CIRCUIT CHANGE
DATE
Improve Power Dissipation in Standby
1) D403 changed from 8.2V to 4.7V
2) Add D409 across IC402 pin1 and pin3, anode connect to pin3
3) D404 changed from 1N4007 to 1N5819, Reconnect D404
cathode from IC402 pin1 to pin3
4) R521 changed from 130ohms to 270ohms
5) Add another 1N4007(D550) series in IC502 pin8 and D501 anode,
D550's anode connect to D501's anode
6) C517 changed from 1000uF/6.3V to 1000uF/10V, the purpose is SMPS
ripple bigger than liner power supply, increase reliability
Dec. 03. 08
Improve the Q147 Power Dissipation
1) R186 changed from 10K to 22K
2) R187 changed from 510ohms to 2.2K
Dec. 10. 08
Improve fine adjustment of the volume by remote
1) D551 added
2) Change the interval delay time from 200ms to 100ms in software V1.5
Feb. 09. 09
Oct. 2009
VERSION HISTORY
Change Top Cover & Chassis for better fit
from serial number: H9XC375BEEG04120
Change to 0.5W version and add +8V for MDC Oct. 2010
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