Sansui 5000A score

[kotofei]

Greetings everyone,

I am not the member of this group yet but probably should join since I got another piece Sansui gear in my collection (the first is XR-Q11 TT). It’s Sansui 5000A receiver.

I spotted her a week ago on CL; seller mentioned in the ad that the 5000A is not working properly and if it would not be sold, it will be used as a target at a shooting range. This forced me to set up the rescue expedition ASAP. The 5000A was surprisingly well-preserved for the early seventies piece of gear and came with the original owners and service manuals.

I connected it to some suicide speakers, tuned on FM Stereo and was pleasantly surprised by the sound. No cracking or other audible distortions; meter lamps were on and off but it’s probably a bad contact. That was the only wrong thing I've noticed. I will do more tests but looks like she is in good condition.

The only thing that bothers me is that the heat sinks at the left side are protruding more that those at the right (see picture). Should it be like this?

I already read a lot about these 1040 boards that should be modified. In addition, a recap will be needed. What is the part number and source of the diodes that should be replaced, since the NTE 605a are unobtanium?

Another question, where I can get a wiring diagram i.e. schematics? The envelope beneath the wood case in my 5000A is empty and I cannot locate it at the Web.

Thanks!

 

[Robisme]

Very nice.

The heat sink should not be like that. Probably not a problem.
Pull the case and check it out.

Rob

 

[vinylisfinal]

very nice! i have the big brother and little sister to that unit... 5500 and 1000x respectively.

 

[goat67]

Greetings everyone,

I am not the member of this group yet but probably should join since I got another piece Sansui gear in my collection (the first is XR-Q11 TT). It’s Sansui 5000A receiver.

I spotted her a week ago on CL; seller mentioned in the ad that the 5000A is not working properly and if it would not be sold, it will be used as a target at a shooting range. This forced me to set up the rescue expedition ASAP. The 5000A was surprisingly well-preserved for the early seventies piece of gear and came with the original owners and service manuals.

I connected it to some suicide speakers, tuned on FM Stereo and was pleasantly surprised by the sound. No cracking or other audible distortions; meter lamps were on and off but it’s probably a bad contact. That was the only wrong thing I've noticed. I will do more tests but looks like she is in good condition.

The only thing that bothers me is that the heat sinks at the left side are protruding more that those at the right (see picture). Should it be like this?

I already read a lot about these 1040 boards that should be modified. In addition, a recap will be needed. What is the part number and source of the diodes that should be replaced, since the NTE 605a are unobtanium?

Another question, where I can get a wiring diagram i.e. schematics? The envelope beneath the wood case in my 5000A is empty and I cannot locate it at the Web.

Thanks!

Nice find.
First thing you need to do is to open it up and verify what boards you have it may have been modified already.

About the heat sink this is no biggie just how it was secured makes we think it may have been modified.

If it has not been modified I would find the new style boards as I could not find the parts needed as specified in the sticky,
and as far as I am concerned that sticky is worthless now.

HIFI Engine has a Service Manual for the 5000X it is very similar.
You can buy the 5000A version but I am not sure you need to if you are not repairing the unit.

If you are going to do a recap you will need to visually compare the schematic to the parts and make your list.

Search this forum for posts from me about this unit plenty of info there.

Oh ya do the normal Deoxit routine.

 

[Eagle1]

The heatsink fins on the one side are bent which shouldn't cause any problems as long as the base is still straight or no internal damage. Also it looks like the AM antenna is shorter than normal. Bent fins and broken antenna could mean it was dropped or damaged in a shipment so check the insides for indications of damage. Good time to clean out the dust and crap while it's open and check all of the bulbs and verify your driver boards.

 

[kotofei]

Opened her up today. The first look was at the preamp boards and ... instead of the dreadful 1040s I saw a pair of F-6013. YES! They were changed before; even their PCB color looks different.

This is the real present for the New Year.

The fact that driver boards were replaced might explain why some heatsinks protrude more that others. The heatsinks are secured with screws and few of them were half-loose. I did not see any bent fins.

The 5000A looks very clean inside, surprisingly small amount of dust for the 40-year old unit. It still had two spare lamps which were handy since the meter lamp and another one required replacement.

Eagle1, I don’t know how long the AM antenna should be. I made a close-up picture; apparently, something was unscrewed from its left end. However, I did not see any signs of damage caused by potential dropping of the unit.

I will give the 5000A a bath of Deoxit. Now the question is- what is the procedure for bias adjustment if I have the F-6013 boards? I clearly see 2 pots per board.

Another question- any noisy transistors which are recommended to be replaced?

Many Thanks,

 

[markallen]

Opened her up today. The first look was at the preamp boards and ... instead of the dreadful 1040s I saw a pair of F-6013. YES! They were changed before; even their PCB color looks different.

This is the real present for the New Year.

You are incredibly fortunate to get the upgraded boards!:thmbsp:

I have two 5000A's (both in excellent physical condition - INCLUDING the wood cases!) and both are factory original. Can't get either the NTE 605A or the STV-2H diodes to retrofit them, at least not without spending a small fortune. Supply and demand, etc. So they remain on the project shelf.

 

[Eagle1]

Eagle1, I don’t know how long the AM antenna should be. I made a close-up picture; apparently, something was unscrewed from its left end. However, I did not see any signs of damage caused by potential dropping of the unit.

The AM antenna should be 7 1/2" long with about 1 3/4" proturbing from the left side looking from the front. I can see from your pics where the antenna was originally mounted and it has been moved. If you're not a big AM listener no big deal other than it's no longer original. But does prove that it was dropped or suffered some external damage along with the bent heatsink fins. The original owner did a nice job in cleaning up the antenna breakage but the scarring from the mounting bracket is the sure sign it's been modified. Glad to hear you have the 6013 boards as the sticky for the 1040 board upgrade is incomplete. The SM available at HiFi Engine for the 5000X is for the early release so it should work just fine for the 5000A. The telltale is in the tuner pulley and stringing design. My early X is very similar to the A model. I haven't recapped mine yet but does sound damn good and can power any one of my speakers in my arsenal. It is a very sweet sounding receiver with more power than it's rated at. Very strong tuner section and if your into LP's a great phono interface. I have a recap list if you need it ala Goat67 but as always check your orginal values before ordering. Enjoy and don't let out the magic smoke.

 

[kotofei]

Thanks Eagle1,

I am not AM listener at all so the AM antenna stuff doesn't matter.

If I understand you correctly, the 5000X has F-6013 boards and so its service manual has the procedure for adjusting the bias on these F-6013s? I have a service manual for this Sansui but it lists the procedure for 1040s.

Yes I would love to get your re-cap list since I have an idea to keep this Sansui for the second system-in-planning. She will probably be matched with the TT so phono stage quality is important.

Thanks a lot.

 

[kotofei]

You are incredibly fortunate to get the upgraded boards!:thmbsp:

I have two 5000A's (both in excellent physical condition - INCLUDING the wood cases!) and both are factory original. Can't get either the NTE 605A or the STV-2H diodes to retrofit them, at least not without spending a small fortune. Supply and demand, etc. So they remain on the project shelf.

Someone on Epay as of yesterday had two F-6013 boards for approx. $85 with free shipping.

 

[Eagle1]

Thanks Eagle1,
If I understand you correctly, the 5000X has F-6013 boards and so its service manual has the procedure for adjusting the bias on these F-6013s? I have a service manual for this Sansui but it lists the procedure for 1040s..

The early release of the 5000X had the 1040 driver boards, luckily mine had been upgraded either at the factory or by a qualified Sansui shop during the recall. I'm not sure if the 1040 and 6013 boards are the same in regards to the adjusment settings. I know that Goat67 has a supplement and simple procedure for adjusting to spec. He did it both on his 5000A and X and mine, just don't remember the values, nor does he. I'll see if I can jog his memory a bit.

Yes I would love to get your re-cap list since I have an idea to keep this Sansui for the second system-in-planning. She will probably be matched with the TT so phono stage quality is important.
Thanks a lot.

I've attached the recap list, Mouser would be your best bet for them. It does not include the main filter caps (cans). But yours don't show any signs of leakage yet. I believe Percy has them at the right size but at higher values with the solder leads which should be okay. Stay away from the snap-ins if you can, bitch to solder all of the wires to. Yes the 5000 series is a keeper and much more with the all wood case. Buy some Howards Feed-n-Wax for it and apply it with a clean cloth. It really brings out the wood features. The case will absorb it like a sponge and make it look great and keep it from splitting.

 

[kotofei]

Many thanks Eagle1,

I will ask around for the 6013 board adjustments or will get an appropriate service manual somewhere.

Keep you posted.

 

[goat67]

Here is your Bias adjustment info
http://www.audiokarma.org/forums/showthread.php?t=230524
It is in the last post

 

[Eagle1]

Here is your Bias adjustment info
http://www.audiokarma.org/forums/showthread.php?t=230524
It is in the last post

:thmbsp:

 

[kotofei]

Here is your Bias adjustment info
http://www.audiokarma.org/forums/showthread.php?t=230524
It is in the last post

Thanks goat67,

I looked at the last post in the link you provided and did not understand anything. Here is what you wrote in that post:

Check the Bias first.

Then the output voltage 80v. Measure these voltages between ground and c005 positive and then ground and c006 positive pin these are connected to the collectors of the output transistors
If you need clarification let me know

Also as far as easier things to check you can check the output transistors that are mounted to the heat sinks for the left side.

Remove them and then check them out.

As I said if I was to do this I would recap both driver boards as IIRC both may need to be removed you will see when you try to unsolder the ground leads.
If you take the boards out then check the transistors on the boards.

I attached some helpful info for you

What exactly should be the bias that should be first checked? If it required adjustment, which of the two pots at the F-6013 board should be used?

Then the output voltage should be checked and it should be 80V, right? Shoudl it be checked at the same settings as bias (i.e. main control volume to the minimum etc)?

The c005 an dc006 caps are 2200microF large electrolytic caps near heat sink, in the power supply. Is this correct? I don't see any c005 and c006 on the F-6013 schematics or elsewhere.

Then, what should be done if the output voltage is NOT 80 volts? How to adjust it?

Sorry for so many questions.

Thanks

 

[goat67]

Did you look at the attached files in the post?
The second one provides detailed step by step instructions.

If so and you do not understand what it is saying to do I do not know if you should proceed as you could make matters worse.

The only thing I do differently is I do not adjust the pots fully CCW when the unit has not been worked on.

Bias is 20mv measured by removing the fuse and using an Amp meter in line
Adjust VR802 on each board

You can measure Vcc from the fuse and ground say it is 80.00v then adjust for 40v

Output voltage VR801 adjust for one half of VCC again follow instructions in attachment

Yes You have the caps correctly identified they are the output caps and it is the same electrical connection as the test point specified in the instructions

Thanks goat67,

I looked at the last post in the link you provided and did not understand anything. Here is what you wrote in that post:



What exactly should be the bias that should be first checked? If it required adjustment, which of the two pots at the F-6013 board should be used?
20mv +- 3mv
VR802

Then the output voltage should be checked and it should be 80V, right? Shoudl it be checked at the same settings as bias (i.e. main control volume to the minimum etc)?
Yes

The c005 an dc006 caps are 2200microF large electrolytic caps near heat sink, in the power supply. Is this correct? I don't see any c005 and c006 on the F-6013 schematics or elsewhere.
Yes you got it

Then, what should be done if the output voltage is NOT 80 volts? How to adjust it?
VR801
Sorry for so many questions.

Thanks

 

[kotofei]

Oops!

I did not realize that there are two files attached to that post; the second thumbnail is tall and close to the first one and I thought it's only one file there. So I looked at the first only and missed the second with detailed instructions.

That second file makes everything clear and answers all the questions.

My sincerest apologies, goat 67.

I think that file with instructions of yours or thread should be made sticky since there are of general interest.

Thanks again.

 

[goat67]

No need to apologize
Have fun.
Be sure you have you meter set to measure Amps / ma and make sure the leads are in the correct place on the meter when adjusting the bias.

If you are not sure post a picture of you meter.