Hard to find / expensive ICs

DarrenF

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I've tried to identify and procure a few of any "hard to find" (which usually also means expensive) components on the games I own (or want to own). By "hard to find," I mean it can't be had from any of the common big suppliers (Jameco, Mouser, DigiKey, MCM, etc.) By expensive, I mean "typically goes for $10 or more" each. (I know, a somewhat abritrary definition...)

In addition to all of the Namco customs, I've got:

SC01A, speech generator, used in Gottlieb sound&speech board (Black Hole, Q*Bert and others). $40+

AD561J, DAC, used on Asteroids (and I presume others), about $15.

AM6012, DAC, used on Battlezone (and I'd quess others), $10 or so.

H1809 (I know, not an IC...), high voltage diode, G05 & V2000 monitors, around $10.

What other electronic components on common classic games are difficult to find and/or expensive?
 
TMS9928
LM379S
Pokeys
6502A
6532
74LS491

The list can go on and on....
As far as obsolete stuff is concerned none of the normal places other than jameco will have any of it.
 
Im not positive if its 2mhz but that sounds right. Alot of Atari boards use it and a regular 6502 is not fast enough.

Can't you use a 6502B or a 65C02 instead? I don't think they made a 65C02 with a clock speed under 2MHz... but I could be wrong. Are those hard to find now too? Last I looked they were ~$5 each, but that was probably a few years ago.
 
Yes the B should work and most likely the cmos variant as well.
There's not alot of any of the 40 pin MPU/CPU's laying around. If you do find them they are usually pulls or refurbs. Also, alot of the more expensive chips are getting counterfeited. You have to be carefull where you buy from.
 
I've tried to identify and procure a few of any "hard to find" (which usually also means expensive) components on the games I own (or want to own). By "hard to find," I mean it can't be had from any of the common big suppliers (Jameco, Mouser, DigiKey, MCM, etc.) By expensive, I mean "typically goes for $10 or more" each. (I know, a somewhat abritrary definition...)

In addition to all of the Namco customs, I've got:

SC01A, speech generator, used in Gottlieb sound&speech board (Black Hole, Q*Bert and others). $40+

AD561J, DAC, used on Asteroids (and I presume others), about $15.

AM6012, DAC, used on Battlezone (and I'd quess others), $10 or so.

H1809 (I know, not an IC...), high voltage diode, G05 & V2000 monitors, around $10.

What other electronic components on common classic games are difficult to find and/or expensive?

Most PROMS are getting hard to find, and expensive.
 
Can't you use a 6502B or a 65C02 instead? I don't think they made a 65C02 with a clock speed under 2MHz... but I could be wrong. Are those hard to find now too? Last I looked they were ~$5 each, but that was probably a few years ago.

6502B -- yes but equally rare.

It depends on who's 65C02 you are using.

The Rockwell 65C02 -- no.
The WDC 65C02 -- yes.

Incidently, the WDC 65C02 is -still- in production and can be bought directly from manufacturer.
And so are 65C21's (alternate for 6821) and 65C22's.

-- Ed
 
TMS9928
LM379S
Pokeys
6502A
6532
74LS491

The list can go on and on....
As far as obsolete stuff is concerned none of the normal places other than jameco will have any of it.

9928 are hard to find... 9928A are as easy as your nearest scrapped out TI-99/4A computer.

Pokeys are in Atari 5200s

6532 are in Atari 2600s

I have about 30 of the 74LS491 I picked up surplus and pick up every one of them I can find.

I'm going parts shopping in Silicon Valley here in a couple of weeks. :)

Oh, and for PROMs, I have a bunch of 'em... and of the very hard to find 82S100/PLS100 PLA chips. I program them to be NOS replacement Commodore 64 PLA chips which breathes new life into old computers.

RJ
 
someone needs to find a source for leta chips. Or just make them. I know I found a write up on line where someone made one from modern parts just to see if they could do it.
 
someone needs to find a source for leta chips. Or just make them. I know I found a write up on line where someone made one from modern parts just to see if they could do it.

Give that write-up to JROK.
 
Anybody gone the route of making a PROM to 2716 adapter, and if so, any issues? Got a Ms. Pac board that I'm setting up as a Crush Roller, and considering just making some adapters and dropping in 2716's instead of paying somebody else to burn the PROM's, or spending $150 on an adapter to do it myself.

Given the price of the PROM's, and how much easier it'd be to just erase/burn 2716's as needed (which are much more plentiful), I'm curious whether others have gone that route.

Example: http://www.ksarcade.net/adapter-82s123-eprom-to-2716-eprom-for-bally-32-50-sound.html

That's just for the 82S123, but I'd think you could make one for the 82S126 easily enough, and perhaps for others as well.

Otherwise, the cheapest source I've found for the 82S123's/equivalents is www.arcadechips.com, and I don't think he has the Signetics ones...

For the LM379S, Big Daddy has the LM1875T listed as a replacement, but not sure that's a true drop-in replacement (?) See: http://www.bigdaddy-enterprises.com/electronics/e_ics.htm
 
Anybody gone the route of making a PROM to 2716 adapter, and if so, any issues? Got a Ms. Pac board that I'm setting up as a Crush Roller, and considering just making some adapters and dropping in 2716's instead of paying somebody else to burn the PROM's, or spending $150 on an adapter to do it myself.

Given the price of the PROM's, and how much easier it'd be to just erase/burn 2716's as needed (which are much more plentiful), I'm curious whether others have gone that route.

Example: http://www.ksarcade.net/adapter-82s123-eprom-to-2716-eprom-for-bally-32-50-sound.html

That's just for the 82S123, but I'd think you could make one for the 82S126 easily enough, and perhaps for others as well.

In most cases, an EPROM is simply not fast enough to replace a bipolar PROM. Simtek NVRAM, on the other hand, are plenty fast enough. I've built adaptors and used them before:

simtek2bipolar.jpg
 
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