AU-X1

Willy6

AK Subscriber
Subscriber
I bought the one on the left from ebay and found the one on the right on cl.it kinda looks like someone's dog pissed on the right one and the left one is in good shape but it is from Japan and is 100v only.20160514_151945.jpg 20160514_102832.jpg 20160514_151937.jpg
 
Double vision.

If you are lucky both will have no blown output transistors on the drivers.

Do you know the dates of manufacture? The later the date, the more factory mods it will have to quell the oscillation problems that the earlier versions made the model famous for.

Judging by the looks of the head amp cards on the more rough version on the right, I assume that one to be a very early X1.

The following came from a thread by johnnyboy70
http://audiokarma.org/forums/index.php?threads/how-to-date-your-sansui-amp.472424/

Two first digits = Assembly line
3rd digit = year (you have to know decade)
4th and 5th digits = month
last 4 digits = serial No.

An example
519120222 =
Assembly line 51
9 = 1969 December
12 = December
0222 = Serial Number
 
Last edited:
Double vision.

If you are lucky both will have no blown output transistors on the drivers.

Do you know the dates of manufacture? The later the date, the more factory mods it will have to quell the oscillation problems that the earlier versions made the model famous for.

Judging by the looks of the head amp cards on the more rough version on the left, I assume that one to be a very early X1.

The following came from a thread by johnnyboy70
http://audiokarma.org/forums/index.php?threads/how-to-date-your-sansui-amp.472424/

Two first digits = Assembly line
3rd digit = year (you have to know decade)
4th and 5th digits = month
last 4 digits = serial No.

An example
519120222 =
Assembly line 51
9 = 1969 December
12 = December
0222 = Serial Number
The rusty one on the right says 238120214 and the other one is 219060364
 
Double vision.

If you are lucky both will have no blown output transistors on the drivers.

Do you know the dates of manufacture? The later the date, the more factory mods it will have to quell the oscillation problems that the earlier versions made the model famous for.

Judging by the looks of the head amp cards on the more rough version on the left, I assume that one to be a very early X1.

The following came from a thread by johnnyboy70
http://audiokarma.org/forums/index.php?threads/how-to-date-your-sansui-amp.472424/

Two first digits = Assembly line
3rd digit = year (you have to know decade)
4th and 5th digits = month
last 4 digits = serial No.

An example
519120222 =
Assembly line 51
9 = 1969 December
12 = December
0222 = Serial Number
I started taking the one from 79 apart and pulled the right heat sink out a and tested those outputs and they all test good but one of them has a low current gain.
 
238120214=1978
219060364=1979

Mine is 2200500022=1980

You seem to have already started on the drivers a bit. Resistors 36 and 37 will almost certainly fall apart if you touch them.
For some reason R36 and R37 get hammered on the 2775 driver boards.
 
Last edited:
238120214=1978
219060364=1979

Mine is 2200500022=1980

You seem to have already started on the drivers a bit. Resistors 36 and 37 will almost certainly fall apart if you touch them.
For some reason R36 and R37 get hammered on the 2775 driver boards.
I read that on Hyperions thread and checked those first thing and they both measured 391k ohms should I replace them anyway?
 
Two others were burned the check this pic out.
the most tedious part for me is getting the parts list together time to do some serious thinking.
 

Attachments

  • 20160517_170136.jpg
    20160517_170136.jpg
    43.4 KB · Views: 83
  • 20160516_162043.jpg
    20160516_162043.jpg
    52 KB · Views: 407
Missing transistor?

The Rapture? ...or someone has used that machine for spares?

Other than that....boy there is some damage done there. Besides the missing transistor there are two toasted resistors I can see.

Did something fall onto the other side of board to short out that part of it I wonder?
Those solder points are very exposed.

What does the trace side of the board look like?

Find any coins inside?

index.php
 
Last edited:
Missing transistor?

The Rapture? ...or someone has used that machine for spares?

Other than that....boy there is some damage done there. Besides the missing transistor there are two toasted resistors I can see.

Did something fall onto the other side of board to short out that part of it I wonder?
Those solder points are very exposed.

What does the trace side of the board look like?

Find any coins inside?

index.php
My wife has me doing other things so haven't gotten around to do more checking but I did take this pic of the trace side.I pulled tr 11 thinking that was the culprit on the smoked resistors but it checked good so must be one of the other ones.we're getting ready to go to Alaska for a week so it'll have to wait till we get back.20160517_182551.jpg
 
I read that on Hyperions thread and checked those first thing and they both measured 391k ohms should I replace them anyway?

The one pictured shows 0.390K ohm = 390 ohm - which is correct, but yes, replace them anyway.
 
Hyperion...What Would be a better more rugged alternative?

Higher wattage? A specific brand? (Vishay military film?)
 
Willy6

Just a head's up regarding the service manual for the X1.

The service manual we all use is for the first version of the X1. You will find that the values of a lot of components in your newer X1 will be different from what the service manual says should be there.

Sansui added a lot of factory upgrades after the instability of the early models was discovered.
These changes were noted only in service bulletins, none of which have surfaced.
(Well one has...but that is another story altogether and won't aid in understanding your X1s as they are now.)

The SM will most likely be closer to your rusty 1978 unit. Your 1979 unit will have, if you are lucky, the upgraded 2772 phono motherboard, which is A LOT different from the first version of the 2772.

Also the documentation shows the 2774 buffer amp board to be loaded with components, when actually later versions of the 2774 board have very few of the components shown in the service manual.

For documentary and educational reasons, if your 1978 X1's 2774 board is similar to the SM, pics of it would be really appreciated.

Happy soldering!
 
Back
Top Bottom