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There are currently no product reviews.
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Even if the PDF is a scan, I can read the information I need.
The price is affordable and the service (mail sending) is very fast.
Thanks ! Regards. William (Fan of Kenwood)
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Very good quality original datasheet!I like this amazing website!!!!!!
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Excellent just what I needed to replace the electrolytic caps and make this old gem a beauty again. Was as scan of the original photocopied service manual.
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It was helpful to get schematic with waveforms in important points and lot of service information. Manual is good quality, fast delivered. Of course it is hardcopy of paper one with all its disadvantages.
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I want to give you a real heads-up for your desire to enable such people as I to acquire the information I need to maintain the older types of equipment such as this Akai HXA351W. You do a swell job with all the processes you have to perform so I can have a legible, thus usable
document which does not send me crazy trying to figure out the blurry text of a bad copy.
Very well done, Thomas.
KV-27S42/27S46/27S66/29AL42/29AL42C/29AL66/ 29AL66C/29SL42/29SL42C/29SL46/29XL42M
SAFETY CHECK-OUT
After correcting the original service problem, perform the following safety checks before releasing the set to the customer: 1. Check the area of your repair for unsoldered or poorly soldered connections. Check the entire board surface for solder splashes and bridges. 2. Check the interboard wiring to ensure that no wires are �pinched� or touching high-wattage resistors. 3. Check that all control knobs, shields, covers, ground straps, and mounting hardware have been replaced. Be absolutely certain that you have replaced all the insulators. 4. Look for unauthorized replacement parts, particularly transistors, that were installed during a previous repair. Point them out to the customer and recommend their replacement. 5. Look for parts which, though functioning, show obvious signs of deterioration. Point them out to the customer and recommend their replacement. 6. Check the line cords for cracks and abrasion. Recommend the replacement of any such line cord to the customer. 7. Check the B+ and HV to see if they are specified values. Make sure your instruments are accurate; be suspicious of your HV meter if sets always have low HV. 8. Check the antenna terminals, metal trim, �metallized� knobs, screws, and all other exposed metal parts for AC leakage. Check leakage as described below. Leakage Test 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 microampere). 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 instructions. 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�s 250 and Sanwa SH-63Trd are examples of passive VOMs that are suitable. Nearly all batteryoperated digital multimeters that have a 2 VAC range are suitable (see Figure A).
How to Find a Good Earth Ground A cold-water pipe is guaranteed earth ground; the coverplate retaining screw on most AC outlet boxes is also at earth ground. If the retaining screw is to be used as your earth ground, verify that it is at ground by measuring the resistance between it and a cold-water pipe with an ohmmeter. The reading should be zero ohms. If a coldwater pipe is not accessible, connect a 60- to 100-watt trouble light (not a neon lamp) between the hot side of the receptacle and the retaining screw. Try both slots, if necessary, to locate the hot side on the line; the lamp should light at normal brilliance if the screw is at ground potential (see Figure B).
Figure A. Using an AC voltmeter to check AC leakage.
Figure B. Checking for earth ground.
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