Big ursa magenta screen of death

Bob Hart · January 27th, 2020, 12:34 AM

A postscript to the broken camera saga.

I managed to find on eBay, another broken Ursa, an EF-Mount. This camera's etiology was incremental demise via power management. There was a strong chance the camera head was good and it turned out to be so.

The filter placement and collimation of the EF-Mount turret to the sensor was different so I ended up moving the entire sensor and PCBs across to the PL-Mount turret. I bench tested everything and it seemed fine.

In removing the supercapacitor from the motherboard, a solder pad came off the PCB. The layers on these boards are exceptionally thin. However it seems to function quite happily without it.

It seems maybe that the supercapacitor serves as a memory battery. I did not observe previously but it seems that when the camera is powered down, any time-date settings revert to the camera's birthday and playback clip order shifts in accordance with just when individual clips were started during power-on periods.

The SI2K also does this when the memory batteries go flat. Whether there is a conflict between files if one initiates during the same time period written to another file I have yet to discover. I may have to reset times and dates during each power cycle before rolling.

Andrew Smith · January 27th, 2020, 01:39 AM

Interesting to hear!

So, an otherwise usable camera once again?

Andrew

Bob Hart · January 28th, 2020, 12:13 PM

It is usable again for now. Even its own power management glitch seems to have gone away.

It went through a period where it would not power-on from a battery unless it was "jump-started" from the 4pin XLR power input first, then for the remainder of the day it would run fine off the battery.

I wonder if the sensor/sensor PCBs in the failed turret may have been drawing too much power on its way to failure.

Whichever, I am going to accept what comes gratefully, hopefully for some time yet.

Bob Hart · August 11th, 2020, 10:06 PM

The patched up "big" URSA still lives.

You get to see and do some fun things with a camera sometimes. This was filming a smoke generator test for a friend and co-writer of a film script..

He has all the necessary permissions and skillset for this display.

January 27th, 2020, 12:34 AM	#16
Bob Hart Inner Circle Join Date: Dec 2003 Location: PERTH. W.A. AUSTRALIA. Posts: 4,476	Re: Big ursa magenta screen of death A postscript to the broken camera saga. I managed to find on eBay, another broken Ursa, an EF-Mount. This camera's etiology was incremental demise via power management. There was a strong chance the camera head was good and it turned out to be so. The filter placement and collimation of the EF-Mount turret to the sensor was different so I ended up moving the entire sensor and PCBs across to the PL-Mount turret. I bench tested everything and it seemed fine. In removing the supercapacitor from the motherboard, a solder pad came off the PCB. The layers on these boards are exceptionally thin. However it seems to function quite happily without it. It seems maybe that the supercapacitor serves as a memory battery. I did not observe previously but it seems that when the camera is powered down, any time-date settings revert to the camera's birthday and playback clip order shifts in accordance with just when individual clips were started during power-on periods. The SI2K also does this when the memory batteries go flat. Whether there is a conflict between files if one initiates during the same time period written to another file I have yet to discover. I may have to reset times and dates during each power cycle before rolling.

January 27th, 2020, 01:39 AM	#17
Andrew Smith Equal Opportunity Offender Join Date: Feb 2009 Location: Brisbane, Australia Posts: 3,061	Re: Big ursa magenta screen of death Interesting to hear! So, an otherwise usable camera once again? Andrew

January 28th, 2020, 12:13 PM	#18
Bob Hart Inner Circle Join Date: Dec 2003 Location: PERTH. W.A. AUSTRALIA. Posts: 4,476	Re: Big ursa magenta screen of death It is usable again for now. Even its own power management glitch seems to have gone away. It went through a period where it would not power-on from a battery unless it was "jump-started" from the 4pin XLR power input first, then for the remainder of the day it would run fine off the battery. I wonder if the sensor/sensor PCBs in the failed turret may have been drawing too much power on its way to failure. Whichever, I am going to accept what comes gratefully, hopefully for some time yet.

August 11th, 2020, 10:06 PM	#19
Bob Hart Inner Circle Join Date: Dec 2003 Location: PERTH. W.A. AUSTRALIA. Posts: 4,476	Re: Big ursa magenta screen of death The patched up "big" URSA still lives. You get to see and do some fun things with a camera sometimes. This was filming a smoke generator test for a friend and co-writer of a film script.. He has all the necessary permissions and skillset for this display. FOURNIER EXTRACT 6 40 7 18 - YouTube Last edited by Bob Hart; August 11th, 2020 at 10:09 PM. Reason: error