Great video. I've worked on a lot of equipment from that era and always thought the Sansui gear was better made than most, well laid out and easy to work on, kenwood was another company whose gear was better made than most. I bought the 2000 when I was serving in Korea in 1969. We were on a remote mountaintop microwave site and we repaired the microwave systems to keep communications up and working. My receiver lost one channel during a thunderstorm so i took it apart and did some troubleshooting. i found one fuse and output transistor blown, this was still in warranty but I had no easy way to get it down the mountain and up to Seoul where the repair depot was. I wrote Sansui in Japan and explained how the unit failed and told them I wanted to buy a set of transistors and a schematic and would send them a check as soon as i knew the amount to send. A little over a week later I got a box in the mail with the parts and a service manual. They sent a note with a technicians phone number in japan I could call if I needed any help, they said the parts were supplied under warranty so no payment was required. i replaced the bad transistor and it's driver and the unit worked fine. I wrote back to Sansui and thanked them for their help and told everyone I knew what a great company they were to work with.
My brother in law bought an outrageous Sansui quadraphonic receiver during Vietnam and the thing still works perfectly and sounds great, really cool playing old quad vinyl and tapes.
What a beautiful piece! Glad the owner has taken such good care of it over the years. Suspect those ornery little transistors will continue to cause problems in the future though. ;)
I have a 4000 among numerous other vintage amps and it is by far my favorite looking and sounding amplifier. I use it everyday for hours on end. Once again, I learned a lot from watching how you diagnosed and rectified the fault. Looking forward to more videos. 👏👍👊
Thanks for your time breaking down your troubleshooting and repair of this gem. Not very many in this condition out in the wild anymore. The owner is likely very happy his receiver is reconditioned for its next phase of life, that phono stage should sound sweet.
I have and use a 2000x receiver. Most everything is fine on it but it has noise, which is most likely all the 458s in there, broken balance control, and all the panel lights out. I have a box that has all the parts for the receiver. I am going to refurb the receiver as a project in the next few months. According to the serial number, my receiver was made in late 1969. Thank for the fantastic video.
These are from the good 😌 old days. I understand that the capacitors need changed by now, but these were a GREAT 👍 radio. My dad had something like 👍 this, back in 1976, or 1977. It was on a shelf in the living room of our mobile home 🏠. Lum and Abner was one ☝️ program we used to listen 👂 to. The baseball ⚾️ game sounded so great 😄 on it. So did the news 🗞, and music 🎼. Although the stereo was solid state, it did a good 😌 job. It had the same green lighted dial. I’m pretty 😍 sure it also had an 8-track, and record player. Although cassette tapes were around then (and the late 1960’s), a cassette player wasn’t featured on this stereo. Please keep these GREAT 😊 stereo videos coming!! Your friend, Jeff.
When I was young, the Sansui Eight Deluxe caught my eyes. But I could not afford it only dream about it. Time flew. Love watching all those vintage stereo brought back to its glory days.
Those Sansuis were truly well put together. I am currently working on a predecessor, the type 250 with tubes. Bit of a rats nest without the PCBs but chugging along replacing caps and a few wayward resistors. Amazingly the tubes all test good..
Thanks for the Video. Enjoy watching them every time. My brother brought a Sansui 2000 back from Vietnam in 1969. It’s been in storage for years. My brother says he knows where but not likely. Hope you can fix it when the time comes. Your neighbor, Rex
Great repair , repaired allot of audio in 55 years , all manufactures inc video etc. Old car radios fun and consoles also all the tape deck's , reel to reels tascam etc. Srarted with tube stuff first then all the way to modern yamaha, harman, JVC etc. commercial and consumer. Retired now Just working on Teensy, arm, risk 5, PI, Pi pico some with wifi and Audio synth Ic's fun for me. Keep up the great repairs, reminders for me esp tuning IF's etc. I used sencore sweep generator also a heathkit in past. Favor-et cap checker the Sencor model LC73 z meter.
I had a 2000 that used miniature screw-thread lamps that had corroded to their sockets, an absolute PIA to get them out. The AM tuner performance on that particular Sansui was phenomenal. I could do impressive DXing at night, from inside a room with a chicken wire & stucco exterior wall using just the fold-out AM antenna.
Thanks for the tip on the crossover distortion. I've been rebuilding a few of those notorious 1040 boards; a couple with new drivers. Will def scrutinize the wave forms now.
Beauty! Using a saw tooth signal makes it easier to reveal cross over distortion and clipping. I did not see any 8 ohm load resistor when you did the power test.. but I trust it was there. I always adjust DC with regards to zero signal. Basically I want no DC in normal working mode, and I really don't care about uneven clipping at max output because it will never operate there with speakers connected.
I have an Sansui 800 from this same line. And I have discovered a strange problem where I get loud crackles when humidity is high. I live in Florida and this week we had windows installed so I had my AC off for 2 days and sure enough it crackled for a day. But I lowered my AC a few degrees and after day 3 it’s working great again. Recently had it serviced and the bias was adjusted. I think it has the problematic transistors in the output boards that I should replace but as long as I have my AC on it sounds incredible.
@@thechuckster1971 here in San Diego thats called beach disease. Humidity and minerals cause deposit buildup on small signal path transistors. Right where the leads enter the body. Combine this with humidity and little leakage paths develop. This needs serious troubleshooting. Don't just start replacing parts
@@JordanPier thank you for replying. Im in a weird spot with this one. Is it worth the cost of having some one trouble shoot and repair? I can probably find a serviced unit for less than the cost of having mine gone through. I am probably just going to enjoy it unless it starts acting up while it’s in my air conditioned space.
Sansui's have a lot of silk screen errors on their boards, many electrolytic capacitors will have the + printed on the wrong side on the board. I tried the across the rail fuse method for setting the bias on my Sansui AU-7700, however I powered it down and forgot about the inrush current to charge the capacitors, blew the cheap $7 Harbor Freight meter. Oooops! Got those because I like monitoring both channels, and they are cheap in case something like this happens. There is a second way in the service manual with requires unsoldering the red wire to the output board and hooking the meter there, that way the inrush current bypasses the meter.
Ha! When I was 13, I took a wad of paper money saved from my paper route, and bought a Zenith Allegro shelf unit w/ LP, AM/FM stereo. Had this exact problem. Took it back to the store & got another.
I had a 2000A model, not sure what the difference is with the 2000X. Single push pull outputs generally sound warmer and more involving in my experience. A for American perhaps since this one was probably overseas model is my guess. Multi voltage capable most likely.
The hard part for me is just trying to figure out how to open it up. Mine is a 3300. Looks like there are only 4 screws in the back, and some of the knobs in front look like they have tiny screws. I don't want to do anything other than clean it and some of the push on off buttons wont stay depressed. Trying to find a video that will help me. Not sure if I should even attempt it!
Great explanation and description! I have a 197x G-2000 which exhibits the symptom on only one FM station, 89.1. All other FM stations come in fine.Is that the same issue or something different? (I can get the same station on a different band.) Thanks for your help. I appreciate it.
I've got a 1964ish Voice of Music solid state console that I rescued from the curb. Has phono and reel to reel. Got phono working and tape seems to work (no tape to actually try it but microphones feed out OK. Problem I have is neither AM or FM work. Amp output is OK. No stereo light, nothing. Dead quiet. I have the schematic. Tried checking some voltages with multimeter at points shown on diagram. Voltages are off in several places on the IF board. Suggestions as to where to look first? I don't have signal tracer or working scope. Don't want to fire the parts cannon. I assume that it has some dead electrolytics. Nothing physically obvious (no leaky, burned parts.
Since both am and fm are dead start at the power supply line that feeds the tuner. Voltages can be a little off, but usually more than 20% low and stuff stops working.
May clean my dad's up as a bday present. Family still uses as an amp even though all switches except AUX is kaput. Should also add 'as seen on Season 1 of the hit 20th Century Fox program Vega$ starring Bob Urich😊' Good for gen info as I 'get the call' for all Mom and Dad tech issues...
Interesting IF alignment. Obviously it works. I'm curious - real question - why this is better than feeding it a 10.7 sweep and adjusting the s-curve. I would have thought peaking runs the risk of ending up with the IF being too narrow. Interested in why you did it this way since it clearly worked well.
Its not necessarily a better way, just faster, and the average listener will not notice the difference. In a laboratory environment with a distortion analyzer I'm sure using a sweep/marker generator and following the service manual would yield more precise output and lower THD. The If amplifiers are only designed to do one thing, and that's amplify the 10.7mhz while rejecting as much side-band junk as possible . I'm peaking those after making sure the RF output from the tuner is the best. Then I can assume that if all stages are working, peaking the 10.7 signal will allow for the greatest amount of information for the FM detector, which is the crucial element in demodulating the music. The way these tuner circuits are designed, adjusting the primary for null and secondary for best symmetrical clipping with poor signal shows that I'm about as close to on center of the detector as I can be. If I were not able to achieve good output then I would break out a sweep and look at the curve on a scope. Likely something in the detector circuit would be amiss assuming amplitude of the 10.7mhz was sufficient.
I have a 5,000 a that my father bought when he was over in Vietnam and it was at my grandmother's house for years after she passed I took it speakers as well and one output fuse keeps blowing on the right channel I think it has something to do with the separate output boards one board has some sort of a short in it haven't been able to find it looked at the diagram and I'm kind of new at getting into the electronic stuff heavier I'd love to figure out what's wrong with it but if I keep watching videos like this eventually I might figure it out.
If yours has the 1040 amplifier boards inside, its likely a failure of the black square bias diodes sitting atop the driver transistors. This is common. They open, and blow the output stage. There are ways to fix it, but not for the beginner. Eventually I'll do a video on how to repair them. Its worth the effort.
@@JordanPier Cool, I did do a basic short test on things I put one lead on a chassis and was touching around places and it seemed to be something of that sort on one of the output boards, like you say a little box on top of a transistor. It doesn't look like it would be an easy fix because the board is attached by a ground strap and some other stuff, I did see kits on eBay for rebuilding those boards same number board is what was on the wiring diagram inside the unit. I can tell it's never been worked on before.
Awesome video. I have a Sansui 2000x stereo receiver no power going to lights. I knew there were a few bulbs not working so I opened It up and blew it out. I plugged it in it was on aux . When I turned it to FM I saw a spark come from the wire going to the light bulb all the way to the left of the display the wire was exposed and grounded , then all the lights went out. stereo works great just no lights at all. Any ideas.
You probably blew the fuse for the lamp supply. Follow it back to the transformer. Dual lamps are not lit on those unless the radio is selected. Otherwise you should see a light of what In put you're on (aux, phono, etc)
A Newbie question. Where do you inject a signal on these vintage receivers in order to troubleshoot with an oscilloscope? Thanks, I really enjoy your videos.
Hi Jordan… I was wondering if you could help me out. I would like to use speaker channels A + B simultaneously with this setup: One pair of passive speakers to be wired in parallel to a powered subwoofer in Channel A. A second set of passive speakers connected to Channel B. My question is: will I blow my Sansui 2000x because of ohm impedance? I hope you’re able to help. I’ve been scouring the internet for information but it’s not easy to find an answer. Thank you
So long as both sets of passive speakers are 8 ohms or greater it should be fine. The amplifier input of the powered subwoofers are very high impedence - usually around 47k ohm
It's also true that if it's a 2000x, it should have a preamp out/main-in loop on the back. Using a y adapter you should be able to feed preamp level info right to the powered sub and run your passive speakers directly from the sansui without having to parallel them with subwoofer inputs.
@@JordanPier The powered sub is a Paradigm PDR8. Not much info out there as I tried to find out what it’s impedance was. But if it’s standard for subs to have that high impedance, that’s good. Thank you.
I have an issue where every input works great on both speakers but if i put it onto FM Auto on my 4000 only the right speaker has sound and the left barely any. what could be the issue?
If you press the mono button and the channels combine you've either got a failure of the output of the multiplex module that's at the right front of the machine, or on the phono preamp that serves as a preamp for the mpx output.. Either open capacitor or failed buffer output transistor. You really need a signal tracer or scope to find it. Xraytonyb has a good video on how to build a budget signal tracer. Either c428 or 429 on the mpx board is open (depending on channel), c601 or 602 on phono board is open, or one or more phono amp transistors have failed. See if both channels operate when playing a turntable through phono. If not, you've narrowed down what board the problem is on ; )
@jordanpier Hi there, xraytonyb sent me your way...i have a Sansui au717 that ive been looking to get restored/refurbished and was hoping you could help me out!? 🙏
I have this model with the same issue, would like to have repaired, wondering if you are interested and are close to me, I’m located near Pittsburgh Pa.
Thanks. I forgot about the bottom hex screws. I had a 4000 model before in just the black metal case. My 2000X is working well other than FM is weaker than it should be and Stereo light is not working. @@JordanPier
I just sat down with my 2000X and my FM tuner is actually working fairly well. It will play in stereo, but my lamp may be burned out. All of my dial bulbs were bad. I have a kit coming from ebay. I did notice my Muting Off button does nothing. It mutes on or off. Another thing is my meter will not go above about 3.5, even on a 50,000W signal 2 miles away. Is there an adjustment for just the meter? @@JordanPier
@@jbetnar don't remember if there is a meter adjustment. However the meter and muting circuit are intertwined. The fact you're muting and the meter shows a low signal may be related. the fact the tuner muted with muting "off" also points to that circuit
Hello Sir, I have a Sansui 5000A with the same problem.I get signals from fm stations but no sound comes out.Could you be kind and generous enough to tell me what you think about the problem ?Thanks. Enrique Jorge Enrique Jirge
Check the last IF Integrated circuit just before the detector. If it has failed it will yield this symptom. Use a signal tracer or scope to confirm. 3rd IF yields signal meter information, 4th fires into the detector for output. I assume you can get sound on AM/MW?
Not too tricky to figure out. 1. check for DC voltage at the amplifier output at the relay. Should be 24v for the coil and that's it. 2. If that's good, check power supplies against the schematic. Usually there is + and - 35-40 volts, 12v and +30v for the preamp. If in doubt, consult the schematic. 3. if that's good, then protection circuit itself has issues. Definitely advanced troubleshooting needed. If you want to throw some money at it, send it to me. Inbox me on how. vintageavrepair (at) gmail dot com
