WhitakerAudio J C Whitaker 20 W Stereo Audio Amplifier, Руководство пользователя

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20 W Stereo Audio Amplifier
• If an audio source is available, connect it to the right and left channel inputs. A music
source is preferable, since music usually reveals fundamental operational issues. Run the
amplifier with the signal source applied for a period of time and monitor the results.
6.2.1 Auxiliary Power Connector Tests
The purpose of the following tests is to confirm that the preamplifier power supply circuits are
working as expected.
– With the amplifier off, measure the resistance between pin #1 and ground. The reading
should be zero ohms.
– Measure the resistance between pin #9 and ground. The reading should be zero ohms.
– Switch the amplifier on.
– Measure the dc voltage between pin #4 and ground. It should be zero.
– Measure the ac voltage between pins #5 and #6. It should be zero.
– Measure the ac voltage between pins #2 and #3. It should be zero.
– Switch the amplifier off.
– Connect a short (approximately 2-inch) #18 wire between pins #7 and #8 on the auxiliary
power connector. This can be accomplished by simply inserting the wire into the socket.
– Switch the amplifier on.
– After about a minute, carefully measure the dc voltage between pin #4 and ground. It
should be approxi400 V dc.
– Measure the ac voltage between pins #5 and #6. It should be 6.3 V ac.
– Measure the ac voltage between pins #2 and #3. It should be 115 V ac.
– Switch the amplifier off.
– Remove the jumper wire between pins #7 and 8.
Preliminary tests have now been completed. Next, detailed performance measurements should
be made.