Sansui G9000 new to me,...lights up but no sound

[Wretch0501]

Thanks for letting me in the group,...as the title states, I just acquired a Sansui G9000 stereo receiver that is in very good shape cosmetically but, after turning on the power switch, the unit lights up and will switch function lights when turning from am, to fm, to phono 1-2, and aux but, the power meters don't indicate that any power is moving through the system although in FM mode, the signal strength and tuning meter function...just no sound. Any ideas of where I should start troubleshooting? Thx

 

[Script]

With quite old Sansui gear (same with Sony in my experience), their rotaries and toggle switches are prone to failure (disconnectivity). They often flip more than one connection. -So I'd definitely check them all for connectivity in power-off state.

Also, is there a relay on the audio output?

Not really much experience with old hifi and radio gear. So other than the above, you sure will need schematics.

 

[Wretch0501]

Thank you for your help,...I have never worked on any electronics before but, had a guy in Lawrence Kansas (Richards Music) that had replaced a couple of Amplifier packs) on an old Optonica receiver, and cleaned the unit but, he said that he can't get the parts (transistors) to work on my Sansui G9000, so I don't know who to consult or even have work on my unit in the Kansas City area. Any ideas? Thanks again.

 

[Wretch0501]

Thank you for your help,...I have never worked on any electronics before but, had a guy in Lawrence Kansas (Richards Music) that had replaced a couple of Amplifier packs) on an old Optonica receiver, and cleaned the unit but, he said that he can't get the parts (transistors) to work on my Sansui G9000, so I don't know who to consult or even have work on my unit in the Kansas City area. Any ideas? Thanks again.

Also, I've seen some schematics on eBay for sale, and even a guy from Texas that will refresh G9000's for $680 + $80 for shipping. But if I can find someone a little closer that I can physically bring the unit to, I would be more comfortable with that. Anyway, Thanx again.

 

[Script]

Your friend might be right about the transistors being difficult to come by. Anyway, here's the schematics.

Good luck.

 

[Wretch0501]

Thank you sir for the schematics, and your help

 

[Wiktoramps]

Hi there, long time vintage hifi technician here with my two cents. Is there a click when you turn it on, usually after about 10-15 seconds? If not then the protection circuit is being triggered which could be easy or hard. If you’ve never worked on this kind of stuff and don’t have a test bench then you’ll be shooting blind and possibly do more damage than good. With the value of these units being quite substantial your best bet is finding someone local (relatively speaking) to do the work. I’ve seen those eBay ads and can’t speak for the quality of work but as someone in the business I would never promote my work in such a fashion. Happy to give pointers for basic troubleshooting but these are not easy to work on even if you know what you’re doing.

 

[Wretch0501]

Thanks for chiming in and helping me to troubleshoot this receiver. As to your question about a click after 10-15 seconds...when I flip the power switch to on, the red protection light blinks for about 5 seconds, then the green power light comes on.

 

[Wiktoramps]

That’s actually a good thing. First with the unit off excersize all the controls and switches especially the input selector and tape monitor switches. Also look on the back of the unit, there may (been a while since I’ve worked on this model) a pre-amp power amp link switch and/or rca jacks (4 total) that are the pre amp out power in tie ins. Best to use short rca patch cables here but for proving the unit works you can use any rca cables that are known good. Do this all unpowered, then when you’re done and hooked up to speakers and power turn it on with the volume all the way off at first. You can try a line in or the fm tuner input and see if you get sound. If you do but it’s inconsistent then it just needs a good cleaning and basic service and no unobtanium stuff to replace. Also make sure your speakers are good, don’t plug it into old drivers with rubbing voice coils and disintegrated surrounds.

 

[Wretch0501]

So I use rca cables to hook from pre amp out- to power amp in?

 

[Script]

Not sure but maybe read page 42 of attached User Manual. There are hifi units that need the preamp to be connected to the power amp on the back via a cable or thick wire hook into the respective RCA jacks.

But don't listen to me -- lsten to Wiktoramps.

 

[Wiktoramps]

Yes any standard rca cables will do the trick

 

[Wretch0501]

I attached the RCA cables from pre-out to power amp in but, still no sound. The VU power meters don't register anything either

 

[Wiktoramps]

Have you selected the speaker set you’re plugged into on the face of the unit? Also if you have another power amp around you can go from the preamp out into that to see if you get sound, conversely you can plug a source (like your phone) into the power amp input. Huge warning, make all those connections first before applying power and like before start with your phone volume completely down, and only slowly go up. This can at least help isolate where you’re losing your audio. Troubleshooting old analog audio gear is a logic game so being methodical is key.

 

[Wretch0501]

Thanks for working with me on troubleshooting this receiver...I really would like to enjoy this high quality stereo

 

[Wretch0501]

Because I am on a fixed income, and don't have very many financial resources available, what would a fair price be to offer it for sale as parts? Thanks

 

[Disco Volante]

Since it's not registering any fault, I'd suspect the two relays on the F-2809 Power supply and protection board, page 18 in the manual. You might be able to carefully pry off the plastic covers and clean the contacts, depending on what type of relay is actually in there...
That should give you a hint. From there, it's multimeter, solder pen and logic. As a boy, I fixed lots of old hifi-machinery with a bare minimum of tools, patience and deduction.
But I guess with no previous experience, it's a bit of learning curve, plus a small investment...

It does look like one of those top-end recievers from the late 70's. Nice find.

Happy Tinkering
Viggo

 

[Wretch0501]

Thanks for your guidance. I ended up selling the stereo to someone who has a lot greater knowledge, and patience than I do. But again, thank you all in this forum for your help.

 

[Script]

/8=
But fair enough. DIY is not everyone's darling. Hope you got a good price.