturi for head wheel guide Vacuum. Most Stations supplied
Hi pressure Air from a central system.</SPAN> The drop out Comp, and decent
TBC </P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial"> <o:p></o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">My memory also triggered a TIP for
those PPL who restore RCA TR 70C & TCR-100 Machines.
The Turnaround Tape Guide (below the supply TT on the 70C and after
the Capstan on the TCR100) has one of those stupid factory-induced flaws.
The assembly required that the threads of the screw attaching the
Vertical post (shaft) to the Boss have a drop of Gyptol (thread Lock)
<o:p></o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">The brilliant factory Gorilla (same
guy for Years) assembling those parts filled the Boss with Gyptol,
this resulted in the Post been effectively mounted on a flexible base
(rubber like). The Fix is to remove the shaft & clean the mounting area
of all Gyptol, apply lock tight to threads and reassemble. The tape path
will then be absolutely perfect. This problem was finally found during
Customer checkout of the final 7 TCR100's built & sold, it was the end
of Shimming Capstans and delaying Cue detection.</SPAN></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"> </P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">I would hazard a guess that 99
% of EOT tape damage & Operational miscue faults (TRC100) were due
to this fault.</SPAN> </P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><FONT face=Arial
size=2></FONT> </P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><FONT face=Arial
size=2></FONT> </P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><FONT face=Arial size=2>Phillip
G. Shaw</FONT></P>
<P class=MsoNormal
style="MARGIN: 0in 0in 0pt"> <o:p></o:p></P></DIV></BODY></HTML>