Hello all !
Someone can help me for give a second life to a big pioneer amplifier ?
It's a chalenge, for sure xD
I will explain the issue. I bought a Pioneer SC56 "dead" for 30euros some days ago, the first thing was to use the parts for a personnal project... But, after reflexion, I want try to solve the issue.
Concerning the amplifier :
The device start nice, all is functionnal.
The "only" problem is the sound, there is nothing on the output.
Mnaual service is the same that the SC65 : https://elektrotanya.com/pioneer_sc-65_sc-1527-k_sc-1522-k_av_receiver.pdf/download.html
No error on the display, there is no UE22 for example (because it is common to see this error when there is no sound on these old devices)...
DSP firmware version is correct (no "xxx" displayed)
I seen or tried:
Nothing is burned.
The amp is in good condition, nothing broken.
I performed many tests, and all tests was realized with a signal on the "PN/IN1" input (RCA, analog) as explained in the sm.
If I follow the analog signal, the signal enter in the "Select input" chip. After that, he goes on the preout RCA and the input of the amp modules. Simple.. But there is nothing on the Preout.
It is strange because the signal path is relatively "simple".
So I checked the DATA (VLSO) and CLOCK (VLSCK) signal on the CN3771 (This is the bridge between the main board and audio board) with my scope... I can see some packets when the amp start (it is the init of the IC), but nothing when I change the volume or change the input! So my idea is that there is a problem between the display board that send the command to the main board, or between the UPD61110 and the PE7008A (the commands sent to the Input select chip is the work of the PE7008A).
I tried to find the signal between the Display board (with the volume rotary) and the Main board on the CN7901 connector, because the two µC communicate between them by this way. I can see packets on the Pin 21, 22 and 13 on CN7901.
There is the UPD61110 µC between the µC on the display boarda dn the PE7008A.
So I resume the signal track for the volume command is :
Rotary volume -> µC display board -> CN7901 -> µC UPD61110 on the main board -> µC (?) PE7008A -> Audio bridge CN3771 -> BD3473 (audio board).
I can see the packets until the CN7901, but after, it is so hard to follow :/
Thats all... So maybe someone can help me ?
Thx a lot !
Someone can help me for give a second life to a big pioneer amplifier ?
It's a chalenge, for sure xD
I will explain the issue. I bought a Pioneer SC56 "dead" for 30euros some days ago, the first thing was to use the parts for a personnal project... But, after reflexion, I want try to solve the issue.
Concerning the amplifier :
The device start nice, all is functionnal.
The "only" problem is the sound, there is nothing on the output.
Mnaual service is the same that the SC65 : https://elektrotanya.com/pioneer_sc-65_sc-1527-k_sc-1522-k_av_receiver.pdf/download.html
No error on the display, there is no UE22 for example (because it is common to see this error when there is no sound on these old devices)...
DSP firmware version is correct (no "xxx" displayed)
I seen or tried:
Nothing is burned.
The amp is in good condition, nothing broken.
I performed many tests, and all tests was realized with a signal on the "PN/IN1" input (RCA, analog) as explained in the sm.
If I follow the analog signal, the signal enter in the "Select input" chip. After that, he goes on the preout RCA and the input of the amp modules. Simple.. But there is nothing on the Preout.
It is strange because the signal path is relatively "simple".
So I checked the DATA (VLSO) and CLOCK (VLSCK) signal on the CN3771 (This is the bridge between the main board and audio board) with my scope... I can see some packets when the amp start (it is the init of the IC), but nothing when I change the volume or change the input! So my idea is that there is a problem between the display board that send the command to the main board, or between the UPD61110 and the PE7008A (the commands sent to the Input select chip is the work of the PE7008A).
I tried to find the signal between the Display board (with the volume rotary) and the Main board on the CN7901 connector, because the two µC communicate between them by this way. I can see packets on the Pin 21, 22 and 13 on CN7901.
There is the UPD61110 µC between the µC on the display boarda dn the PE7008A.
So I resume the signal track for the volume command is :
Rotary volume -> µC display board -> CN7901 -> µC UPD61110 on the main board -> µC (?) PE7008A -> Audio bridge CN3771 -> BD3473 (audio board).
I can see the packets until the CN7901, but after, it is so hard to follow :/
Thats all... So maybe someone can help me ?
Thx a lot !
Last edited:
Update : I followed the SM for the SC76, and in the diag flow, they ask to verify the value of "AMUTE signal" on the audio bridge (same bridge on the two amplifier).
And.. Yep, the signal is HIGH on mine, so the signal is muted. But I don't know why.
I have already performed a factory reset...
Some one here for help ^^ ?
And.. Yep, the signal is HIGH on mine, so the signal is muted. But I don't know why.
I have already performed a factory reset...
Some one here for help ^^ ?
Yes but already performed..
Attached some measures on IC1502. AMUTE on CN1502 (and next connectors) is High if XAMUTE and/or XSMUTE is low.
In my case, XAMUTE is low, and it is attached to PE7008... So now I need to know why the PE7008 send a low signal (maybe when something is wrong on another parts after a checking...)
Attached some measures on IC1502. AMUTE on CN1502 (and next connectors) is High if XAMUTE and/or XSMUTE is low.
In my case, XAMUTE is low, and it is attached to PE7008... So now I need to know why the PE7008 send a low signal (maybe when something is wrong on another parts after a checking...)
