Dreaded acid corrosion - Some success?????

[ajlaird]

Doesn't have to look fantastic, just has to work - unless you are selling it to some real fussy dude.

[goodolddays]

Doesn't have to look fantastic, just has to work - unless you are selling it to some real fussy dude.

+1  .. my fingers are crossed for you Gav .

Hey, you want to do the SMD soldering I'm trying to do on the board from my Logitech wheel ?.. looks to me like you have a much steadier hand than I do 

[Homepin]

That's looking a lot neater. I use a toothbrush and acetone to clean the flux away from the area worked on - be quick and it flushes away the flux and doesn't leave any white residue like metho/alcohol. Be too slow or aggressive with the toothbrush and you risk taking off the screen printing or green soldermask.

This actually works VERY well on modern PCBs as the paints are much tougher but if you are careful the job will look a lot better even on older boards and it makes it so much easier to spot remaining problems.

We are nearly finished the reproduction Bally -35 MPU and will start on a replacement Zaccaria MPU middle of January. We will be able to supply a blank PCB at a very sensible price and you will be able to build up a brand new board based on modern PCB techniques - better plated through holes, tougher solder mask etc and we will even incorporate mods to allow for chips that are no longer available. As far as I am aware nobody has done this before - fully populated replacement boards, sure - but not the supply of a blank board at a bare bones price.

Here is a pic of our Bally MPU nearly ready for the PCB factory (these will be supplied with new strip connectors and a few key parts - target sell price $39):

[ajlaird]

Now that is an interesting development! Nice work, gotta love a replacement PCB.

[Retropin]

was hoping youd chime in Mike..... replacemnet PCB.. .... Bloody good price too!

[Strangeways]

Mike - that's great news !

I enjoy the challenge of repairing old Bally -35 boards (&Stern -200), but this new development of yours is very interesting and I look forward to your progress 

[Pinballer]

The new board is a great idea HomePin.  Any idea on when these will be available?

[Homepin]

The new board is a great idea HomePin.  Any idea on when these will be available?

We are aiming for availability of the Bally -35 about the end of January - we will start the layout of the Zaccaria just before Christmas and hope to have that available about March.

W are not finalising the design of either until we have covered as many bases as possible with 'hard to get parts' and made as many alternative options available of the board as possible. We also need to buy in the 'standard' parts that will be included with each bare board such as connector strips, test switch and 0.22Uh chokes.

It is likely the assembly manual will run to about 30 pages detailing step by step assebly with all the various options explained along the way and then step by step power up instructions to avoid damage and correct any assembly faults.

I'll keep you all updated with our progress.

[ajlaird]

The new board is a great idea HomePin.  Any idea on when these will be available?

We are aiming for availability of the Bally -35 about the end of January - we will start the layout of the Zaccaria just before Christmas and hope to have that available about March.

W are not finalising the design of either until we have covered as many bases as possible with 'hard to get parts' and made as many alternative options available of the board as possible. We also need to buy in the 'standard' parts that will be included with each bare board such as connector strips, test switch and 0.22Uh chokes.

It is likely the assembly manual will run to about 30 pages detailing step by step assebly with all the various options explained along the way and then step by step power up instructions to avoid damage and correct any assembly faults.

I'll keep you all updated with our progress.

Well done, if you can keep it to $39 you will sell a fair few I imagine, even just as spares 'in case'.

[humpalot]

The boards sound great Mike, I'll be buying some for sure.

[Homepin]

Yes we agree, $39 is certainly our ideal target sell price but we will have to crunch the numbers when we have finished product in our hands. Some things like GST really kick the pricing around.

There is already a fairly major issue we are dealing with.

The 6800 micro is getting harder to find easily and so this is affecting its price and the 9602 used as an oscillator is practically impossible to find at all, anywhere, at any price.

It looks like we will have to use a 6802 (they are quite plentiful & still reasonably priced). If we take this route then the 9602 is not required as the 6802 has an inbuilt oscillator and uses a common and inexpensive external crystal. A bonus with this is that the 6810 RAM is also no longer required as it is also inside the 6802 and this RAM is close to the 'battery corrosion zone' anyway. This means that a board builder would have to have, or purchase, a 6802 but we think this is still a managable situation as they are only a few dollars.

It is things like this non-availability that we are doing our best to address as it's no good making a replacement PCB if you can't find the parts to build it!!

[humpalot]

Mike will you offering these boards in full kit format?  e.g. with all the parts required to build them?

Personally I'd like to see these boards offered in original format.

[Homepin]

Mike will you offering these boards in full kit format?  e.g. with all the parts required to build them?

Personally I'd like to see these boards offered in original format.

Yes, we will offer bare board (with a few key parts included) and also 'upgrade packs' to take things to various levels right through to a complete kit of parts with everything you need.

We also would love to see it original but there is not a lot of point in making a PCB using parts that are no longer available, nobody would be able to use them - we are aiming to make it as original as possible but with some modern upgrades - it might be that we add extra jumper pads so you can use all original bits if you have them OR jumper things to suit the available/upgraded parts. That is our current thinking.

Actually it was while sourcing all parts to build the initial run we discovered that people who actually have a couple of the rare IC's in stock want stupid prices for them which would make building the board very expensive and probably kill the entire project so it is all a balancing act between 'as original as possible' and 'what is actually possible economically'

[Strangeways]

I think it is a fair compromise if the board is as original as possible with socketed parts that are readily available and easy to replace. 9602 are hard to track down, 5101 are expensive (if you can find them) and 6800 supply will run out. Even tracking down 2716 / 2732 can be difficult and expensive.

I'm really loooking forward to the release of whatever format is feasable, cost effective and supported. This is great news for people like myself that enjoy restoring machines in this format.

[Skybeaux]

I think it's a good project your embarking on Mike.

9602's have always been a difficult chip to find.....just for the record i have around 150 of them new that i sell at $4 each....i think this is a pretty good price considering the chip is no longer made.

You could also go down this path and use a 74HC4538 in place of the 9602
This guy here has done and documented it http://home.pacific.net.au/~jennyah/4538%20Bally%20Clock.htm
It shouldn't be hard to work into your board design