Re: [CAD_CAM_EDM_DRO] Teledyne Gurley DRO

abenedro wrote:

>Hi,
>I have a Teledyne Gurley DRO from the 70's which will only read in
>metric although the thumbwheel switches should allow it to read
>imperial as well as metric. I suspect it may have been configured
>this way since new to prevent mistakes as it was off a Swedish milling
>machine used on a Sandvik production line. The readout is a
>Pathfinder model 8770 and uses TTL updown counters (74192) and
>minitrons for the displays.
>
>Anyone got a schematic for this box so I can work it out or heard of
>this before?
>
>

I talked to an old Teledyne Gurley rep quite a few years ago when I
inherited
a pile of DRO bits and pieces. Sometime in the early 70's they went to
all-metric
scales, and stopped production of imperial scales. The older, imperial- or
metric-only readout boxes would then only display the native resolution of
a given scale. I think this is what you've got there, a native-only box and
a metric scale. What Gurley did after that change was to incorporate PROMS
in all readout boxes to perform the metric to imperial conversion. If
your DRO
box only has standard SSI and MSI components like gates and decimal
counters,
it won't do the conversion.

Jon