Builds keep crashing. Now down to the BARE machine with the instruction set.
Rebuilding hardware with revised bypass capacitors, and new IC's.
A revised ALU card, runs the 99,999 bottles of beer program in about 24 hours
with no problem. I plan to build a duplicate set of cards for more testing.
Perhaps in time I will have a spare machine to give to a good home.
Ben.

Still have noise problems, so it just works on lucky days.I need to revise the display panel
and other PCB's so will be testing more when I get boards in.While waiting for that I hope
to have a 13x10x6.5 inch wooden box, modified to hold the computer.

Redesigned the motherboard,now 4 layer and I hope better bus termination.
Have to wait now for that PCB.

Got a wooden case off amazon and put in all the holes needed and front panel cut out.Wasted a lot of money on tools and parts that did not work or fit right.
Covered most of the inside with copper foil to shield the cpu boards from noise and now waiting the paint to dry on the chassis.I plan to have the new front panel installed this weekend.
Ben.

I needed to mount the ribbon cables from the bottom, not the top.
Time for a revised PCB, and more switched on backorder.

Testing a new alu card. This is a smaller 4 layer PCB.
Not quite a TTL computer. CMOS 1508,74LS14,74LS219,7H04.

Computer in a BOX, testing 99 bottles of beer.
Need to build the new Mother board and front panel.

Shipping problems.
Testing what I have,I'll look for the missing buttons later.

Crashed again. I am thinking heat problems as it is hot in the room here, so I added some stick on heat sinks.
Have some digital thermometers on order.
As a side node the panel push button buttons keep falling off.

Added a FAN for cooling.
Tweaked the micro-code, for I hope better power usage.
Air temp 28C outside the box, 31C inside the box.
177,357 bottles of beer and dropping.

Stripped the logic back down to a 1970's version.
Now testing it out.

I have made it from 1970, 1.65 uS memory cycle
to 1972. 1.25 uS memory cycle. Need to use 74F219's here.
Almost as fast as PDP 8/e.
Heat testing it now.
Ben.
Note no short addressing form, for indexed memory so most instructions
are 3 cycles long where the PDP8 are 2 cycles.

Now at PDP-9 speeds.
1 uS memory access time.

Still need the 74F219's but going to 12 mhz clock, from a 16 Mhz clock.
This gives a memory cycle 1.33 uS. A typical instruction is 3 memory cycles or 4. uS.
Ball park PDP 8/e speeds.
Ben.
P.S. Going with Komputer 1973 as Prom's and 4K drams came out at this (summer 73) time.

And here is Komputer 1973, live.

Need to wait for parts, for 1.33 uS.
Current test version is 1 uS core cycle.
Over the week end I plan to try a new mother board.