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Topic: leds for Strong Phase Controls

Rick Long
Jedi Master Film Handler

Posts: 759
From: Toronto, Ontario, Canada
Registered: Nov 1999

posted 08-09-2002 12:40 AM

We have learned from experience, over the last few years, that leds used as light sources for level-sensitive equipment, such as digital and analog soundheads, do fade over time and require occassional re-adjustment.

This problem, however is not limited just to soundheads, but also to such equipment, apparently as Strong phase controls. These units, which when new pay-out film with no problem, suffer from considerable drag as they get older.

Our experience has been that fooling around with the on-board pot to bring up the led level provides only a temporary cure, and soon a replacement phase control is needed.

To me, it seems a shame to have to replace the entire phase control assembly if only the led is at fault.

To this end, will Strong please make available a replacement led for this unit?

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Pete Naples
Phenomenal Film Handler

Posts: 1565
From: Dunfermline, Scotland
Registered: Feb 2001

posted 08-09-2002 07:22 AM

Surely (although I've never had any trouble with these as yet), the LED is an off the shelf device, available from any electronics supplier?

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Rick Sanjurjo
Film Handler

Posts: 26
From: Omaha, NE, USA
Registered: Jul 2002

posted 08-09-2002 07:47 AM

Rick,

The only LED I have a had to replace is on the DMC, the replacement part number for that is 2468249. If you are having troulbe with the phase control let me know and I will get you a part number for that LED.

Rick

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Joe Redifer
You need a beating today

Posts: 12859
From: Denver, Colorado
Registered: May 99

posted 08-09-2002 09:41 AM

Please post that part number here in the thread for other users who may have some need for it down the road.

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System Notices
Forum Watchdog / Soup Nazi

Posts: 215

Registered: Apr 2004

posted 09-09-2009 03:50 PM

It has been 2588 days since the last post.

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Dominic Espinosa
Phenomenal Film Handler

Posts: 1172
From: Boulder Creek, CA.
Registered: Jan 2004

posted 09-09-2009 03:50 PM

Anybody have the part number forf these?
I've got a bunch laying around and would love to repair in-house...

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Joe Redifer
You need a beating today

Posts: 12859
From: Denver, Colorado
Registered: May 99

posted 09-09-2009 06:01 PM

I found a bunch of 6-year-old phase control boxes that had been removed from our brains because the technician couldn't get them to work properly. They replaced them with microswitches. I do not like microswitches, so I put the phase control boxes back into service. No problems! What matters most is the positioning of the box itself vs the actual LED. Don't play with the LED much if you don't have to. Sure, they won't last forever, but they can last at least 7-8 years without any issues easily.

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Gordon McLeod
Film God

Posts: 9532
From: Toronto Ontario Canada
Registered: Jun 99

posted 09-09-2009 07:02 PM

i still prefer the micro switch

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John Walsh
Film God

Posts: 2490
From: Connecticut, USA, Earth, Milky Way
Registered: Oct 1999

posted 09-09-2009 08:13 PM

Don't be surprised, Joe, if they crap out fairly soon. I'm with Gordon; put the microswitches in. It takes a little time, but they can be set to pay out without the film actually running against the 'guard' rollers around the head.

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Mark Gulbrandsen
Resident Trollmaster

Posts: 16657
From: Music City
Registered: Jun 99

posted 09-09-2009 08:26 PM

Ditto, Using the right Microswitch I can get a microswitch equipped platter to run almost as smooth as a phase control platter can. I also have a mod that no one here has thought of that will get you 5 to 7 years out of your microswitches!!

By the way Joe, If those are the platters fomr SLC I AM the one that took those phase controls off...

Mark

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Monte L Fullmer
Film God

Posts: 8367
From: Nampa, Idaho, USA
Registered: Nov 2004

posted 09-09-2009 09:32 PM

quote:
I also have a mod that no one here has thought of that will get you 5 to 7 years out of your microswitches!!

Is that the "snubber" trick - using a cap and a resistor?

And if so, what were the values of each component so I can do the snubber trick on our switched brains..

thx -Monte

p.s. (true Joe, I also love phase controls over microswitch - for I have one platter that I do use phase controls on and never had a hitch with that platter concerning payout problems..and these controls are over 20 yrs old. ... )

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Joe Redifer
You need a beating today

Posts: 12859
From: Denver, Colorado
Registered: May 99

posted 09-09-2009 10:24 PM

Mark, the platters I refer to are not ones from Salt Lake City. Plus, the old phase controls I have put back in have been running perfectly for nearly a year now. They don't even wobble. Most are completely still as they pay out. The microswitches stuck all the time. So much fewer problems with the phase control. Then again NO problems is always fewer than any problem. [Smile]

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Mark Gulbrandsen
Resident Trollmaster

Posts: 16657
From: Music City
Registered: Jun 99

posted 09-09-2009 10:27 PM

quote: Monte L Fullmer
Is that the "snubber" trick - using a cap and a resistor?

Nope. That actually does very little to prolong the life of the switch.

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Jeremy Weigel
Phenomenal Film Handler

Posts: 1062
From: Edmond, OK, USA
Registered: Mar 2007

posted 09-10-2009 01:17 AM

Converted all our carbon switched brains to micro switches in 1995 and haven't had one fail yet.

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Mark Gulbrandsen
Resident Trollmaster

Posts: 16657
From: Music City
Registered: Jun 99

posted 09-10-2009 04:20 PM

Jeremy,

The switches made back then were alot higher quality and since the advent of lead free contacts they don't last very long. Also, I bet you are still running switches that are tensioned for acetate film.... not for estar film. There IS a big difference there.

Mark

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