I bought a 1000A. Just replaced ALL the electrolytics, oil caps and a few others. New diodes. Works and sounds great except when playing it will make random popping noises every minute or so. I tried wiggling all the switches and the control pots are cleaned but can't seem to find out whats doing it. Any suggestions?
Look for open or badly out of tolerance resistors. Bad switch contacts and pot contacts. Even an bad power switch can arc, inducing various noises.
Is the popping on one channel or both?
Is the popping on one channel or both?
A few questions
-Turn on the amp and open the vol. Without any input.. noise is still there?
-Turn on the amp and Volume at minimum...........................noise is still there؟
Turn the amplifier upside down. Open the bottom cover. Turn it on and turn up the volume a little.
Tap the insulated end of a screwdriver on different parts. Is there any sound coming from the speaker?
This is a troubleshooting method for an old hand-wired amplifier. Repeat the same with the tube sockets.
Tap the insulated end of a screwdriver on different parts. Is there any sound coming from the speaker?
This is a troubleshooting method for an old hand-wired amplifier. Repeat the same with the tube sockets.
So with no signal it doesn't do it. But when i start playing music it pops on both channels at the same time. Seems to get worse the longer it plays.
I found and fixed it. There was something on one of the 12ax7 sockets. I tapped it and it made noise so I replaced the socket and redid all the connections to it and no more noise. Thank you to all that helped. I now have a VERY nice 1000A receiver. It sounds great.
Hi jwags81818,
Excellent, but a lot of work.
Sometimes you can tighten the pin, or that pin can be removed and a new one installed. Depends on the socket. Examine the one you removed for future reference.
Glad you found it.
Excellent, but a lot of work.
Sometimes you can tighten the pin, or that pin can be removed and a new one installed. Depends on the socket. Examine the one you removed for future reference.
Glad you found it.
I am not even certain it was the socket. But I had a nice new one sitting in my parts inventory so I replaced it and the resistors connected to it. Everything has nice shiny solder joints and has been playing all morning without a single pop. After replacing 85 components this was a small job.
You did a good job. Tapping will identify the fault area. But it may not be the socket. Did you tap again after replacing the parts?
Had a similar socket failure on a 1000a a couple of years ago. I had replaced all the electrolytics and oil caps and it now belongs to another person. He had a similar noise issue and I offered to look at it. Tapping things found the location but resoldering the connections, replacing a couple of questionable components and cleaning/retensioning the socket had no effect. Finally replaced the socket and all was well. The sockets that Sansui used may have been of a prone to a long term degradation more than others.
Nope. Tube sockets are typically made in a similar fashion by most. Sansui bought from standard suppliers. Tube sockets may have common failures, and even a drop of water in one pin long ago can ruin that contact, or allow tracking between pins.
This type of failure is not uncommon at all. It happens with equipment from all over the world. Nothing unique to Sansui.
This type of failure is not uncommon at all. It happens with equipment from all over the world. Nothing unique to Sansui.
Sensui is not well made. The quality of the parts is lower than American. There is a possibility of failure everywhere. Only the output transformer. I bought three Sensui just for the output. The Sensui Transformer was great.
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I restored a PM-2020, nice quality. Working on an AU-111 and have done others. Again, nice quality. Do they have areas they could do better? Yup.
Want to see something not well made? Pioneer tube units. I'm sure there are others.
Sansui did not make the tube sockets, neither did Fisher or anyone else. The parts manufacturers made the parts, including switches and sockets, controls. I have not seen any abnormally high numbers of socket problems with Sansui, Pioneer or Fisher or anyone else.
Want to see something not well made? Pioneer tube units. I'm sure there are others.
Sansui did not make the tube sockets, neither did Fisher or anyone else. The parts manufacturers made the parts, including switches and sockets, controls. I have not seen any abnormally high numbers of socket problems with Sansui, Pioneer or Fisher or anyone else.
The problem with the sansui is poor assembly, which makes it difficult to service and repair over time. There are many failures of capacitors and resistors.but . They are excellent in sound.
I'll agree that these old sets are difficult to service. But this and other Sansui models are no worse then other contemporary sets. Eico, Fisher and many other sets are a jungle. One nasty surprise I had was the very early PM-2020 had shielded wire that was decaying and shorting intermittently. I had to replace all of it using RG-174, every single run. That was after I had it rebuilt, fun.
What is nice is that modern components are smaller as a rule, so it is neater and more open once rebuilt. I see you used radial capacitors. I always use the original axial leaded parts so the parts install in the same positions.
About the only simple construction is in a straight power amplifier. Compared to a PCB based unit, these are a nightmare to work on! Very, very time consuming.
What is nice is that modern components are smaller as a rule, so it is neater and more open once rebuilt. I see you used radial capacitors. I always use the original axial leaded parts so the parts install in the same positions.
About the only simple construction is in a straight power amplifier. Compared to a PCB based unit, these are a nightmare to work on! Very, very time consuming.