Expression 3 Losing Data Cont'd

Replying in same thread hoping some one sees it if not I'll post a new thread.

The new caps were working well until we had to completely disconnect the board nd wrap it up as a hurricane precaution. After resurrecting it we found that turning off overnight lost all the memory (subs, cues etc). I left it on for a few days to really stuff those caps but to no avail, So questions is are the new caps bad now or could there be another culprit. I'm tryin to work out if it worth me getting the battery upgrade kit and overcoming these super cap problems. Be a pity to go to all that work and find out thee was another culprit. Anyone know the price of the battery upgrade for the EXP3?

Hi Robert452,

I know you posted already elsewhere, but I wanted to ask a question here to try to pin down where the problem may be. How long was the console shut off while it was in hurricane protection mode?
I ask because the supercaps maintain charge for 4-6 days, typically. After that, the caps will lose enough charge to cause the SRAM to lose show memory If the console was off for a couple weeks, then show memory will normally be lost. New supercaps might last a little more than a week but the charge duration of the supercaps will drop over time as the caps age. After 20 years, the supercaps may only last a few hours or a day at most, if at all.

The new supercaps should still be OK. If the console was powered off for only a day or two, then I'd suspect the SRAM or the voltage supervisor chip (if your CPU board has it), as they're the only things remaining that use the supercaps. There are 8 SRAM chips, located above the DRAM slots. Unfortunately, those SRAM chips are no longer available should one or more be bad. ETC does have a small stock for repairs, but the console would need to be sent in to get those replaced as we don't send those parts out.

If you'd like to know if your new supercaps are actually bad, measure the voltage on pin 32 of one of the SRAM chips (probably U57 to U64 on your CPU board, directly across from pin 1, which would be marked with a recessed dot or a laser-etched dot on the notched side of the chip). When the console is on, it should read about 4.2-4.7V. With the console powered off, that number will drop slowly over time. If it drops by 1.0V or more after a day of being powered off, then the supercaps (or the voltage supervisor chip) are likely bad. Once the SRAM voltage drops to 2.0V or below, show memory will be erased.

I hope this helps a little.

Hi Robert452,

I know you posted already elsewhere, but I wanted to ask a question here to try to pin down where the problem may be. How long was the console shut off while it was in hurricane protection mode?
I ask because the supercaps maintain charge for 4-6 days, typically. After that, the caps will lose enough charge to cause the SRAM to lose show memory If the console was off for a couple weeks, then show memory will normally be lost. New supercaps might last a little more than a week but the charge duration of the supercaps will drop over time as the caps age. After 20 years, the supercaps may only last a few hours or a day at most, if at all.

The new supercaps should still be OK. If the console was powered off for only a day or two, then I'd suspect the SRAM or the voltage supervisor chip (if your CPU board has it), as they're the only things remaining that use the supercaps. There are 8 SRAM chips, located above the DRAM slots. Unfortunately, those SRAM chips are no longer available should one or more be bad. ETC does have a small stock for repairs, but the console would need to be sent in to get those replaced as we don't send those parts out.

If you'd like to know if your new supercaps are actually bad, measure the voltage on pin 32 of one of the SRAM chips (probably U57 to U64 on your CPU board, directly across from pin 1, which would be marked with a recessed dot or a laser-etched dot on the notched side of the chip). When the console is on, it should read about 4.2-4.7V. With the console powered off, that number will drop slowly over time. If it drops by 1.0V or more after a day of being powered off, then the supercaps (or the voltage supervisor chip) are likely bad. Once the SRAM voltage drops to 2.0V or below, show memory will be erased.

I hope this helps a little.

Something to look at. The board was entirely disconnected for over two weeks. I suspect that although the console is OFF the PSU normally supplies a trickle charge to the suprcaps. We often had the board down for a month or more (but still plugged into a live socket) over a period of 18 years. I was hoping that plugging in and leaving the board on might charge up the new supercaps. No Joy.  I will try those voltages and perhaps put in another set of the supercaps (everything was fine last time unitl the enforced disconnect).

We really like the EXP3 in our Pavilion theater because it is not all that different from our Element 2 in the main theater so I am putting out feels to see if we can get hold of anther CPU board, perhaaps from a mothballed unit soemone has. But - again thank you. I was surprised to get a reply here as - great as they were - they are fast fading.