Performance Check and Calibration Procedures
TPG20 Service 1–25
e. Remove the shorting link (jumper) from LK2.
11. Genlock NTSC and PAL
a. Using the Black/Sync signal of the TSG–170A – loop through the
Reference Input on the TPG20 to CH 1 on the oscilloscope.
b. Examine the signal on pin 7 of N59 (74HC4538) using a probe on CH 2
of the oscillocope.
c. Trigger the oscilloscope on the external reference (CH 1).
d. Adjust – RV1 so that the burst gate at N59 pin 7 is centered about the
burst of the input reference.
e. Set TPG20:
FORMAT 525/60 COMPONENT D1/YPrPb
Groups: BARS; SMPTE COLOR BARS 525 D1/YPrPb
f. Connect one of the TPG20 Analog B Outputs to CH 2 of the oscillo-
scope.
g. Adjust – CV1 to obtain the minimum run through rate of the two signals
on the oscilloscope.
h. Hold down the TPG20 SYSTEM button and cycle the TPG20 power off
and back on. The TPG20 display should indicate Factory setup mode.
i. Deselect crystals X5 and X6 using the procedure above in step 4 (i.e.
assign “No crystal” to X5 and X6).
j. Set TPG20:
FORMAT 525/60 COMPOSITE NTSC/D2
Groups: BARS; SMPTE COLOR BARS 525 NTSC/D2
k. Adjust – CV3 for minimum run through of the two signals as observed
on the oscilloscope.
l. Using the Black/Sync signal of the TSG271 – loop through the
Reference Input of the TPG20 to CH 1 on the oscilloscope.
m. Set TPG20:
FORMAT 625/50 COMPOSITE PAL/D2
Groups: BARS; EBU COLOR BARS 625 PAL/D2
n. Adjust – CV2 for minimum run through of the two signals as observed
on the oscilloscope.