DEC F-11 (Fonz) processor ceramic chip carriers (PDP-11) on eBay

Pete Turnbull pete at
Wed Sep 21 12:24:21 CDT 2016

On 21/09/2016 15:15, Paul Koning wrote:
>> On Sep 21, 2016, at 1:35 AM, Scott Baker <scott.l.baker at>
>> wrote:
> It says "FOR F-11" and that seems plausible judging by the label on
> the box (KEF-11) shown in one of the photos.  That would make it a
> floating point option.  I don't know if that matches the chips and
> whether all the right pieces are present, though.

The top two in the first picture are a pair of KEF11-AA floating point 
microcode options for an F-11 CPU.  One of those would go in either an 
M8186 KDF11-A (11/23), an M8189 KDF11-B (11/23plus or microPDP-11/23) or 
an M7133 KDF11-U (11/24).

The third chip is a KTF11-AA memory management unit, for any of the above.

You sometimes find a KTF11 with a KEF11 because you need the MMU to use 
the floating point, as the FP microcode uses some of the MMU registers.

Pete Turnbull

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