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Author Topic: 5050 playback problem  (Read 4383 times)

Offline jimkjr

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5050 playback problem
« on: January 16, 2012, 07:12:52 PM »
I just recently acquired another 5050 BII 2,and set it up to play a 4trk tape.It statrs playing fine for the first 2 1/2 minutes,then goes haywire,at abot 2 min. 50 sec.,like it is mistracking or trying to play additional channels. I can FF to different parts of the tape,and it remains the same.I can rewind it back to 20sec. and start it playing again,and it is fine until it hits that same 2+ min.Also while the tape is playing,(first 2 min.)I try to change from 2 to 4trk and back,and nothing happens to the sound.I would assume I should hear some kind of difference!
Anyone have any suggestions as to this cause.

Thanks
Jim
Jim

Offline ironbut

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Re: 5050 playback problem
« Reply #1 on: January 16, 2012, 08:38:31 PM »
Hey Jim,

Sounds like an issue with the head switch.
From your description, it would appear that it's not switching from the 1/2 track head to the 1/4 track head.
It's a common problem with these 4 head machines and most times all it takes is cleaning of that switch. I have also seen it where (for whatever reason) folks have disabled the it by cutting the wires but that's kinda rare.
I'd first try "working" the switch back and forth a 10 times or so in hopes of scraping a clean spot on the switch contacts (sometimes these machines were only used for 1/2 track playback so the 1/4 track contact will have had 30+ years to tarnish and pick up contaminants from the air).
If you listen while doing this, you should hear an audible difference in level since the output of the two heads is slightly different.

If "working" the switch doesn't work, you can try squirting it with a little contact cleaner and at the most, you may have to remove it, take it apart and clean the contacts directly.
steve koto
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Offline jimkjr

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Re: 5050 playback problem
« Reply #2 on: January 16, 2012, 10:30:07 PM »
Steve
Thank you for the quick reply! It was also my feeling that indeed it was a switch problem. But why the playing OK for the first few minutes,and then the problem with the mistracking?

I do believe this 5050 was used solely for 2 trk,as I believe it may be the machine that was used on the road to tape the Grateful Dead.That is something that is now being researched.

Thanks again
Jim
Jim

Offline docb

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Re: 5050 playback problem
« Reply #3 on: January 16, 2012, 11:06:16 PM »
There is no signal on the reverse direction (side 2) tracks for 2 minutes and 50 seconds, because that "side" ends 2 minutes and 50 seconds before the first side.
Dan "Doc B." Schmalle
President for Life, Bottlehead Corp.
Managing Director - retired, The Tape Project

Offline ironbut

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Re: 5050 playback problem
« Reply #4 on: January 17, 2012, 12:33:29 AM »
I do believe this 5050 was used solely for 2 trk,as I believe it may be the machine that was used on the road to tape the Grateful Dead.That is something that is now being researched.

Not that I doubt that the Dead used a number of reel to reels, here's a link to some info regarding the machine that they used for the European Tour in 72 and the album aptly name "Europe 72" (I still have images of the album cover etched on the insides of my eyelids!).

http://www.archive.org/post/345457/recordist-credits-for-europe-72-alembic-sound

BTW The guys on the Ampex list called several of the technical items in the text into question. Please take it all with a grain of salt and simply appreciate the inspiration and hard work it takes to put something like this machine together,
« Last Edit: January 17, 2012, 12:42:57 AM by ironbut »
steve koto
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Offline jimkjr

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Re: 5050 playback problem
« Reply #5 on: January 17, 2012, 07:00:07 PM »
Steve and DocB
Thank you for your help.Yes,it was the switch,I had to spray it,but it is working like a charm now!

Jim
Jim