Blizzard 1260 battery replacement

[wiz12]

I'm looking for some advice regarding battery replacement on a Blizzard 1260 accelerator card. It's a CR2032 battery that has been welded onto the metal holders with two pins onto the pcb.

The battery died but was not leaking so the only way to remove it was with it's metal holder. So now there's two pin holes remaining. Does anyone know can you get a drop in replacement holder for this card?

[indigolemon]

The battery should be a VL2020 - which is rechargeable (and thankfully can't leak). They come with the pins for soldering to the board. You'll find tons on eBay as they're used in BMW keyfobs too.

[Predseda]

http://amigakit.leamancomputing.com/...oducts_id=1241

[wiz12]

The trouble is it's not a VL2020 battery though. It's a non-rechargable CR2032.

[indigolemon]

That's very odd, here's a picture of my 1260 with the original battery:

https://goo.gl/photos/JVCX6qRbmRocnjeDA

And my 1230IV - which also used the same battery:

https://goo.gl/photos/sUejwBtMtQPPHgxS8

I can only assume someone has replaced the VL2020 with a 2032 at some point, was there a diode to prevent the Blizzard trying to charge it?

[wiz12]

It's strange indeed as I bought the card new direct from Power Computing back in the day and every other blizzard card I've seen has a different battery. Unless it was a modification they did on the card. Here's a few photos.

http://tinypic.com/view.php?pic=r1zg3o&s=9#.WPYMKRrTW9I

http://tinypic.com/view.php?pic=vwv78i&s=9#.WPYMURrTW9I

http://tinypic.com/view.php?pic=5bcolc&s=9#.WPYMixrTW9I

[Daedalus]

Both types of battery were used on the 1260s - my 1260 was supplied with a tagged CR2032 too, and the relevant diodes in place. It might have been a revision made by DCE when they took over from phase 5, or it could simply be whatever was cheapest to fit whenever a production run was carried out.

Tagged CR2032s are available (Radionics / RS link), if you wanted to go that route. I fitted a holder to mine and it's a tight squeeze since the holder is significantly larger than the cell by itself. I think this is the one I fitted, but it's out of stock and I needed to cut a small section out of the plastic to get it to fit. There are many similar holders around, just make sure you get one with the correct leg spacing as there are different spacings available.

[wiz12]

Does it matter what type of battery is fitted. Could I fit the VL2020 battery kit or does it have to be non-rechargable?

[Daedalus]

It does matter, yes. The Blizzard will be configured to pass a charging current to the battery if it's intended to have a rechargeable, and to block that current if it's intended to have a non-rechargeable. If you fit a VL2020 to yours without making a modification to the circuit, it won't charge and so will not keep time for more than a week or so. If you fit a CR2032 to one that originally had a VL2020, it will try to charge the battery and risks bursting the cell, which would be very bad.

Bottom line, it's simplest to replace like with like. If you felt up to the conversion, check the application notes for the clock chip and compare it with the Blizzard's board. Chances are that it can be done by simply swapping a diode for a resistor, but I'm not entirely familiar with the circuit so I can't say for sure that there isn't more involved.

[indigolemon]

Ah man, it makes sense they'd swap to CR2032's to make it cheaper to manufacture right enough. I'm now doubting what mine has, but it does look like a VL2020 in the picture.

I'm going to have to open the case again aren't I ...

[Daedalus]

Yeah, or it could've been a newer revision of clock chip that uses less power and so a single CR2032 was sufficient for its expected life (did anyone really think they'd still be being used 20 years later?)

I'm pretty sure it's a VL2020 myself, but go satisfy your curiosity

[wiz12]

Ok, so I gather fitting a new CR2032 holder is the best solution, any ideas where I could find a suitable holder?

[Daedalus]

Farnell appear to have it in stock, though I'm not sure if they have minimum order values for free shipping. As I said, you'll probably have to trim a little of the plastic from the holder to get it to fit, but it should be fine.

[wiz12]

I will probably get that one so. Thought I'm just after finding one from amigakit which might work but it will involve removing one of the legs.

[Daedalus]

That is different - it's intended as a replacement for NiCd or NiMH barrel-type batteries and includes an extra diode to protect the battery from the charging circuit. Including an extra diode in the circuit might cause problems by dropping the voltage too far for the clock chip to work reliably.

There are slimmer holders available also, but it's difficult to find them with the correct leg spacing (~20mm) - most are 27mm which will be very tricky to fit and won't be very well supported.

[wiz12]

Thanks Daedalus, I'll go with what you suggested.

[wiz12]

Finally got around to replacing the holder. It was a tight enough fit but I think it turned out ok. Like Daedalus said I had to shave a bit off the holder. Here'a a few pictures in case anyone is curious how it turned out.

http://oi68.tinypic.com/15d2bnb.jpg

http://oi63.tinypic.com/aky4gl.jpg

[indigolemon]

Glad you got it sorted! Had no idea some of these had shipped with 2032 batteries. At least it'll be a lot easier next time you need to replace it though