Alignment
instructions from the Zenith Service Manual: models 5S119, 5S126, 5S127, 5S150,
5S151,5S161 (chassis 5516)
1. Output of sig gen to the grid of the 6A8 1st detector and rcvr chassis. Output meter across the spkr leads.
2. Sig gen set to 456kc; adjust the 4 IF xfmr adjusting screws for maximum indication on the output meter. Repeat IF adjustments for maximum accuracy and gain.
3. Reconnect sig gen to the antenna and ground terminals. Sig gen remains set to 456kc.
4. Adjust the wave trap located on the rear of the chassis for minimum output reading.
5. Set sig gen at 6mc. Switch receiver to band B and adjust osc trimmer on tuning gang for correct dial rading. Osc trimmer is the adjustment on the tuning cap nearest the front of the chassis.
6. Set sig gen at 1400kc. Switch rcvr to band A and adjust broadcast trimmer located nearest to the front of the 6A8 tube. Set for correct 1400kc dial reading. Also adjust ant trimmer on the tuning gang for resonance. Ant trimmer is the one on the rear of the tuning cap.
7. Set sig gen at 18mc. Switch receiver to band C and adjust the short wave trimmer while rocking the pointer past 18mc on the dial to the combination giving the greatest output.
8.Set sig gen on 600kc. Switch receiver to band A. Rock pointer past 600 on the dial while adjusting the broadcast padder, which is located between the tuning cap gangs and the 1st IF transormer. Adjust to the combination that gives the greatest output reading.
9. Readjust broadcast and ant trimmers at 1400kc as in operation 6.
The manual makes no mention of connecting the high side of the sig generator to the test point through a capacitor or resistor. Often, such instructions require a cap of .1 mfd when aligning the IFs and broadcast band. When aligning the short wave band, often a resistor of 400 ohms is required in the hot side of the sig gen. Sometimes, the intermediate SW band (police band) is aligned using a small value cap in series with the sig gen hot lead.
1. Output of sig gen to the grid of the 6A8 1st detector and rcvr chassis. Output meter across the spkr leads.
2. Sig gen set to 456kc; adjust the 4 IF xfmr adjusting screws for maximum indication on the output meter. Repeat IF adjustments for maximum accuracy and gain.
3. Reconnect sig gen to the antenna and ground terminals. Sig gen remains set to 456kc.
4. Adjust the wave trap located on the rear of the chassis for minimum output reading.
5. Set sig gen at 6mc. Switch receiver to band B and adjust osc trimmer on tuning gang for correct dial rading. Osc trimmer is the adjustment on the tuning cap nearest the front of the chassis.
6. Set sig gen at 1400kc. Switch rcvr to band A and adjust broadcast trimmer located nearest to the front of the 6A8 tube. Set for correct 1400kc dial reading. Also adjust ant trimmer on the tuning gang for resonance. Ant trimmer is the one on the rear of the tuning cap.
7. Set sig gen at 18mc. Switch receiver to band C and adjust the short wave trimmer while rocking the pointer past 18mc on the dial to the combination giving the greatest output.
8.Set sig gen on 600kc. Switch receiver to band A. Rock pointer past 600 on the dial while adjusting the broadcast padder, which is located between the tuning cap gangs and the 1st IF transormer. Adjust to the combination that gives the greatest output reading.
9. Readjust broadcast and ant trimmers at 1400kc as in operation 6.
The manual makes no mention of connecting the high side of the sig generator to the test point through a capacitor or resistor. Often, such instructions require a cap of .1 mfd when aligning the IFs and broadcast band. When aligning the short wave band, often a resistor of 400 ohms is required in the hot side of the sig gen. Sometimes, the intermediate SW band (police band) is aligned using a small value cap in series with the sig gen hot lead.
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