[QuadList] Restoring an RCA TR-600

Steve Greene steve.greene at nara.gov
Wed May 27 16:34:29 CDT 2009


John,
This jogs my memory.  You will need a sync generator that can supply burst and subcarrier before the machine will fully lock.  Color bars will serve in place of black burst in a pinch.

Steve Greene
Audiovisual Archivist
Nixon Presidential Library and Museum
(301) 837-1772
>>> park at videopark.com 05/26/09 1:23 PM >>>
Congratulations on your acquisition, John. While I know absolutely  
nothing about the RCA quads, I can share some experiences with  
restoring Ampex quads.

As said before, check the power supplies. I have replaced most of my  
large caps. After repair, run the power supplies on a test bench under  
load for a few hours to see if it really is good.

I remove every circuit board (called "etched boards" in Ampex lingo)  
and inspect for obvious damage and clean off any dirt and grime. I  
have seen caps that have exploded and resistors that have burned up. I  
measure every capacitor with an ESR meter and replace ones that are  
suspect. I have also been known the shotgun the board and replace all  
the electrolytics. The smaller mylar and tantalums seem to hold up.

I then clean the contacts, first with a special gold eraser (similar  
to an ink eraser) and then wipe clean with an alcohol swab. Then, coat  
with DeoxIT Red, wipe off and then coat with DeoxIT Gold and wipe off.  
I use the 100% solution. Let it remain on the surface for some time  
and wipe off. Could leave it on overnight on really bad corrosion.

DeoxIT® - Contact Cleaner & Rejuvenator - Brings Old Systems Back to  
Life!
DeoxIT® GOLD (formerly ProGold) - Contact Conditioner & Protector -  
Maintains New System Performance!

The biggest problems in equipment I have seen are power supply  
problems and connector problems.

Following the schematics, I look at the circuit  and start at the  
beginning and follow it until I see a problem. Ampex has some  
excellent manuals that show exactly what the waveforms should look  
like at every step in the circuit.

The 1200 I am working on now has had problems at every step. Nothing  
was working. Now, I have good air and full video and am starting to  
work on the mechanics. My machines were very dirty so a good cleaning  
of all parts is recommended.

Another good tip is to find someone with knowledge of the VTR that you  
can bounce ideas off. Don Norwood has been very helpful to me. He has  
a wealth of knowledge on the 1200s.

You said you were feeding sync from a generator. The Ampex machines  
require separate sync, burst and other drives. Make sure your VTR is  
getting all the drives it needs.

I've got 7700 hours on my oldest machine. It's almost broken in!

Good luck!

Best,
Park

C. Park Seward
Visit us: http://www.videopark.com



On May 26, 2009, at 6:57 AM, John Walko wrote:

> 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)






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