Sansui AU-217 Restoration

[dedero]

Hello,

I'm starting with the restoration of an Sansui AU-217, as far as I could see, the restorations and recap aren't quite often so I would also like to post how everything goes as well.

I would like to ask you guys regarding the PSU capacitors (6800uf 50V), the thing is the original ones have 4 connectors and the polarity connections have 20mm of lead space but the new caps (I didn't bought any yet but I would like to replace the originals with Nichicon KG series) have 10mm, so I'm a bit stuck here.

I saw some people from different models modify the board to attach snap-in connections (I don't really like to modify the board) and another guys attach the lug type connections but I'm not sure how they do that, some others replace the original interior with new ones keeping the original external capacitor shape.

Any help here??.

Thanks and cheers,
Bruno.

 

[AUD101]

For the AU-217 and AU-217II - the original 6800uF 50V PSU Electrolytics are 4-pin snap-ins - 35mm diameter - 60mm height - lead spacing of 22.5mm

Current possible replacement's are
NOS Panasonic TH-A 8200uF 80V - drop-in replacements currently in stock at Mouser Electronics
or Nichicon UKW 6800uF 50V also currently in stock at Mouser Electronics - these are leaded which can be bent to the correct required lead spacing

 

[smurfer77]

Keep it coming OP. I use to own an AU-217 and thought it was a little champ with sound that embarrasses many of the bigger models. And, we don't see much of the Au-217 on AK as folks are generally more into the higher-powered models or 'TOTL', which I think is a big shame.

 

[dedero]

For the AU-217 and AU-217II - the original 6800uF 50V PSU Electrolytics are 4-pin snap-ins - 35mm diameter - 60mm height - lead spacing of 22.5mm

Current possible replacement's are
NOS Panasonic TH-A 8200uF 80V - drop-in replacements currently in stock at Mouser Electronics
or Nichicon UKW 6800uF 50V also currently in stock at Mouser Electronics - these are leaded which can be bent to the correct required lead spacing

Thanks a lot!, I will go for the Panasonic ones because I really like the drop-in replacements.

I will post further news!

Cheers,
Bruno.

 

[jd-audio]

I also like the AU-217, nice to hear you are putting in time, money and effort to reconditioning one.

Recently I cleaned some AU-217 toggle switches by using the method described by AK memer Kale (Ithink): Completely reassemble the switch, taking out the small contact parts and cleaning all. Even needed a donor switch as one of the smal contact parts was deformed.
PITA job but great results, superquiet switching for many years to come.

Good luck and keep posting
-John-

 

[dedero]

I also like the AU-217, nice to hear you are putting in time, money and effort to reconditioning one.

Recently I cleaned some AU-217 toggle switches by using the method described by AK memer Kale (Ithink): Completely reassemble the switch, taking out the small contact parts and cleaning all. Even needed a donor switch as one of the smal contact parts was deformed.
PITA job but great results, superquiet switching for many years to come.

Good luck and keep posting
-John-

Hi John, thanks for sharing your experience! Can I ask you more information about this method? I was searching in the forum and I could not find anything. Thanks!
Bruno

 

[jd-audio]

will

Hi John, thanks for sharing your experience! Can I ask you more information about this method? I was searching in the forum and I could not find anything. Thanks!
Bruno

Hi Bruno,
Follow this link and you know what I mean.
http://www.audiokarma.org/forums/index.php?threads/another-sansui-au20000.699933/page-3

Be aware that you must have patience, a steady hand, a looking glass and a good eyesight (to look for the parts that fall on the floor and seem te be invisable untill you crush them with your foot) to dis-/re-assemble the switches (did I mention patience?).

Have fun
-John-

 

[dedero]

Hey guys,

I would like to post some progress about this restoration, this is my first one so probably I won't have as much details as expected!

First, some pictures some minutes after I received the amp:

AU217_Dirty

• dedero
• Feb 13, 2017

http://audiokarma.org/forums/index.php?threads/sansui-au-217-restoration.755714/

AU217_Dirty2

• dedero
• Feb 13, 2017

http://audiokarma.org/forums/index.php?threads/sansui-au-217-restoration.755714/

The amp itself:

AU217_front

• dedero
• Feb 13, 2017

http://audiokarma.org/forums/index.php?threads/sansui-au-217-restoration.755714/

AU217_back

• dedero
• Feb 13, 2017

http://audiokarma.org/forums/index.php?threads/sansui-au-217-restoration.755714/

Some leaking caps, there were several but I took a picture on these only:

AU217_leakingcaps

• dedero
• Feb 13, 2017

http://audiokarma.org/forums/index.php?threads/sansui-au-217-restoration.755714/

After cleaning, it seems the guy was using it as notebook holder or something like that because there were some sticky sweet alike dirty:

AU217_inside_prev

• dedero
• Feb 13, 2017

http://audiokarma.org/forums/index.php?threads/sansui-au-217-restoration.755714/

Recap-Restoration starts here:

AU217_nakedfront

• dedero
• Feb 13, 2017

http://audiokarma.org/forums/index.php?threads/sansui-au-217-restoration.755714/

I removed, dissasembled and cleaned every switch (thanks John (jd-audio) for the details!):

AU217_switch_disasembly

• dedero
• Feb 13, 2017

http://audiokarma.org/forums/index.php?threads/sansui-au-217-restoration.755714/

Before switch cleaning:

AU217_switchbeforecleaning

• dedero
• Feb 13, 2017

http://audiokarma.org/forums/index.php?threads/sansui-au-217-restoration.755714/

After switch cleaning:

AU217_aftercleaning

• dedero
• Feb 13, 2017

http://audiokarma.org/forums/index.php?threads/sansui-au-217-restoration.755714/

I tried to disassemble all potentiometers but I couldn't make it... the volume and input switch looked a bit complex to be disassembled so I went for cleaning without disassemble (if you have any link regarding how to disassemble them, I will be very thankful!)

 

[dedero]

Some old vs new caps, I replaced all of them, I used Nichicon MUSE, KZ and FG series and ELNA Silmic II:

AU217_capscompare

• dedero
• Feb 13, 2017

http://audiokarma.org/forums/index.php?threads/sansui-au-217-restoration.755714/

AU217_capscompare2

• dedero
• Feb 13, 2017

http://audiokarma.org/forums/index.php?threads/sansui-au-217-restoration.755714/

Thanks AUD101 for the details about power supply caps, I decided to go for the Nichicon instead of the drop-in replacement

AU217_filtercaps

• dedero
• Feb 13, 2017
• 1

http://audiokarma.org/forums/index.php?threads/sansui-au-217-restoration.755714/

Deadly glue!, I decided to remove it mecanically and after 3hours and some small scratches, most of it was gone. I read to remove it with thinner but I wasn't so safe with it, if somebody has any better way, it will be really appreciated!, I was so frustrated with the glue that I forgot to take any picture afterwards:

AU217_gluebefore

• dedero
• Feb 13, 2017

http://audiokarma.org/forums/index.php?threads/sansui-au-217-restoration.755714/

Nichicon MUSE over the cleaned circuit board:

AU217_newnichiconmuse

• dedero
• Feb 13, 2017

http://audiokarma.org/forums/index.php?threads/sansui-au-217-restoration.755714/

Varistors VD1212 retrofitted with 2 x 1N4148 in series

AU217_varistorreplacement

• dedero
• Feb 13, 2017
• 2

http://audiokarma.org/forums/index.php?threads/sansui-au-217-restoration.755714/

Power supply caps in their final resting place:

AU217_newfiltercaps

• dedero
• Feb 13, 2017

http://audiokarma.org/forums/index.php?threads/sansui-au-217-restoration.755714/

Fuse resistors replaced:

AU217_Fuse_resistors

• dedero
• Feb 13, 2017

http://audiokarma.org/forums/index.php?threads/sansui-au-217-restoration.755714/

AU217_newfuseresistors

• dedero
• Feb 13, 2017

http://audiokarma.org/forums/index.php?threads/sansui-au-217-restoration.755714/

To be done: Replace BIAS timmer pots (I have to pick them up today) and replace old white thermal paste

I'll keep you posted!

 

[smurfer77]

Excellent pics. You are going to have one sweet machine when you are done. Have you been powering it up now and again to check it is still working properly after each stage?

Cheers

 

[AUD101]

dedero - looking good! - Here's a method for glue removal from forum member Kico ---> My solution for easy AU-717 Sansui glue removal
Depending how far you want to go with your AU-217 restoration - you could also change out the speaker relay too

 

[ghamilton]

 

[dedero]

dedero - looking good! - Here's a method for glue removal from forum member Kico ---> My solution for easy AU-717 Sansui glue removal
Depending how far you want to go with your AU-217 restoration - you could also change out the speaker relay too

Awesome! thanks for the details!, I will keep in mind for the next restoration.
Actually I was thinking about changing the speakers relay but I thought the replacement is only when the relay itself doesn't work, but now you are mention it, would be a good idea as well

Excellent pics. You are going to have one sweet machine when you are done. Have you been powering it up now and again to check it is still working properly after each stage?

Cheers

Thanks!, Actually yes, I was testing the amp several hours just at low volumes due to the "brake in" process

 

[UptheIrons]

He hello nice post about the 217. i am about to do the same with my own recently bought AU-217.
Do you have an list or something where you put all your capacitors?

it would be very helpfull!

 

[dedero]

Hi!, I'm sorry for replying one year later... actually I'm not receiveing e-mail notifications and I'm not sure why...

Part list, true, that's something I forgot to post, here we go:

Equalizer Board F-2758
Equalizer Board C01 1 uF 50 V - REPLACED
Equalizer Board C02 1 uF 50 V - REPLACED
Equalizer Board C05 100 uF 6.3 V - REPLACED
Equalizer Board C06 100 uF 6.3 V - REPLACED
Equalizer Board C13 47 uF 10 V - REPLACED
Equalizer Board C14 47 uF 10 V - REPLACED
Equalizer Board C15 3.3 uF 50 V - REPLACED
Equalizer Board C16 3.3 uF 50 V - REPLACED
Equalizer Board C617 220 uF 35 V - REPLACED
Equalizer Board C618 220 uF 35 V - REPLACED
Equalizer Board C619 220 uF 35 V - REPLACED

Power Supply, Protector Circuit y Power Amp Board F-2760
Power Amp Board C01 1 uF 50 V - REPLACED
Power Amp Board C02 1 uF 50 V - REPLACED
Power Amp Board C07 47 uF 50 V - REPLACED
Power Amp Board C08 47 uF 50 V - REPLACED
Power Amp Board C09 330 uF 50 V - REPLACED
Power Amp Board C10 330 uF 50 V - REPLACED
Power Amp Board C11 47 uF 6.3 V - REPLACED
Power Amp Board C12 47 uF 6.3 V - REPLACED
Power Amp Board C15 330 uF 50 V - REPLACED
Power Amp Board C16 330 uF 50 V - REPLACED
Power Amp Board C23 100 uF 6.3 V - REPLACED
Power Amp Board C24 100 uF 6.3 V - REPLACED
Power Amp Board C25 100 uF 6.3 V - REPLACED
Power Amp Board C26 100 uF 6.3 V - REPLACED
Power Amp Board C27 1 uF 50 V - REPLACED
Power Amp Board C28 1 uF 50 V - REPLACED
Power Amp Board C29 470 uF 6.3 V - REPLACED
Power Amp Board C30 470 uF 6.3 V - REPLACED
Power Amp Board C601 47 uF 6.3 V BIPOLAR - REPLACED ***KEEP BIPOLAR IN MIND***
Power Amp Board C602 1 uF 50 V BIPOLAR REPLACED ***KEEP BIPOLAR IN MIND***
Power Amp Board C604 470 uF 6.3 V - REPLACED
Power Amp Board C605 47 uF 50 V - REPLACED
Power Amp Board C606 470 uF 50 V - REPLACED
Power Amp Board C607 470 uF 50 V - REPLACED
Power Amp Board C608 100 uF 50 V - REPLACED
Power Amp Board C609 100 uF 50 V - REPLACED
Power Amp Board C610 100 uF 50 V - REPLACED
Power Amp Board C611 100 uF 50 V - REPLACED
Power Amp Board C612 6800 uF 50 V - REPLACED
Power Amp Board C613 6800 uF 50 V - REPLACED
Power Amp Board C621 3.3 uF 50 V - REPLACED
Power Amp Board C622 3.3 uF 50 V - REPLACED
====FUSE RESISTORS START=====
Power Amp Board R39 220 ohm 1/4 W - REPLACED
Power Amp Board R40 220 ohm 1/4 W - REPLACED
Power Amp Board R41 220 ohm 1/4 W - REPLACED
Power Amp Board R42 220 ohm 1/4 W - REPLACED
Power Amp Board R43 6.8 ohm 1/4 W - REPLACED
Power Amp Board R44 6.8 ohm 1/4 W - REPLACED
Power Amp Board R45 6.8 ohm 1/4 W - REPLACED
Power Amp Board R46 6.8 ohm 1/4 W - REPLACED
====FUSE RESISTORS END=====
Power Amp Board VS01 VD1212 - 2 x 1N4148 in serie - REPLACED
Power Amp Board VS02 VD1212 - 2 x 1N4148 in serie - REPLACED

Tone Control Board F-2759
Balance - Tone Control Board VR01 250 k ohm - CLEANED
Volume - Tone Control Board VR02 250 k ohm - CLEANED

2 x Trimpots 470ohm --> extremely difficult to get... one year later and I cannot get it anywhere... the original trimpots were fine to tune the BIAS current

Speaker relay: Omron MY4-02 DC24 - REPLACED

 

[dedero]

Hi All,
I came back again to ask you guys something regarding the speakers relay, the thing is the relay was the last thing to replace, the thing is since the very beginning (I forgot to post earlier) with the new relay, when I turn on/off the amp there is a quite loud "pop", I'm considering cleaning the original one and put it back again...

Any other suggestions will be appreciated!

Thanks and cheers,
Bruno.

 

[Hyperion]

I'm considering cleaning the original one and put it back again...

When these relays fail, they do so usually because of eroded/worn/badly tarnished contacts, once the contact plating is gone the only cure is relay replacement.

 

[roger2]

......

2 x Trimpots 470ohm --> extremely difficult to get... one year later and I cannot get it anywhere... the original trimpots were fine to tune the BIAS current

.....

.....

Any other suggestions will be appreciated!

Thanks and cheers,
Bruno.

Are you having trouble finding trimpots because 470ohm is not available? Perhaps you could find and use 500ohm instead?

I always replace trimpots during a refurb. The older ones are likely open case, as opposed to sealed like their replacements would (should) be, and the materials are inferior to materials in modern trimpots. With a refub as thorough as the one you have done, IMO the old trimpots are by far the weakest link among remaining components.

I believe that 500ohm trimpots could be used in place of 470ohm without any functional issues. Could someone please either confirm or deny?

 

[Leestereo]

...when I turn on/off the amp there is a quite loud "pop"...

Measure the DC offset at the speaker terminals; based on your description, it is likely to be high. If that is the case, the differential input pair IC (2SA798) of the power amplifier stage is failing.

 

[Hyperion]

I believe that 500ohm trimpots could be used in place of 470ohm without any functional issues. Could someone please either confirm or deny?

Confirmed - no issues there.