CFD-Z500, CFD-Z501, CFD-Z550 - Sony Audio Service Manual (repair manual). Page 3

– 3 –

S801

To Exposed Metal
Parts on Set

0.15µF

1.5k

Ω

AC
voltmeter
(0.75V)

Earth Ground

After correcting the original service problem, perform the following
safety check before releasing the set to the customer:
Check the antenna terminals, metal trim, “metallized” knobs, screws,
and all other exposed metal parts for AC leakage. Check leakage as
described below.

The AC leakage from any exposed metal part to earth ground and
from all exposed metal parts to any exposed metal part having a
return to chassis, must not exceed 0.5 mA (500 microamperes).
Leakage current can be measured by any one of three methods.

1. A commercial leakage tester, such as the Simpson 229 or RCA

WT-540A. Follow the manufacturers’ instructions to use these
instruments.

2. A battery-operated AC milliammeter. The Data Precision 245

digital multimeter is suitable for this job.

3. Measuring the voltage drop across a resistor by means of a VOM

or battery-operated AC voltmeter. The “limit” indication is 0.75
V, so analog meters must have an accurate low-voltage scale. The
Simpson 250 and Sanwa SH-63Trd are examples of a passive
VOM that is suitable. Nearly all battery operated digital
multimeters that have a 2V AC range are suitable. (See Fig. A)

On repairing CD section, playing a disc without the CD lid, use
Chuck Plate Jig.
• Code number of Chuck Plate Jig: X-4918-255-1

1. Turn on POWER button and press CD button to CD position.
2. Open the CD lid.
3. Turn on S801 as following figure.
4. Press the 

( P (CD) button.

5. Confirm the laser diode emission while observing the objecting

lens. When there is no emission, Auto Power Control circuit or
Optical Pick-up is broken.
Objective lens moves up and down three times for focus search.