options for replacing failed small ROMs in PDP-11

[rescue]

On 2016-06-24 22:47, Al Kossow wrote:
> On 6/24/16 7:42 PM, Josh Dersch wrote:
>
>> A Data-I/O 29A or 29B will do the job nicely.
>>
>
> and a Unipak I or II like this
> www.ebay.com/itm/301995688339

I have a Data-I/O Series 22 which could do these, plus another burner 
that may do them.  I haven't checked the whole thread, but I'm sure some 
others on here have the equipment to do these too.

Is there a file containing the image ?

You'll need to identify if that chip uses tri-state or open collector 
bipolar PROM.

If DEC didn't completely obliterate the original markings, those would 
be very helpful (i.e. Atari tended to stamp on top of the original chip 
#s, so with some careful examination, you can usually figure out the 
original chip #).

The bipolar PROMs aren't cheap like an EPROM....  depending on the 
source/brand/timing they cost anywhere from $5 to $20+ each.  Then most 
people will usually ask for $5 to $10 to burn one.... or if you are 
really lucky... free....

-- Curt