Sony apr 24 owners manual

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SONE
AUDIO RECORDER

APR-24

OPERATION AND MAINTENANCE MANUAL
2nd EdMon
Serial No. 10001 and Higher

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SAFETY CH ECK-OUT

After repair or service, the following safety checks must be performed before releasing the equipment to the
customer: '

Using one of the three methods outlined below, check the metal trim, metallized knobs, screws, and all other
exposed metal parts for AC leakage.

LEAKAGE TEST

The AC leakage current from any exposed metal part to earth ground, or to any other exposed metal part having
a return to chassis, must not exceed 3.5 mA. Leakage current can be measured by any one of the following

methods:

1. With a commercial leakage tester, such as the Simpson 229 or RCA WT-540A. When using such instruments,
the manufacturers instructions must be followed exactly.

2. With a battery-operated AC milliammeter, such as the Data Precision 245.

3. By using a VOM or battery-operated AC Voltmeter to measure the voltage drop across a 1.5k resistor (see
Figure A). With this resistor value, the limit" indication is 5.25V, and the meter used must have an accurate
low-voltage scale. The Simpson 250 and Sanwa SH-63Trd are suitable passive VOM types. Also, most battery-
operated digital multimeters having a 20 VAC range are suitable for these measurements.

T0 EXPOSED METRL

PRRTS 0N SET
A

H
9

at
0.15 HF :: 1-5K § 1 VOLTMETER
0H5 (5.25 V]

__ ERRTH GROUND

Figure A. Using an AC Voltmeter to check AC Leakage

APR-24