Huge IBM 1800 find (and need some help)

Jon Elson elson at
Sat Mar 21 13:25:39 CDT 2015

On 03/21/2015 12:02 PM, Johannes Thelen wrote:
>   I supposed there is some big 380/220VAC transformer somewhere.
A quick look at the FE manual seems to indicate it uses a 
bunch of "medium power converters"
which seem to be modular transformer/rectifier/regulator 
type supplies.  I think these are made
to pull out fairly easily as field replaceable units, so 
that might get the weight down.

I also looked in some 360 docs and they had wildly different 
weights listed for the same box in different 
configurations.  This makes me think these are NOT weights 
of individual cabinets but total system weights in different 
Clearly, the machine in your picture is a larger 
configuration with a number of cabinets added to the CPU box.
> So, my only plan is now to get small items first, make better plan how to disassemble cabinets. Of course I have to label everything and take photos, but I'm sure something could (and surely) forgot... Disassembly is not that bad, power sources out, gate arrays can be removed releasing connectors and hinges.
I'd be very careful about removing "gates".  There will be a 
LOT!!! of wires, and the wire-wrap side of the boards are 
pretty fragile. (This is an SLT machine, build much the same 
as a 360, so I know a fair bit about how those are put 
together.  The gates are not going to be very heavy, it may 
be much better to leave them in place.

The disks are probably ruined from dust accumulation, and 
these disk drives likely have metal (not ceramic) heads, and 
will require a lot of work to get running again.  I think 
these use the same scheme as the 2314, with hydraulic head 
positioners.  They will almost certainly have to be rebuilt 
completely.  I'd clean the tops of the drives carefully 
before opening the lids, and try to be very careful to not 
get any more dirt in there when removing the packs.

it may be a fool's errand to try to get the 2311 drives to 
ever work again, possibly a fairly simple device could be 
built that emulates the signals.  The 2311 and 2314 
"protocol" is extremely simple.


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