Batboard

I'm looking for the commercial equivelent part number for U-501; not the Motorola number, thanks

The Motorola chip is usually a 27128A-20. The 27128-20 and 27C128-20 also work. The -20 is the speed specification and a -15 or -10 works just as well because it is just faster which makes no difference.

These are ultra-violet erasable Programmable Read Only Memory chips (i.e. EPROM). If you purchase new/old stock the chip will already be erased. If you get a used one you will need an ultra-violet chip eraser. Then you need a EPROM programmer to program the chip.

http://www.onfreq.com/syntorx/syntorx9k
http://www.onfreq.com/syntorx/prom.html#top_prom

As usual I dug through my desk and turned up 6. I'm needing to burn a couple of t70 dual chips, thanks.