[QuadList] Restoring an RCA TR-600

Tue May 26 10:47:54 CDT 2009

Gary, Steve:

Thanks for the input.this is great information.

We have three boxes of manuals.I didn't look at them too closely because I
thought they were operators manuals.  Turns out we have a three ring binder
as well as a spiral binder.  I believe these are labeled maintenance
adjustments (the spiral is about 1" thick.the 3-ring is about 2"
think.appears at a quick glance to have lots of good information).  I also
have what appears to be all (or certainly a lot) of the technical bulletins.

Steve.regarding the TBC.we haven't identified one yet to use with this
machine.at this point we want to get it making pictures.  Then we'll
evaluate TBCs.  Is there anything specific we should look for in a TBC so
that it will work with this machine?

Thanks again.

John Walko

From: quadlist-bounces at quadvideotapegroup.com
[mailto:quadlist-bounces at quadvideotapegroup.com] On Behalf Of Gary Adams
Sent: Tuesday, May 26, 2009 11:10 AM
To: 'Quad List'
Subject: Re: [QuadList] Restoring an RCA TR-600

I would concur with this.  You pretty much have to do the video and servo
alignment as it will most likely not be close.  A simple hint. If you pull
the Pixlock board, you can still run the machine with tape through the head
without it spinning.  At least you won't damage the head or tape doing this
and it will verify the capstan servo and such.  I don't like to risk ruining
a head or tape the first try.  Make sure the tension arm dampers are set and
work according to spec or they will fight you.

Gary

From: quadlist-bounces at quadvideotapegroup.com
[mailto:quadlist-bounces at quadvideotapegroup.com] On Behalf Of Steve Greene
Sent: Tuesday, May 26, 2009 10:51 AM
To: quadlist at quadvideotapegroup.com
Subject: Re: [QuadList] Restoring an RCA TR-600

Congratulations on your new acquisition.  

I assume you have a full raft of the available documentation.  I
particularly recommend the spiral bound manual they issued to engineers
attending the RCA technical seminars.  

I ran a number of these machines so I have some recommendations.  First,
replace the main power capacitor (the oil can sized thing housed in its own
shield hanging off the power supply).  This cap is at least thirty years old
now and you can assume it is half dried out.  Be careful, it can hold enough
current to toss you across the room or kill you.  On our machines, this
cured much unexplained flakiness that plagued these machines and gave them a
rep for unreliability.  Before I replaced it, the compressed air ran though
the card cage and voltage regulator circuit during cleanup was enough to
light the machine up like a Christmas tree.

The downside will be that you will pretty much have to run through all the
basic setups afterward.  Second, replace all the nylon vacuum fittings with
brass.  The nylon parts will fail.  I've seen unused spares cracked in the
factory boxes.  Third, clean and replace all the air and vacuum filters.
Fourth, clean the linkages behind the headwheel panel.  Tape flakes and dust
will foul them and slow the reaction time of the vacuum guide.  Hopefully
you have the jig that allows you to adjust those linkages.  Fifth, clean the
card edge fingers for each card (tape flakes and dust get everywhere in
these machines).  Sixth, look for spares for the headwheel power amp
transistors and the darlington transistors used in the proc amp section and
elsewhere.

You are right in thinking that your vacuum should be at 35 inches.  I would
run the machine at 70psi.  Hopefully the replacement of the nylon fittings
may solve your problems with both.  The guide on the head is opened and
closed manually for thread-up.  If you still have lockup problems after
these drastic measures, then yes, look for stuck relays or board-level
issues.

On our machines, the native TBC never quite tamed the jitter on the leading
edge of sync that many of our off-air tapes contained.  You may need to look
for alternative TBCs.  

Hope this is helpful.  Feel free to call if you have further questions.

Steve

Steve Greene
Audiovisual Archivist
Nixon Presidential Library and Museum
(301) 837-1772

>>> jwalko at scenesavers.com 5/26/2009 9:57:30 AM >>>

Hello Group:

Well.a bit of exciting news.at least for me.  We've acquired three TR-600
Quad machines.  Unfortunately, one had to be reduced to parts to move it,
but at least we have the parts, including motors, control boards, spare
heads, etc.

I need some help and advice from the group.

We've identified the one machine that we feel has the best chance of being
operational again.  This past weekend, we ran power and air and powered up
the machine.  We check the test points in the power supply and everything
appears to meet proper voltage parameters and the voltage appears stable.
There are no air or vacuum leaks that we can tell.so this appears good.
However, we are not getting stable video or any audio (see below).  I would
appreciate some advice.

1.       We are running the air at about 55 PSI (adjusted at the machine.120
from the air compressor).  Vacuum is at 20 inches.  According to the manual,
this should be a little higher, but 20 is the highest we can get it to peak.
Adjusting the air pressure didn't affect the vacuum.  Vacuum being at 20
does not appear to be causing any problems, but I am wondering if there is
something we are not seeing.  

2.       When we put the machine into thread mode, the capstan releases and
the tension arms move up and out of the way.  The arm on the head drops to
allow threading.  When we hit stop to take it out of thread mode, the arm on
the head does not automatically move back to position the tape against the
head.should this be automatic or do you have to manually close this arm?

3.       When the machine is threaded and the tape properly seated, the
vacuum goes off the dial.  I assume this is normal (sort of like putting
your hand over the suction end of a vacuum cleaner).  Is this correct?

4.       We get a video signal, but it is all broken apart.  We were getting
a "lock" error, but are able to correct this by adjusting the capstan speed.
But the video is the wrong color (appears as if Chroma is all off).  Any
thoughts as to what to look for (perhaps a board in the system).

5.       We get no audio unless we step on the foot switch.  If we manually
turn the reels while depressing the foot switch, we get audio (both in
forward and reverse), however as soon as the foot switch is released, audio
immediately goes away.  We thought this might be related to the capstan, but
the audio goes away even before the capstan is fully engaged.  Perhaps a
relay is sticking or is bad.  Any ideas?

A couple of other items.

1.       We were feeding synch from a synch generator

2.       We re-seated all the boards (with the machine powered off)

3.       We tried two different heads.both heads appear to have slight
burnishing, but are not in bad shape.  Neither made a difference.

4.       One of our Engineers used to operate one of these machines years
ago for a TV station he worked for.so he is somewhat familiar with it.but it
was a long time ago.

5.       We have a second machine that is complete.but the air fittings are
cracked (they appear to be nylon with push in connectors).  We also get no
vacuum on that machine, so it would need some work before being operational.
Not sure why no vacuum.it could be related to the air leak or the vacuum
pump.

6.       We have at least one spare of everything.and are willing to try
some things to get this system operational.

7.       Both machines were taken out of service at about the same time.and
haven't been operated in years.  One machine (the one we are working on) has
3200 hours on the machine.the other has about 5000 hours (the one that has
the air leak).

Any TR-600 experts interested in coming here to help?  We could discuss
reimbursement for your time and travel.

Please call me at 800-978-3445 or email me any thoughts that might be
helpful (I.e. things to check/test/look for, etc.).

Thanks;

John Walko

Media Archive Manager

Scene Savers

www.scenesavers.com

800-978-3445

513-708-1474 (cell)

859-291-5100 (office)

John Walko

Media Archive Manager

Scene Savers

www.scenesavers.com

800-978-3445

513-708-1474 (cell)

859-291-5100 (office)

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