Simpson 1000 - Page 13

TUBE INFORMATION
4. Pull the paper snugly onto the lower roller when you
fasten the end to it.
5. Place the pair of rollers in the mounting bracket with
the full roll up, toward the panel mounting.
6. Mount the bracket on the front panel again with the four
Phillips head screws, lock-washers and nuts, which
were removed at the beginning of the replacement steps.
7. As a final check, see that you have placed the bracket
so the printing on the chart shows right side up through
the windows, and turn the wheels to roll the chart -
through its entire length - and watch for any binding on
the wheels or on the paper chart at any operating point.
HOW TO READ YOUR ROLL CHART
Tube sequence on your roll chart follows the same se-
quence as the number-letter-number designation of tube
types. Tube types which have two designations show at the
listed point. «For instance, a VR-75 is also known as an
OA; the roll chart lists it as OA3-VR-75.
Tubes which have letter designations only appear at the
end of the list.
For your convenience, the roll chart is set up in two con-
secutive columns with the first half of the list appearing
through the left hand window and the last half through the
right hand window.
HOW-TO-DO-IT EXAMPLE
Figure 3 shows the information appearing on the roll chart
for a 6AG7 tube. This is a pentode with an octal base and
has the following pin connections: filament, 2 and 7; cath-
li