|
|
| The
master Test Frame, or MTF, was the center of operations for a
crossbar office. The Vintage Telephone
Equipment Museum contains two MTF's, one for their Crossbar
#1 office and one for their Crossbar #5 office.
The Crossbar #5
office is equipped with an automatic trouble ticket recorder
which created punched cards that recorded status of key relays
on certain failure conditions. The Crossbar #1 office has only a
lamp field; trouble diagnosis required careful recording of lamp
states on paper sheets. |
|
click
images
for better views
Crossbar
#5 Master Test Frame (MTF) on left, Crossbar #1 MTF at right
Crossbar No. 1
MTF
Crossbar
#1 Master Test Frame (MTF)
Detail of No. 1 MTF console area
Another view of No. 1 MTF console
area
Crossbar No. 1 trouble sheets
Crossbar
No. 5 MTF
Crossbar #5 Master
Test Frame
Flat-spring control
equipment in a Crossbar #5 office MTF
Test console next to author; trouble ticket recorder
at far left of frame; MTF connectors to right.
Detailed view of #5 MTF console area
Partial view of keys, lamps and
jackfields on a Crossbar #5 MTF console
An Autovon TT pad on No. 5 MTF
Crossbar #5 trouble
ticket recorder
Partial view of a trouble ticket
|
BACK
TO CROSSBAR MAIN PAGE
