6-20. Total Peak and Average Bias Tele-
graph Distortion Test
(e) INPUT SELECT SWITCH to BRIDGING
(f) BAUD RATE SELECTOR to 75.
(g) DISTORTION SELECT to TOTAL PEAK.
(h) TRANSITION SELECT to ALL.
(i) ALARM switch to RESET.
DANGEROUS VOLTAGES are present dur-
ing the preparation of the test circuits speci-
(a) Turn on the power. If the distant station dis-
fied in figures 6-19 and 6-20. Turn all power
tortion analyzer signal lamp does not light, reverse the
switches off before constructing these test
polarity switch. At the transmitting station, transmit
circuits. Failure to observe safety precautions
the message "Quick Brown Fox".
could result in serious injury or death.
(b) At the receiving station, read the total peak
c. Station-to-Station Test. Contact distant station
distortion in percent and record it. The place the dis-
and arrange for one station to act as transmitter and
tortion analyzer ALARM switch to RESET and the
as a receiver. Perform the procedure below and then
DISTORTION SELECTOR to AVERAGE S/M.
reverse roles and repeat the procedure.
(c) At the transmitting station, transmit the
(1) Transmitting Circuit. If the local station is to
message "Quick Brown Fox". The receiving station will
act as transmitter, prepare the transmitting circuit
mad the average displacement of the mark-to-space
shown in figure 6-19 and set the AN/GGM-15(V)1
transitions of the input signal as indicated on the per-
test pattern generator controls as follows:
cent distortion meter. If the mark indicator lamp is on,
(a) Use DATAOUTPUT.
marking bias distortion is indicated. If the space indi-
(b) P-N switch to P.
cator lamp is on, spacing bias distortion is indicated.
(c) DISTORTION SELECT to NO DIST.
Record the results.
(d) LEVEL CODE to 5.
(d) Turn power off at both stations.
(e) CHARACTER LENGTH to 7.
(4) Performance Standards. The maximum total
(f) MESSAGE SELECT to MSG.
peak telegraph distortion permissable is 20%. The
(g) BAUD RATE to 75.
maximum mark or space bias distortion permissable is
(2) Receiving Circuit. If the local station is to act
as receiver, prepare the receiving circuit shown in fig-
Figure 6-19. Station to station total peak and average bias telegraph teat.