Hitachi I-28 Service Manual page 9

GENERAL ALIGNMENT INSTRUCTIONS
1. VIDEO I-F ALIGNMENT
TEST EQUIPMENT & CONNECTION (See Fig. 10)
MARKER GENERATOR (35~50MHzZ) -----+----++ Couple loosely to the out put cable of sweep genarator
SWEEP GENERATOR (35~50MHZ) «.--------e eee Connect the resistor (5.6KQ2) and the capacitor
(0.01F) to the test point (TP) of tuner.
OSCI LLOSCOPE aicesbswedey ous vou sheb ay sviesagecedsseneceoceage eee Connect the resistor {100 KQ) to terminal (TP201 ).
BIAS SUPPLY ccccceceecessereseeeesseesceeeceeeneteecensaseeseeeeeeeee Add 2~6V of AGC voltage.
SWEEP MARKER
Adjust 47.25MHz trap 35 ~ 50MHz 47.25MHz, 400Hz 1.203 Adjust so that the signal of 400Hz
coil Modulation in oscilloscope may be minimum.
Adjust 39.75MHz trap 35 ~ SOMHz 39.75MHz, 400Hz L202 Adjust so that the signal of 400Hz
coil Modulation in oscilloscope may be minimum.
Adjust 41.25MHz trap
35 ~ 50MHz 41 -25MHz, 400Hz 204 Adjust so that the signal of 400Hz
coil Modulation in oscilloscope may be minimum.
Adjust video IF 35 ~ SOMHz 44.0MHz, 400Hz 1201 | Adjust so that the signal of 400Hz
coil Modulation in oscilloscope may be maximum.
If the same characteristic as that of Fig. 11 does not appear, readjust STEP 1. ~ STEP 5.
¥ sek 0.0l
SWEEP : 47 25M !OOKHr
GENERATOR
2. 7no3. tM z-
(po~3de) |
SX PCB
ape Al (IF)
TP20l DET.
O OUT PUT
OA4
Sev
®& WHEN USED HT-401 VHF TUNER,
NOT NECESSARY TO CONNECT
5.6K RESISTOR. Fig. 10