Re: NiCd battery replacement in vintage computers

On 02/08/2016 06:55 AM, Maciej W. Rozycki wrote: As a matter of interest I've checked the MC146818 datasheet and it claims a 50µA current draw in the usual configuration with a 32768Hz oscillator. Yup. And things have only gotten better with time. I suspect that you could power the '818

Re: NiCd battery replacement in vintage computers

On Sat, 6 Feb 2016, Chuck Guzis wrote: > You're talking about RTC and perhaps a bit of static RAM maintenance. If this > RTC unit is like most of the same era, the operating voltage range is quite > wide (probably about 2-7V) and sub-1ma current draw. Chargers for this type of > application are

Re: NiCd battery replacement in vintage computers

, February 8, 2016 6:55 AM To: General Discussion: On-Topic and Off-Topic Posts Subject: Re: NiCd battery replacement in vintage computers On Sat, 6 Feb 2016, Chuck Guzis wrote: > You're talking about RTC and perhaps a bit of static RAM maintenance. If this > RTC unit is like mo

Re: NiCd battery replacement in vintage computers

> On Feb 8, 2016, at 07:08 , dwight wrote: > > Make sure to neutralize the leaked alkaline stuff from the cells. > Just a simple cleaning isn't enough. I use white vinegar. I physically removed the affected area down to bare copper and fiberglass:

Re: NiCd battery replacement in vintage computers

I found a reference which states that the NVRAM is used to hold SCSI controller parameters. I decided to mount a CR123A holder inside the case on one of the slot filler panels. I had some through-hole PCB mount CR123A holders left over from a previous project. I machined a mounting base for

Re: NiCd battery replacement in vintage computers

> On Feb 6, 2016, at 4:21 PM, Mark J. Blair wrote: > > Today I discovered that I hadn't replaced the NiCd battery in time in my > Amiga 3000. Pictures: > ... > While I begin to figure out how I'd like to perform this repair, I'm curious > about what others have decided to do in

NiCd battery replacement in vintage computers

Today I discovered that I hadn't replaced the NiCd battery in time in my Amiga 3000. Pictures: https://twitter.com/nf6x/status/696042894939979776 https://twitter.com/nf6x/status/696050264306921472 https://twitter.com/nf6x/status/696065578977472512 It's a fairly typical 3.6V 60mAH 3-cell NiCd

Re: NiCd battery replacement in vintage computers

On 2016-Feb-06, at 1:21 PM, Mark J. Blair wrote: > Today I discovered that I hadn't replaced the NiCd battery in time in my > Amiga 3000. Pictures: > > https://twitter.com/nf6x/status/696042894939979776 > https://twitter.com/nf6x/status/696050264306921472 >

Re: NiCd battery replacement in vintage computers

On 02/06/2016 1:29 PM, Paul Koning wrote: On Feb 6, 2016, at 4:21 PM, Mark J. Blair wrote: Today I discovered that I hadn't replaced the NiCd battery in time in my Amiga 3000. Pictures: ... While I begin to figure out how I'd like to perform this repair, I'm curious about what

Re: NiCd battery replacement in vintage computers

On 02/06/2016 1:29 PM, Paul Koning wrote: On Feb 6, 2016, at 4:21 PM, Mark J. Blair wrote: Today I discovered that I hadn't replaced the NiCd battery in time in my Amiga 3000. Pictures: ... While I begin to figure out how I'd like to perform this repair, I'm curious about what

Re: NiCd battery replacement in vintage computers

In this Amiga, the battery is just for a real time clock. I don't think the A3000 saves any parameters in nonvolatile memory.

Re: NiCd battery replacement in vintage computers

On Sat, 6 Feb 2016, Lyndon Nerenberg wrote: > > I see all the talk about NiCd cells--does no one use NiMH nowadays? > > Why go with the toxics? > > Voltage? Recharging circuits? Current sinking capacity. It's not > always a 1:1 mapping. Sure, but does it really matter in a typical

Re: NiCd battery replacement in vintage computers

On 02/06/2016 05:05 PM, Lyndon Nerenberg wrote: Voltage? Recharging circuits? Current sinking capacity. It's not always a 1:1 mapping. You're talking about RTC and perhaps a bit of static RAM maintenance. If this RTC unit is like most of the same era, the operating voltage range is

Re: NiCd battery replacement in vintage computers

> On Feb 6, 2016, at 16:59, Chris Pye wrote: > This is what I normally do, preferably mounted away from the board. Generally > you can get away with simply using a diode to prevent the circuit trying to > charge the battery. I think that a blocking diode added in the

Re: NiCd battery replacement in vintage computers

> On 7 Feb 2016, at 7:21 am, Mark J. Blair wrote: > > * Reconfigure the circuit to use a non-rechargeable lithium coin cell in a > holder instead. I don't think I've seen one of those leak before. This is what I normally do, preferably mounted away from the board. Generally

Re: NiCd battery replacement in vintage computers

I see all the talk about NiCd cells--does no one use NiMH nowadays? Why go with the toxics? --Chuck

Re: NiCd battery replacement in vintage computers

> On Feb 6, 2016, at 5:03 PM, Chuck Guzis wrote: > > I see all the talk about NiCd cells--does no one use NiMH nowadays? Why go > with the toxics? Voltage? Recharging circuits? Current sinking capacity. It's not always a 1:1 mapping.

Re: NiCd battery replacement in vintage computers

> On Feb 6, 2016, at 5:31 PM, Maciej W. Rozycki wrote: > >> Voltage? Recharging circuits? Current sinking capacity. It's not >> always a 1:1 mapping. > > Sure, but does it really matter in a typical battery-backed-up RAM or RTC > application seen in computers? I

Re: NiCd battery replacement in vintage computers

> On Feb 6, 2016, at 19:18, Chuck Guzis wrote: > > If you're not interested in a "authentic" look, a plain old lithium primary > coin cell or two, with a blocking diode in this circuit should work for years. I might tuck a CR123 in a holder inside the case somewhere, with a