During the coldest winter months I tend to stick to indoor activities instead of freezing while taking pictures. Recently my brother in law gave me this classic Philips GA-212 turntable that was manufactured in Holland. I decided to do a restoration and refurbishment of the turntable a few days ago being vinyl is back in favor these days. It did have a few issues though. It wouldn’t hold its 33 or 45 rpm speeds even when the trim controls were adjusted and the auto stop feature wasn’t working either. Luckily the problem with the speed was solved by opening the turntable up and adjusting a variable resistor in the main board to exactly -9 volts DC (as per the Philips service manual) and the auto stop feature issue was caused by a burnt out light bulb. Did you say light bulb Joe ? Yes I did. The Philips GA-212/312 series use a total of four tiny light bulbs (equivalent to 6 volt flashlight bulbs). The auto turn off feature utilizes a flashlight bulb that illuminates a CDS cell (cadmium sulfide cell) that is sensitive to light. When light illuminates the CDS cell the power is transmitted to either the 33 or 45 rpm touch sensor controls. When the light is blocked from the CDS cell the power is interrupted and the turntable platter stops. But how is the light blocked from the CDS cell Joe ? Philips chose to use a shutter mechanism under the top deck of the turntable that follows the tone arm movement. When the tonearm is at the end of the LP and enters the leadout groove the shutter mechanism blocks the light from the flashlight bulb that illuminates the CDS cell. Now that everything is working properly and the turntable is reassembled all I have to do is change that really sucky sounding cartridge 😊
If you are interested in photography and some audiophile projects check out my site at www.thevisualchronicle.com
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