Sansui 7070 Receiver Restoration

[@wastelandwanderer3883]

I always found it satisfying turning a tuning dial that had a smouth operation with a lot of inertia behind it, great feeling! Makes me want to find myself an old good quality receiver from the 70's 😎

[@12voltvids]

The 70's stuff wasn't really that good you know.

[@claudiovincenzi1131]

@@12voltvids ooooohhh yes, they really were and are sooo great compared with modern appliances

[@12voltvids]

@@claudiovincenzi1131 Not really. I have a 9090 which is several steps above this one and my modern Chinese tube amp sounds many magnitudes better. These old amplifiers were not that good in the distortion department. My Technics suv9 will blow this one off the planet.

[@danielmoore7342]

@@12voltvids REALLY? We have a couple Technics SUV9's in the shop! Will be happy to send you one straight-up for that 9090 (is it the db or non-db?). It's ironic because we used an SUV9 to replace an 8080 Sansui because we needed a MC preamp hookup for a special Thorens table that had a Grace tonearm and SoundSmith MC cartridge installed. The Sansui supported MM only. While we loved the table we all kinda hated the amp and celebrated the return of the Sansui when Peter Lederman shipped his MC preamp to put between the table and the Sansui. MUCH sweeter sound. The Technics was very sterile, kinda lifeless. Let me know, we'd love another 9090! As far as that offshore tube amp: open her up and look for any solid state components and check the plate voltages on the tubes. We're getting TONS of that gear in the shop where we find the tubes are all just for show; the output transistors with their hidden heat sinks inside are doing the actual work. The tubes are basically night lights. Now after being found out China is shipping them as "hybrids" - still the same junk.

[@12voltvids]

@@danielmoore7342 my yaqin is full tube amp. No transistors in that sucker. There are many cheap hybrids out there where the tubes are just bufffer. I got my v9 for free just like the 9090. I have been offered plenty for the 9090. Could have sold it for 1500 last year. You want a great sounding amp look at pro gear. My crest v900 blows them all away. 450 watts per channel really drives speakers well and it is so clean. The 9090 sounds like garbage compared to it.

[@johnakaoldguy3158]

A work of art. I have one I bought in 1976 on a USAF Base Exchange in England. I love it and will never part with it.

[@12voltvids]

They are nice. I have a 9090 and a Technics sa700 which is another beautiful wood receiver. I haven't shown that one off yet but will service it soon

[@terrynorthern38]

I have a 7070 of which belonged to my brother, he passed at a young age, while visiting my parents years ago, they were going to trash it. Still in factory box , a great unit use it daily, miss him get solice using his receiver.

[@TheCymbalProject]

Recently had both of my 7070's fully serviced (one for the studio and one for the living room). So happy I didn't sell them!!

[@steveoszman8746]

Such a sweet receiver Sansui made them right back then. The radio reception with Sansui is most excellent.

[@bigalsmallengines]

I think Sansui made some great sounding amplifiers. Fairly well built also. Great unit! Cheers! 🍻 -Al

[@craigm.9070]

Thank you for posting this video! This line of receivers were such sweet sounding and underrated units for power. Just a little tune-up and checkout to get her dialed in and ready for some music in its second life.

[@torsteinnordstrand170]

Thanks for all of your videos. I am currently teaching myself to fix and restore old cassette players in particular, and although I don't understand half of what you do, it's slowly embedding into my brain. Keep it up!

[@thomaseddie9450]

I have learnt so much from this video, thank you.. I have an old Sony HCD-MG510AV unit that my next door neighbor discarded and is now operating fully with belts I cut from a bicycle inner tube(using a clamped steel ruler and sharp blade for accurate width). Old stuff great, I still write music on an old Atari 1040 st.

[@sanolivo6867]

I see how you hook up the multimeter on that unit. Can I do the same thing for adjustment on a Reel to Reel tape player?

[@douginmichigan.77]

Question if I may. Bought mine new in 77 a 7070 also. Just in last couple days has started to cut on and off when playing record or cd’s. Hear a click when it happens. Any suggestions much appreciated.

[@angryshoebox]

I always wondered what those flywheel tuning mechanisms looked like. I had a Sears Audio by Fisher receiver from the late '70s with flywheel tuning and a lighted dial pointer.

[@frankreiserm.s.8039]

What does it mean to bias an amplifier? Can recently made amplifiers be balanced? What is the symptom of an amplifier if one of the large filter capacitors goes bad? Frank

[@davidwell686]

Are those "fuseable links" on the back of the board? If so, you don't replace those too? Or wait till they blow? Tks

[@marcelinopagsanjan6959]

Watching sir from Philippines.

[@zx8401ztv]

That sansui has lasted well, being out of use for so long i expected quite a few dead caps. I was wrong lol. Sansui was a quality product, i know people that loved there hi-fi.

[@12voltvids]

Back when I was in the business we didn't really like these receivers or the pioneer receivers so many intermittent problems, so many intermittent shitty transistors, akai was very bad for that and Hitachi. I threw away more of these receivers back in the '80s, people would bring them in the shop with various problems and even back then if the repair bill is going to be more than about 60 bucks they would scrap them and buy a new Sony or Technics unit. I can't remember how many 8080s and 9090s I tossed in the bin but there were several. I have a 9090 that I got for free replaced all the transistors in the output circuit and the drivers. I don't know if I told that story or not but the repair bill was going to be 200 bucks parts and labor to change the eight outputs four drivers and a bunch of resistors that were burned up and the guy wouldn't pay 200 bucks for it so it ended up becoming mine. Now I know I could sell that unit and probably get $2,000 for it because there's somebody out there dumb enough to pay that for it.

[@Johnny-ov7qe]

Is replacing the driver board costly/hard to do? Have a chance to buy a 8080DB but the driver board somehow became “loose” according to the seller. Just wondering if it’s worth picking up

[@Givea_shit]

Not worth it It cant b fix . Tech can only try to fix it temporary only

[@SeanBZA]

I also look for dual SIM and SD card as well, though the lower cost ones all do tend to have both on them. Yes to the screen protector and case, they definitely do help to reduce damage.

[@zulumax1]

Sansui 7070 production years 77-79, 60 wpc, MSRP $520. Still have my Sansui AU-7700 and I have only replaced the capacitors that have gone bad, those were around the speaker relay circuit, which was also changed with a new relay.

[@TurntableGuy]

Those orange caps are low-leakage and really should only be replaced with Nichicon UKL.

[@techno90man24]

Excellent video as always! Random question: what song is that playing at 16:32 in your video? I like the tune but my Soundhound app on my phone can't pick out who made it or the name.

[@audiovideonut9078]

Do you have to put a load on the speaker terminals while adjusting the Bias?

[@12voltvids]

Having a load would cause incorrect reading on the balance test. When you bias you are setting the idle current for the + and - outputs. Of course if one side is biased higher then the other that will cause a DC offset. Some tests you use a 8 ohm resistor across speaker terminal and others not. All depends on what the manual says.

[@quiksr20]

Just set my dc offset/idle curent and I think ill be replacing the pots in the future, this things are super touchy. Barely moving them jumps alot unless thats normal.

[@zx8401ztv]

Dave, you are still up to date in comparison to me, i still use an ancent Sony Ericson phone from 1998, it's got a tiny s.d card in it, the card is incompatable with everything. But its a tough old phone, no easy break screen and its a phone + text messages only. Smart phones have way too much junk built in, i like simplicity 😀

[@12voltvids]

Those wont work here anymore as the network has been turned off. I have one too. Used a micro memory stick. Actually I have 2 of them. One is orange metal and the other one had a real camera with a xenon flash tube!

[@zx8401ztv]

@@12voltvids Now you have supprised me, i didn't expect you to have one. Mine has the flash window next to the oblong slide back plate that covers the lense when not in use, K800i Cybershot 3.2mega pixels (oooow lol). (M2 CARD SLOT) One day they will kill the network for me, the phone will still be ok for pictures taken while im doing wiring and need a record to go back to.

[@12voltvids]

@@zx8401ztv i think mine is the k800 as well. Black chocolate bar size with a plastic cover that covers the lens. I should do a video on it because people might find it interesting having a real flash tube. It's GSM only and that is being shut down here. I believe Robbers and Fido still have gsm running but not Telus or bell. They are hspa, wcdma, LTE 5g only. Never had gsm, as back in the 2g days were cdma.

[@zx8401ztv]

@@12voltvids Yes its just the way you described it, quite a few people have said how reliable a phone it is, i have dropped it a couple of times and no damage. Every few years it locks up and refuses to turn on, leaving the battery out for 20 mins fixes it. Its never caused any problems or corrupted the m2 card. I have a grey usb to odd phone plug, connect it to the pc and select file transfer, so i have backups. Such a simple and straight forward phone. My mate gave me his old samsung smart phone, what a mess of unwanted rubbish on screen. (i dont like to fight with crap user interfaces). Sony ericson wins hands down for simplicity.

[@12voltvids]

@@zx8401ztv it was great. I bought it outright for 400 and used it for several years. Took lots of pictures with that phone. Loved the real flash. I changed carriers and that was that as Telus never had a gsm network. I do like my Samsung phone though I basically run everything from it. I do all my email everything I rarely turn on my computer for email.

[@tomatojuice4595]

Hello 12volt, or anyone with this knowledge, I hope you are doing well. I need a bit of help. The f-2624 board that you adressed on this video is known to cause issues. If you or anyone has any insight or knowledge on this, I would highly appreciate it. I have read forums on audiokarma, and it seems that there are two versions of this board, but I am still lost. I am interested on a 7070, however, sometimes these are known to stop producing audio, with some forums saying that some components on the f-2624 are to blame. How is this fixed, or do I just swap everything on the board? Anything is appreciated. Thank you.

[@betamax1815]

Could you tell the name of the track that starts playing at 19:26? I assume it's one of those royalty free tracks.

[@12voltvids]

It is musicbakery royalty free but I will have to look it up.

[@frankj.mendelson5526]

I have the same one, recently repaired to replace some transistors. My question: Should it stay on all the time? I've read conflicting opinions. thank you!

[@12voltvids]

Well if you like we saying power.

[@obedjimenez2624]

I kept waiting for the restoration.3caps?

[@marka1986]

That is why troubleshooting is helpful. It leads you to the bad parts without having to replace everything. I've had some items that needed all caps changed but most of the time just 1 or 2 causing problems. Not against that either if you got the time and money and it's your unit you want to keep go for it.

[@goodun2974]

@@marka1986 , in my experience, a solid repair requires looking farther ahead towards replacement of the critical parts that would cause severe damage to the amplifier if they were to fail. Replacing just 3 parts is a make-it-"work" repair, but it could well fail, perhaps spectacularly in 3 days, 3 weeks or 3 years. Always best to put a little more time and effort into it now rather than major time and money later, or ultimately condemning it as a doorstop because it blows up.

[@marka1986]

@@goodun2974 good point, however most failures I've come across have a marginal transistor I missed in power amp. Works fine of course till they get it home.

[@12voltvids]

No money in repair. I am lucky to make 50 bucks on a unit like this. How far would you go for 50 bucks?

[@12voltvids]

Send me 300 and I will change all the caps for the owner, but the owner doesn't want to spend money on it. So where do we go. Not everyone has endless funds to spend on this old crap. I wouldn't recommend it either because I have gone down that road, replaced every cap charged accordingly and had nothing but whining and complaining because to his ear it didn't sound right.

[@rotemcohen6239]

Hi Thanks for the video! I have a question regarding the variac. In my country (230v) if i will operate a receiver on 110v it will damaged. So how is it different from working with a variac? When you feeding the receiver from 0 to full voltage gradually without damage anything? Thanks

[@12voltvids]

Running in low voltage won't damage. Many CRT sets won't start up till you get to a certain voltage. Many smps also won't start if you run up from 0 bye linear supplies on amplifiers don't care.

[@Steeleroneify]

Your stereo microphone seems to be cutting from right to left channel. I’ve been noticing it for some time now. Maybe you’re using a stationary mic so when you are moving- you dominate the side that you are talking from?

[@12voltvids]

The mic is on the camera. If I move from one side to the other the sound follows. It is usually directly above my head and then I am in the center. Thus camera has more stereo seperation than my older camera.

[@ErdosainNueve]

I'm trying to fix a Sansui ms880. But can't find the diagram... Somebody knows where i can find? Thanks!

[@HoneyWindbutton]

Dang. Was hoping to see you replace the bulbs

[@12voltvids]

Don't have any.

[@midnightrider1178]

This is a very good Receiver i have one :)

[@marcchaffee7751]

me too .

[@GustoTheGamer]

Wou did you not first test the speakers output on Voltage? You can damage your speakers. Great video 👍

[@12voltvids]

It would have to be serious voltage to damage speakers. Remember when testing for balance it is done open circuit. Puting the speakers on this would null it out.

[@robertdavis5714]

Wish you would have zoomed-in on that screw you turned to adjust FM alignment.

[@b.powell3480]

Great video, Dave, on the dim bulb tester, you can no longer buy incandescent light bulbs anywhere, they are illegal in the United States!! I was lucky enough to have a 100 watt light bulb from an old lamp. Now only ones that are available are LED's !

[@marka1986]

In the US still can find some places yet. The small grocery store still has them. In fact I can't even buy LED bulbs there. Don't forget appliance bulbs. They are 40 watts each. You can parallel them. (Put the bulbs in parallel and that in series with the line). Also look online for traffic light bulbs. They cost a premium but are long life, and you won't be going through alot of them.

[@12voltvids]

You can buy speciality bulbs. Edison type incandescent. I have a few Edison type here. 2 out over my patio and one in a lamp that illuminates my stereo cabinet. Just the right amount of light.

[@billmcdonald2436]

I found some on Amazon

[@angryshoebox]

12:20 Sounded like The Clash's version of "I Fought The Law".

[@allencrider]

I got a Google Pixel 5a phone this fall and it also was made in Vietnam. No SD slot but it does have a 3.5mm audio jack.

[@12voltvids]

Could care less about 3.5mm jack. Sd is a deal breaker. If i got a phone without an SD i would return it.

[@JasonHalversonjaydog]

Sansui was the brand of the first dual cassette deck i bought when i built my stereo system. before that i'd just had all in one stereos. that and a Sony 5 disc cd player and Sony reciever. I should've bought the Sony cassette deck too so it all matched! LOL

[@SDsailor7]

I like Sansui receivers i have two, the Seven and a 5500

[@danielmoore7342]

OK, we have a stereo shop and you have to admit a LOT of this video is kinda "different". We've been passing the URL around. So I HAVE to ask: do you always adjust the bias BEFORE you start changing out the old resistors and caps? Even before you pull the driver board? For years here we've always changed out all the caps & resistors THEN bias the amp. We all laugh a lot when we see your video! Have we been doing it wrong all these years?? Who knew? We also give you an award for most skill at trying to avoid replacing 40+ year old caps that we all automatically replace without question. We wish we could do that too (without getting fired if the boss found out). Of course, at the end you did replace a few of them anyway despite all the hemming and hawing about how they were somehow "within spec" despite misreading their values while reading your ESR meter's spec chart. I wouldn't worry, anyway. Any Sansui that wasn't filled with dust, crud and cobwebs inside like every single one we've had to service never got used much to begin with. In use the fan seems to draw in all kinds of yuk. We waste tons of time cleaning them out before we can even begin. Anyone with vintage Sansui gear like this who wants to trade for the mass market stuff of today should let me know. We'd be happy to help you. Many consider that particular series of their receivers some of the finest ever made in that price range. And anyone that has a big heavy old Sansui in the attic that has something like BA-2000 (or - be still my heart - 5000?) on it and doesn't even (gasp!) HAVE a tuner: we'd really love to help YOU out.

[@12voltvids]

No customers authorize full cap replacements. All of mine want a cheap repair so they can flog it on eBay. I did a full cap replace for a fella about 10 years ago and ended up putting all the old ones back in because he hated the sound of the new caps. Sounded fine to me but the owner did not like the sound. Good thing i gave him the old ones back. Anyway he paid me another 100 to put the old ones back in. New caps, even though they were the same value are different chemistry and had a different sound that the owner didn't like. He supplied the parts in a cap kit he ordered. This was done just before i started making these videos. I charged him 100 to change them and another 100 to put the old ones back in. Yes there was a noticable change in the sound. Both sounded good but he was used to the sound and SID NOT LIKE the brighter sound of the new ones. He liked the spongy sound of the originals. Since then i stopped recommending replacing them all. Most caps in a conventional amp will never fail. Only key caps generally on the power supply will fail.

[@alanarmstrong2323]

Nice 4 gang tuner !

[@callawayken650]

Thanks for the video.

[@albertmorris4889]

My take on dropping SD card slot Is Google (every Samsung I have had has Android backstopped by a Google account) and them wanting you to use their cloud storage (even to the point I had to take actions to prevent mine from automatically uploading to it) so they can start billing you monthly for it. Good preventive maintenance/tune up video . If parts were blown it would be a repair and if you returned it to like new out of the box condition it would be a restoration..

[@12voltvids]

Well there is a limit on what is done when there is price cap. In this case it is 50.00 parts and labor. How much would you do for 50 bucks. At work we charge 150 to run in an extra Ethernet outlet. I make nothing on this stuff.

[@12voltvids]

Never had a cloud account never will. Send a message to Samsung by not buying their latest phone with no SD. Buy other brands. They will get the message and bring it back if enough people write in and state why they bought a different brand.

[@morse.500thomas6]

Nice sansui 7070

[@petervalentimribeiro5465]

Nice 👏👏👏

[@frankmccann29]

Got one. Thanks.

[@amthanh.]

I need you help

[@nikodemoka6585]

22:46 it says 420 on his watch

[@12voltvids]

You know what. It says that twice a day every day lol.

[@FURDOG1961]

48:00

[@ThejasonJaw5442]

Samsung S20 great phone 📱

[@rogertyler3237]

When I Got My Samsung S21Ef It Didnt Have A SD Memory Card Slot. That's Only One Thing I Dont Like About It. Cause It'll Only Suport The MP3 Player App But Not The V7 Music Player App. Most Of The New Phones Don't Have The SD Card Slot. & That Sucks Cause It Dont Suport Most Offline Music Apps Except The MP3 Player App. They Want You To Use Utube Music Wich I Wont Do Cause Utube Music Dont Have What I'm Looking For & Besides Listening To Music Online Burns Up My Data. That's Why I Listen To My Music Offline.

[@morse.500thomas6]

Instead of buying a new Samsung phone I had to buy last year's Samsung note 20 to keep the SD re memory card And when this phone wears out I'll get another note 20

[@12voltvids]

Note is far too big. I got this s20fe and it is a little on the large side for me.

[@markhod1960]

I don,t trust that sony bond on the blue caps

[@jcurnutte2007]

I just got a Moto stylus 5G

[@12voltvids]

Ya mine is a 5g as well but i won't be even turning it on for awhile.