Panasonic SC-TM23 Service Manual

Contents

Panasonic SC-TM23 Service Manual Manual pdf 42 page image

4214 Measurements and Adjustments14.1 Cassette Deck SectionMeasurement Condition· Make sure head, capstan and press roller are clean.· Judgeable room temperature 20 ± 5 °C (68 ± 9°F)Measuring instrument· EVM (DC Electronic voltmeter)· Digital frequency counterTest Tape· Tape speed gain adjustment (3 kHz, -10 dB);QZZCWAT14.1.1 Tape Speed Adjustment (Deck 1/2)1. Set the tape edit button to “NORMAL” position.2. Insert the test tape (QZZCWAT) to DECK 2 andplayback (FWD side) the middle portion of it.3. Adjust Motor VR (DECK 2) for the output valueshown below.Adjustment target: 2940 ~ 3060 Hz (NORMAL speed)4. After alignment, assure that the output frequencyof the DECK 1 FWD are within ±60 Hz of the value of theoutput frequency of DECK 2 FWD.Fig.114.1.2 Bias and Erase Voltage Check1. Set the unit “AUX” position.2. Insert the Normal blank tape (QZZCRA) intoDECK 2 and the unit to “REC” mode (use “• REC/STOP” key).3. Measure and make sure that the output is withinthe standard value.Bias voltage for Deck 2 14±4mV (Normal)Erase voltage for Deck 2 80mV (Normal)Fig.2Fig.314.1.3 Bias Frequency Adjustment (Deck 1/2)1. Set the unit to “AUX” position.2. Insert the Normal blank tape (QZZCRA) intoDECK 2 and set the unit to “REC” mode (• use “REC/STOP”key).3. Adjust L1002 so that the output frequency iswithin the standard value.Standard Value: 97 ±8 kHzFig.414.2 Tuner Section14.2.1 AM-IF Alignment1. Connect the instrument as shown in Fig.5.2. Set the unit to AM mode.3. Apply signal as shown in Fig. 5 from AM-SG.4. Adjust Z2602 so that the output frequency ismaximized in Fig.6.