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LC III PRAM battery solutions
Posted by: Challenger 1983 on 2020-10-27 05:06:27
I recently took a gamble on a non-working LC III logic board on ebay, it turns out a quick isopropyl wash got it to chime and boot, only problem Is that pesky PRAM battery as it controls video on these models and It makes me worried leaving one in the machine, has anyone come up with a solution to this issue?

Posted by: MrFahrenheit on 2020-10-27 05:49:04
I buy a 4 pack on amazon for $18 CAD free shipping. The ones I buy are Xeno brand. 
 

If you’re interested in having it recapped I can provide that service for you. 

Posted by: Challenger 1983 on 2020-10-27 09:12:41
I buy a 4 pack on amazon for $18 CAD free shipping. The ones I buy are Xeno brand. 
 

If you’re interested in having it recapped I can provide that service for you. 
Ah okay, I’ll get some on amazon, I’m probably going to attempt this Recap myself but If not I’ll definitely send it your way🙂

Posted by: bibilit on 2020-10-27 09:24:47
None of mines have a battery, only required for very few models.

Posted by: Challenger 1983 on 2020-10-27 10:12:17
None of mines have a battery, only required for very few models.
All of my machines (very few left due to an accident a few years back) have their PRAM batteries removed, unfortunately this machine needs it in order to display an image 

🙁

Posted by: erichelgeson on 2020-10-27 11:06:13
unfortunately this machine needs it in order to display an image
My LCIII has never(removed it before I recapped it) had a pram battery in and works fine - maybe something else going on here?

Agree I have a few sets of Xeno and they work fine for the machines I do have a battery in.

Posted by: Challenger 1983 on 2020-10-27 13:02:50
My LCIII has never(removed it before I recapped it) had a pram battery in and works fine - maybe something else going on here?

Agree I have a few sets of Xeno and they work fine for the machines I do have a battery in.
I was always under the impression that the LC III needs a battery to work, mine will not display video without one but as soon as I install a battery it works just fine

Posted by: bibilit on 2020-10-27 15:08:11
The only LC needing a battery is the 475, not the III. 

Logic board swap ?

Posted by: Challenger 1983 on 2020-10-27 16:42:28
The only LC needing a battery is the 475, not the III. 

Logic board swap ?
It says LC III on the board 

Posted by: MrFahrenheit on 2020-10-27 17:25:21
I was always under the impression that the LC III needs a battery to work, mine will not display video without one but as soon as I install a battery it works just fine


LC series machines all need working batteries to work properly.  This is how I buy cheap "non-working" LC machines on eBay.  They work, just the battery is dead.

Posted by: Challenger 1983 on 2020-10-27 19:27:09
LC series machines all need working batteries to work properly.  This is how I buy cheap "non-working" LC machines on eBay.  They work, just the battery is dead.
I figured, I’ll buy a battery on amazon, I saw I can get the tadiran original battery so I’ll buy one of those

Posted by: bibilit on 2020-10-28 00:39:35
LC series machines all need working batteries to work properly.  This is how I buy cheap "non-working" LC machines on eBay.  They work, just the battery is dead.


I have the whole set, none of them had a battery, and except the 475, all working fine with no issue.

Posted by: cheesestraws on 2020-10-28 06:05:22
LC series machines all need working batteries to work properly


That seems odd, because I don't run any of mine with batteries in.  I don't have any 040 LCs, but the I/II/III are fine...

Posted by: Daniël on 2020-10-28 07:10:53
LC series machines all need working batteries to work properly.  This is how I buy cheap "non-working" LC machines on eBay.  They work, just the battery is dead.
My "regular" LCs do not need batteries at all to function, this seems doubtful.

Posted by: MrFahrenheit on 2020-10-28 08:28:38
My "regular" LCs do not need batteries at all to function, this seems doubtful.
While I understand your experiences how do you explain mine?  I have nearly 30 LC class machines from LC-LC475. 

Posted by: Challenger 1983 on 2020-10-28 09:30:29
While I understand your experiences how do you explain mine?  I have nearly 30 LC class machines from LC-LC475. 
Is it p

That seems odd, because I don't run any of mine with batteries in.  I don't have any 040 LCs, but the I/II/III are fine...


Is it possible that we all have different rev boards? 

Posted by: MrFahrenheit on 2020-10-28 13:52:23
Is it p

Is it possible that we all have different rev boards? 
 
That’s certainly a possibility. Many of my boards have the red push button reset for PRAM on the board. LC/LC2/LC3 and LC475. 

Posted by: Challenger 1983 on 2020-10-28 14:31:13
 
That’s certainly a possibility. Many of my boards have the red push button reset for PRAM on the board. LC/LC2/LC3 and LC475. 
Mine has no Reset button but there are solder pads for one

Posted by: Brett B. on 2020-10-29 07:50:05
I have had dozens of pizza box LCs of every variant over the years - the ONLY one that has a PRAM battery quirk is the 475.  Turn it on, wait for the chime, flip it off and back on again quickly and you're good to go.  NONE have done anything past simply not holding the date/time/etc.  None.

I would suspect a flaky power supply or capacitor electrolyte damage on ANY LC/II/III/III+ that doesn't go straight to video when powered on.

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