I bought this unit for a low price dead. I was pretty excited when I found a dead fuse. Not so excited when the replacement did not solve the problem. This unit uses a 9 VDC power adaptor. I have read cout the similar models that use 5, 3.3 and 1.8VDC. I have no acces to schematics. There appears to be 7VDC, 3.42VDC and 2.42VDC all over the board. I have not been able to find data on the Logc ICs.
There are opamps that are Marked:
2115
3087B
These opamps all have 7Volts at the supply and a good ground as do the Philips TDA1308. The opamps as well as the headphone amp ICs have 3.4 at all pins except power and ground pins. Also peculiar to me is that two of the polar electrolytic capacitors have 3.4VDC on positive and negative sides.
I am totally stumped and would really like to use this unit.
There are some ICs that I can not find information for. Datasheets could at least help me to determine whether I have power where I should have it.
Some of these ICs are: TH tech NG0588N, NEC 9714 some TI ICs that I am not able to read correctly: LW05A, LWD40A
In the picture with Output jacks, C119 and C120 have voltage on both sides.
Thanks in advance for any help
There are opamps that are Marked:
2115
3087B
These opamps all have 7Volts at the supply and a good ground as do the Philips TDA1308. The opamps as well as the headphone amp ICs have 3.4 at all pins except power and ground pins. Also peculiar to me is that two of the polar electrolytic capacitors have 3.4VDC on positive and negative sides.
I am totally stumped and would really like to use this unit.
There are some ICs that I can not find information for. Datasheets could at least help me to determine whether I have power where I should have it.
Some of these ICs are: TH tech NG0588N, NEC 9714 some TI ICs that I am not able to read correctly: LW05A, LWD40A
In the picture with Output jacks, C119 and C120 have voltage on both sides.
Thanks in advance for any help
