@Vintage Audio Fan sir while adjusting bias reading is not showing in the multi meter, While adjusting VR 03 we are able to hear the sound change but cannot be maintain the multi meter, technicians are unable to solve the issue, while we switch on the amp, disturbances are heard, tell us a way to solve the bias issue.
From your description the bias can't be adjusted by VR03, it seems the bias circuit is not working properly. I suggest to check if there are correct voltage (2.2V) on collector of TR05 (2SA899) and voltage (-1.8V) on emitter of TR06 (2SC945) as shown in circuit diagram. The voltage at these location are very important which will decide if the bias works properly. You can check all the components connect to these two transistors if the voltage doesn't work as shown in schematics. Hope it will help solving your problem.
I have au 517, Could you tell me how to adjust bias, In what positions should the amp switches and volume, bass treble switches we set while adjusting VR 01,VR 02, In what position should tone, subsonic filter, loudness be maintained. The Reading is 0 while adjusting VR03, No change is shown.What are the criterias to be followed while adjusting VR03.
I suggest to remove the connectors between pre-out and main-in (at back panel) when adjusting power amp DC offset and bias. So it doesn't matter what positions the controls/switches are in, as long as you don't apply any signal source into power amplifier while adjusting VR01, VR02 & VR03. The reading should be 0V (or near 0V) between speaker terminals for DC offset by adjusting VR01 & 02. And the reading should be 19-21mV between TP (test points on PCB) for bias (idling current) by adjusting VR03. If the reading stays 0V and can't be adjusted with VR03, it means the bias circuit is defective and it needs repair.
I have the same problem with mine. Thinking about a total rebuild. Are the kits on eBay from a reputable seller any good? He does have good feedback on almost everything he sells! Hifi audio rocks is the seller?
I would be very very careful dealing with ebay sellers. My experience with a seller went completely pear shaped. He had great reviews, however, was not true to his word and ebay did not resolve my problem nor did they publish the negative review I left for seller. Purchase replacement parts from Mouse or another reputable supplier.
Hola tengo un Sansui 517 y le contamos un mezclador y Queiro saber si se puede conectar una planta y como hacerlo en tu vídeo no me dejas ver la parte de atrás hemos intentado conectar la planta pero no nos da el sonido nos puedes esplicar soy de colombia te agradecería nos esplicaras gracias
Sorry, I guess you are asking how to connect a guitar to a Sansui 517. There is an article may help: guitaristnextdoor.com/can-you-hook-up-a-guitar-amp-to-a-stereo/
Hello, I've got a cheap AU 417, seems to be about half of the stuff that's inside yours. Mine is not working also, I've got sound (but distorted) on all right channels (also on Headphones right side), on all left channels theres nothing except when you turn it almost to the max than you can hear just very fizzling and quiet sound of the music. From a first inspection there is no obvious fault, do you have got an Idea for me where to look at? Would appreciate it very much, thank you!
The AU series of Sansui are the integrated type of amplifiers which include the pre-amplifier and power amplifier sections. To troubleshoot this type of amplifiers, first step is to isolate the origin of the problems. I always suggest to test the pre-amp and power amp separately in order to pinpoint the location. There are some elements may cause the weak outputs of sound: (1) Signal path from input sources to output speaker terminals which include the wiring, PCB traces, solder joints, controls and switches. Any bad contacts will weaken the outputs of sound. I suggest to check the entire wiring, PC boards and clean all switches by using elec. contact cleaner (2) The other weakest link is the coupling capacitors. You can check these capacitors on PC boards and make sure they are in good condition or just replace them since they are already 40 yrs. old. (3) The aged transistors may have leaks between base, collector and emitter. It will cause no outputs or distortion of outputs. It requires the experienced tech. to diagnose the circuit by using more sophisticated equipment. I hope the above information will help.
The issues with AU-517 I had before were: (1) Defective fusing resistors in poweramp caused the high DC offset (speaker relay won't kick in). (2) Leaked pre-amp's phono input stage differential dual transistors (caused the pop noise when play phono) - see my other video. I suggest re-cap the whole pre-amp's, power amp's and power supply's PCB. Also replacing the parts I listed above. If you can upgrade the transistors and install new zener diodes will be a big plus too.
Recently, I found one AU 517 at local Goodwill store. There are no issues for the amp. Can you recommend what area that I should check to prevent future malfunction ? When you adjust the bias, do you connect a dummy load at the output or leave it open ?
Base on my experiences, the following area needs attention are (1) Power supply regulator transistors include: TR01/02 (2SD438) and TR03/04 (2SB560) in PCB F-2675 (power supply), (2) Differential transistors include TR01/02/05/06 (2SA906) in PCB F-2723 (phono amp) and (3) Dual FET 01 (2SK97) in PCB F-2721/F-2722 (power amp). It probably should connect a dummy load at output to adjust bias but I usually leave it open. I will suggest to follow MFR's service manual if it said so.
Eu também tenho um SANSUI au517 e realmente tem uma excelente qualidade de SOM...
@Vintage Audio Fan sir while adjusting bias reading is not showing in the multi meter, While adjusting VR 03 we are able to hear the sound change but cannot be maintain the multi meter, technicians are unable to solve the issue, while we switch on the amp, disturbances are heard, tell us a way to solve the bias issue.
From your description the bias can't be adjusted by VR03, it seems the bias circuit is not working properly. I suggest to check if there are correct voltage (2.2V) on collector of TR05 (2SA899) and voltage (-1.8V) on emitter of TR06 (2SC945) as shown in circuit diagram. The voltage at these location are very important which will decide if the bias works properly. You can check all the components connect to these two transistors if the voltage doesn't work as shown in schematics. Hope it will help solving your problem.
I have au 517, Could you tell me how to adjust bias, In what positions should the amp switches and volume, bass treble switches we set while adjusting VR 01,VR 02, In what position should tone, subsonic filter, loudness be maintained.
The Reading is 0 while adjusting VR03, No change is shown.What are the criterias to be followed while adjusting VR03.
I suggest to remove the connectors between pre-out and main-in (at back panel) when adjusting power amp DC offset and bias. So it doesn't matter what positions the controls/switches are in, as long as you don't apply any signal source into power amplifier while adjusting VR01, VR02 & VR03. The reading should be 0V (or near 0V) between speaker terminals for DC offset by adjusting VR01 & 02. And the reading should be 19-21mV between TP (test points on PCB) for bias (idling current) by adjusting VR03. If the reading stays 0V and can't be adjusted with VR03, it means the bias circuit is defective and it needs repair.
I have the same problem with mine. Thinking about a total rebuild. Are the kits on eBay from a reputable seller any good? He does have good feedback on almost everything he sells! Hifi audio rocks is the seller?
I would be very very careful dealing with ebay sellers. My experience with a seller went completely pear shaped. He had great reviews, however, was not true to his word and ebay did not resolve my problem nor did they publish the negative review I left for seller. Purchase replacement parts from Mouse or another reputable supplier.
Thanks for most expensive information.
Hola tengo un Sansui 517 y le contamos un mezclador y Queiro saber si se puede conectar una planta y como hacerlo en tu vídeo no me dejas ver la parte de atrás hemos intentado conectar la planta pero no nos da el sonido nos puedes esplicar soy de colombia te agradecería nos esplicaras gracias
Sorry, I guess you are asking how to connect a guitar to a Sansui 517. There is an article may help: guitaristnextdoor.com/can-you-hook-up-a-guitar-amp-to-a-stereo/
Hello,
I've got a cheap AU 417, seems to be about half of the stuff that's inside yours. Mine is not working also, I've got sound (but distorted) on all right channels (also on Headphones right side), on all left channels theres nothing except when you turn it almost to the max than you can hear just very fizzling and quiet sound of the music. From a first inspection there is no obvious fault, do you have got an Idea for me where to look at? Would appreciate it very much, thank you!
The AU series of Sansui are the integrated type of amplifiers which include the pre-amplifier and power amplifier sections. To troubleshoot this type of amplifiers, first step is to isolate the origin of the problems. I always suggest to test the pre-amp and power amp separately in order to pinpoint the location. There are some elements may cause the weak outputs of sound: (1) Signal path from input sources to output speaker terminals which include the wiring, PCB traces, solder joints, controls and switches. Any bad contacts will weaken the outputs of sound. I suggest to check the entire wiring, PC boards and clean all switches by using elec. contact cleaner (2) The other weakest link is the coupling capacitors. You can check these capacitors on PC boards and make sure they are in good condition or just replace them since they are already 40 yrs. old. (3) The aged transistors may have leaks between base, collector and emitter. It will cause no outputs or distortion of outputs. It requires the experienced tech. to diagnose the circuit by using more sophisticated equipment. I hope the above information will help.
I had two of au 517,I am planning to restoran all of them,do you think what should I do to have a good restoration.what should I remove and change.
The issues with AU-517 I had before were:
(1) Defective fusing resistors in poweramp caused the high DC offset (speaker relay won't kick in).
(2) Leaked pre-amp's phono input stage differential dual transistors (caused the pop noise when play phono) - see my other video.
I suggest re-cap the whole pre-amp's, power amp's and power supply's PCB. Also replacing the parts I listed above. If you can upgrade the transistors and install new zener diodes will be a big plus too.
Recently, I found one AU 517 at local Goodwill store. There are no issues for the amp. Can you recommend what area that I should check to prevent future malfunction ? When you adjust the bias, do you connect a dummy load at the output or leave it open ?
Base on my experiences, the following area needs attention are (1) Power supply regulator transistors include: TR01/02 (2SD438) and TR03/04 (2SB560) in PCB F-2675 (power supply), (2) Differential transistors include TR01/02/05/06 (2SA906) in PCB F-2723 (phono amp) and (3) Dual FET 01 (2SK97) in PCB F-2721/F-2722 (power amp). It probably should connect a dummy load at output to adjust bias but I usually leave it open. I will suggest to follow MFR's service manual if it said so.
Dual mono?
Yes, Dual transformers and power supplies.
@@VintageAudioFan wow impressive. I could pick one up in excellent condition for 500 CAD. Still contemplating it.
@@fhaquuu you should. I paid mine 850$ cad.