I had a 1989 technics system and receiver did same thing 10 years ago. No videos back then on how to repair so i threw away. I've always missed that receiver but yesterday i found one next to the trash dumpster....same things happening to it but with this video ill finally be able to have my technic full system back together again! Thanks.
I'm an Aussie DJ Audio/Visual engineer. When I was a kid.......I'm 57 now, I used to service all the old BW TVs and radios of the era that my friends had and amassed a huge selection of TV and radio tubes or valves as we call em here! The main problems were horizontal and vertical output tubes failing so you'd get that nice beam of light going either way with sound! I fixed them, adjusted the picture geometry and at 12 years of age I charged a dollar which was huge for the 60s and 70s. I was very careful with the high voltage rectifiers, the good old 1B3GT and often fixed the monitors at school and wired up power plugs for many things. I had stacks of 5AR4s and other tubes for radios and hifi amps and often fixed them at the amazement of other friends parents! If I couldn't fix it, I knew what was wrong and wrote down the info for the techs who always wanted to meet me which was a real buzz for a 12 year old! Like this amp I often used perfectly good second hand parts to fix a problem but my mum said that I had to do it for 50 cents to teach me the value of money. I wish I could go back to those days where people were honest and life was so much simpler! I love your channel. I should've gone to a tech school but back then it was so different than today! Cheers! Andy from OZ!
It's great!!!... Answers to all my questions for today's malfunction))))) Thanks, now I reliably know how to repair my own Technics... You have finally convinced me that I am moving in the right direction... Wholeheartedly!!! )))))))))
DUDE!! You are the BEST!!! SA-GX670 Back to life! I had the same, had to move to to make the relays kick in. I knew the second I reflowed it, and I heard the joyous sound of the second relay click I had success! I just absolutely love this receiver. It's a spare, but I also had SA-GX505 since I was in my teens and I saved up 4 paychecks to buy it. I just have such fond memories of this series, even so it's a bit obsolete by today's standards. Thanks again. Happy New Year 2020! Edit - My fan was perfect though, but I always babied mine, and kept them perfectly clean. Also, SA-Gx670 seems a bit "toasty" around DRIVER IC STB area, specifically q735,q737, r740+r743. It's normal, or should I be concerned? I havent had the hood off SA-GC505 much but dont remember anything like that, but it's also not H+ either.
Hello! Another happy customer... And a quick and classic fix. Your repair is near perfect, but you should be more attentive to dust problems, as we can hear you cough. My advise to many technician is to take care of their health and to avoid inhaling it: use a vacuum cleaner or a dust mask! I used to work as a TV tech some 30 years ago in Paris, and had a colleague who spend days at the hospital with serious intoxication. Cockroaches love dark and hot places, and he sprayed them generously with a bug killer can he always had ready at hand when he opened VCRs, TV sets. But he made the near fatal mistake to inhale the dust he removed and dispersed with a air spray, along with the insecticide. This effective product is also a permanent treatment that set a layer of microcristalline poison. (A Bayer technology I suppose used by many of brands). We found then it was safer to use first a vacuum cleaner and a paint brush to remove dust, rather to disperse dust everywhere in the shop. And the result was we had a much safer and cleaner environment. The cockroaches problem was also partially solved using a sort of fumigation and decontamination box, that was big enough to treat a TV set, open it and vacuum clean it, that was close to a nowadays sand cleaner. No definitive treatment is alas proven safe, and as far as the total environment is cleared, the bugs will always come in... Later, we did the same thing with computers, and many forced cooling systems, as the fans are accumulating much more dust and contamination. I also advised friends working with domestic appliances like microwave ovens... And the same problems! You never know if the dust you inhale from an apparatus is toxic or not: you can find fungi, bacilli, asbestos, lead... And many other dangerous contamination.
That cough was staged by the way. In reference to the gopher from Caddyshack after bill murray blew up the golf course and the gopher lived, and coughed twice as he "coughed out all the dirt he inhaled" I do it every time I use the compressor as a joke. Same as a made reference to a line from "True Lies" when my battery died on my laptop. "Battery dead... go and get another one"
Hey, I thought I'd post a comment here for anyone who has a similar problem on a Technics amp from the early nineties which isn't caused by a bad joint.on the power amp. These Technics amps drive their fans on demand when there is a high power output (only very loud with a lot of bass, etc.). On my receiver the fan would never move and the amp would cut out at high power (drum beats, guitar riffs, any sudden spike of volume). Turns out these amps are designed to shut down speaker output when the fan isn't operating as it should (funnily enough this does not trigger the "over-load" prompt on the main screen). So when you have a similar issue it's worth checking the fan motor, fan connectors and the fan supply board. On my example the solder joints connecting the fan to the supply board were completely busted. Supply board had to come out. Anyway, I thought someone might find this useful. Cheers
😅😅😅 love the ring tone...so good. Wives and electronics, like oil and water baby. Thanks for sharing your electronic experience with us. Cold solder joints and noisy fans...been there, nice that Technics put that removable panel there so you don't have to pull the whole board out. 👍👍
Wish they'd carried on with it as well, when I picked up my early 90's stack system I very nearly threw it backwards over my head, it was so lightweight! lol
I fixed SA AX610 encouraged by you- thanks!. Cracked solder joints. I didn't see them until using a magnifier. Keeps it out of the landfill. It is a good stereo.
I have an SAGX 690 and it never gave an issue, even when I had it running outdoors for a party at near max all day. It started to rain and we were on the boat. By the time I got back and it was pouring but the system was still blasting. You could see the steam emitting off the amp. This was one of the craziest things I have ever seen with electronics. Amp is still running today in my recording studio.
Good repair, enjoyed this, thanks. Just wondered if you did any explanations on surround sound on your videos? I'd like to learn a little more about things like Dolby SS, Pro Logic, DTS, all the other codecs. Thanks. Also I have a question about audio dummy loads. Can they cause power transistor failure ? I had recently bought a set of dummy loads that is for tube or transformer output it said, it reads 8 ohms. I didn't have the non inductive type as of yet. Anyway I tried it on a old transistor guitar amp, I can't find a schematic for it, but I found it didn't have an output electrolytic cap to speaker, it just goes straight to speaker. I've tried to trace the foils. I changed the old electrolytic caps. The amp is made in the 70s, I found some caps open, some leaky so I replaced them, I replaced the output transistors with new NPNs from mouser 2n3055. Everything checked out and I powered it up, checked it and the amp blew a fuse after 2 minutes of setup looking at a sine wave from my generator on my scope. I found the two new power transistors had shorted/(fused together.) Someone had told the 2n3055 cannot handle as much current as the older ones, I'm not sure of that though. Can you give a little info on the subject? It would be greatly appreciated. Thank you! :)
I appreciate you doing this - I have the "OVERLOAD" error on mine which is a Technics SA-DA15. I love the receiver but even without speakers attached it goes into the error. I wish you were nearby to fix mine. What would it cost if it were a simple fix that you did to the SA GX550? I plan to take it out of storage and see if the fan comes on as you did but without the speakers attached. I don't have any equipment like you nor am I familiar with them.
Love the way you melt tabs on the fan motor plastic to keep it on. I’ve seen you do this a couple times now, I gotta try it! Oh, the Vintage pre-amp sounded so much better thru headphones... just sayin.
I'm a tech at a car dealer and spend tons of time trying to explain how someones car works to them even though there's probably a manual with the car for the owner that might be able to explain it to them better. Probably, but they'll never know.
You may have heard that in a garage where they have a device mounted on the outlet of the compressor that infuses the air with oil so it lubricates the pneumatic devices eg impact wrench etc.
That doesn't help when both the TV and the dvd/VCR combo are the same brand. The problem in the end was they got the TV on the right input but the dvd/VCR was on the VCR mode and because there is no cable connected it was displaying "no signal" on the TV.
They use the fan as an exhaust fan to pull heat out from the unit. The reason they went to this design in the first place was because of all the idiots fire stacking their components in a cabinet with glass doors. The idea was the fan would blow the hot air out the back.
That is entire possible. The tune is called "Corporate Image" licensed by the music bakery. The composer, Jack Waldenmeier has composed over 800 tunes and jingles used in TV, Radio, Film. There is a car show on TV called Driving Television, and until this season they used musicbakery track passport as their voice over track, and Street Beat as the closing credit music. Very popular indeed. If you call Blackberry about a problem with your phone and get put on hold you will hear the track "cityscape" while on hold.
I have the same model and had exactly the same problem,did the fix to cold soldered joints but couldn't find a replacement motor.What is the size?24 mm?Also what voltage is it?
@@12voltvids Like this one?I do not have any old stuff around.www.ebay.com/itm/MABUCHI-RF-310TH-11400-DC-3V-5V-6V-24mm-Diameter-Mini-DC-Motor-for-CD-DVD-Player/262934050686?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m1438.l2649
I guess there's always someone who complains about you changing something and adding this soft background music. But I really like it. And I love the Music Bakery music, it's oldschool and reminds me of my childhood.
I have a similar problem with the SA GX-550. I also have a copy of the schematic and I am having trouble finding the current flow to the fan motor. Also, what is the likelihood of a thermistor in the protection circuit to be messed up and cause the DC motor to fail? Finally finding a replacement DC motor is next to impossible. Any info would be greatly appreciated.
the voltage of the fan is 5 volts, the fan isn't working, probable cause the fan's driver circuitry, to keep it steadily on, you have to disable the fan error sensing, refer to the schematic, remove the 5 transistor's (Q651-Q655) from the fan's driver circuit, the sound will no longer cut-off. after removing the transistors, measure a supply voltage of + -5v located at the two terminals of the 1000uF/25v electrolytic capacitor near to the 4 crystal diodes which are connected to the output of the sub-transformer. the sa-gx550 has an error sensing system that whenever the fan driver's circuit is malfunction it disconnects the speaker connection through its relay to protect the power Integrated Circuit (IC) from overheating. please take note, since the sensor is disabled and the sound will no longer cut-off you have to add another 12v fan on top of the heatsink to protect the IC from overheating.
@@chrish.3564 your very welcome. thank you. to add, the measurement at the terminals of the capacitor should be less than 5 volts to supply the fan, that is, if the fan is still working, if not you may replace it with an 80mm 12v fan using a separate power supply.
oh my, I needed this video in my life right now, I have 3 Technics same problem, they all run hot and I can smell the circuit burning, do you know where I can have this fixed on all 3 amps..where are you located I'll send them to you
Is this receiver similar to a SA DA10? I have a similar issue. The left channel is very weak, but only with the analog inputs. The Digital ones are strong.
Are you serious? You didn't read what I wrote. I'm not talking about the balance control being at the center detent. The left channel is weak when listening to the system when an analog input is used (i.e. The Turntable, cassette deck). When a DIGITAL input is used (I.e. the Fibre Optic input of a CD, DVD, etc.), there is no such issue. All channels (as it is a surround receiver), are strong and clean. Anyone else have any possible solutions? A control board? An output transformer? I'm not sure if the Analog and Digital input paths are using the same control boards / output transformers or not. Thanks
Great video! Quick question! I have a Technics SA-R477 receiver. It works great except when you turn up the volume the fan gets very noisy. Can I lubricate the original motor? The fan motor in my unit has wire leads not the quick disconnect that you had in your repair. Can you give me the mfg and part number for the replacement fan motor used in my SA-R477 receiver? Thank you for the great video.
Sorry have no idea the part number. You would need to track down a manual for that and that is something you would have just as much luck doing as i would.
The grey rings of death lol. Smashing job, i like it when manfacturers think about servicing. Some of the old ones had almost the whole bottom come off for service, great access to all the soldering :-D. I've never liked p.a modules, i've had too many stk/other/sanken die.
I have a similar model technics su-a800 speaker relay not clicking, I have -49 volts on both legs of both the relays and the manual says -49 too, can't understand what could go wrong, if you could please help me out.
Speaking of Technics, I have Technics SA-106 Stereo Receiver along with FM and AM radio, the condition I checked that thing out, the left channel speaker is getting weird with crackling sound telling me that the IC has to be replace because, the IC is actually toast to the point it cannot provide the sounds any good. Hopefully someday when I know how to change the light bulb at the front panel, it would be great to give out good looking with either incandescent, or LED.
Hmmm, I wonder who designed this thing? I guess they didn’t realize the heat-sink fins should be parallel to the airflow, not perpendicular to it? Not much room between the heat-sink and that big, honkin’ transformer for much airflow to get by. 🤔
Truth. When at low volume, these always run quite hot. This is a reason so many of them suffer cracked solder joints - age and heat. The fan does a decent job of pulling the heat out when the unit is turned up high enough, but by then, pictures start falling off the walls. :) When I first saw these in stores, I quickly decided to avoid them because of the lack of ventilation and the high heat. Decided to buy a Pioneer instead, got a lot of years out of that one too.
once i have a customer who came with an audio amplifier and a separate tuner . He put the power cord to the back of the amp and the tuner to the wall and said to me that i have no sound....
I don't know why, but I laughed out loud at that because that does happen. It's like someone using an s-video cable and then wondering why there's no sound with the video, not realizing the S in s-video means "separate" or "separated" (Y/C) as opposed to "sound."
I have a 505. Its been in a closet for 12 years. No sound. Tje fan also doesnt come on. But i did take it out and test it. It works fine. Do you tjinls its a solder connecton. Or something more serious. I had it fix only 6 months before it blew again. I dont see any signs. Of service
Do you think this could be the same fault on my friends technics SA-EX500. He sad he had som bad speaker connection and the cut offs. So my thoughts are solder the speaker connections, solder the same you did except they may be on different places on the EX500 and check the fan?
I have a sa gx550 that plays fine up to level 4 on volume, if i go to level 5 it overloads in about 15 sec. Fan never comes on and i checked the fan and it is 20 Ohms. Hooked fan to a AA battery and it spun, resoldered the IC's, getting - 1v on A, -14.6V on B and 0 then -1 for a milla second on c on cable to motor circuit when it over loads. Cleaned connector to fan but it doesn't get juice? not sure if i need to look at the card that attached to the fan? Not sure how to check the Q651,q652 or q653? Or is it a problem with IC601 or 602 because it plays fine a low volume? Please help i can try to get you any info to get this going. Alos it does not overload when speakers are turned off and at full volume. All other features work. If i put another fan on the ic's to blow cool air it doesn't make a difference, has to do with volume being turned up and fan not turning. Help me please... Thanks
Hi, my fan motor is fine, I tested it. The Technics SA AX540 unit never turns it on even when the unit gets very hot. From what I recall , it’s always been this way. The problem is now it’s going into overload and sound is cutting in and out. I cleaned the input select pots, this helped but it still overloaded after about 30 minutes of moderate volume. I will resolder the connections as you just did, but I’d like to get the fan turning on. Any suggestions would be appreciated. Thanks.
@@12voltvids Then I will use 60/40 leaded solder when I resolder the main IC chips on my Technics SA-DA10 receiver. It has an amazing sound and it put out a lot of heat which I guess could have ruined some solder joints.
Hello, i just found your video and i find it very helpful, but unfortunately i did not find the answer to my problem. I have the SA-GX 350 model and had the same problem with the sound cutting off, i traced the problem to be the ventilator, the contact pins where to lose so i ended up soldering the cable directly to the motherboard and that fixed it. It worked just fine for a long period, but now while in use it's turning off (standby) and then on again, sometimes after turning off it takes some time to turn itself back on. If i press the power button, twice, then it turns on again. The power button is not sticky, it is functioning as it should. Any ideas on what it could be? Thanks in advance.
I am a bit sad to see that most of these fan cooled units from many of the manufactures made years ago are living up to my low expectation of them. Fans only work well for so long, and IF everything is kept clean. Yeah, make a cheap stereo with undersized heatsinks and cool it with a fan, how long do you think it really will last?
Help❗❗ In my technics SH-EH600 system, the bass is not reading The output is going by treble and bass seperately. There is no signal from bass. Please tell me a solution 😀
I have an SU-G88 technics AV control amplifier, the display is active at on position, but the sistem not have sound . you think i have review all the points of contact in the chasis..? sorry for my english, i am from MEXICO.
Hi sir good day.. i have technics amplifier Su-x320 model.. its work well.. the issue is sometimes when i switch on the power button it has no power (no power/ no display on panel) Then sometimes it has.. What seems to be the problem sir? Can u help me sir where i start to check or troubleshoot ? I have a little knowledge in electronics..regards from PH Tnx ahead for the idea sir..
What are your speaker impedance. Many older units were 8 ohms minimum. If you wanted 2 pairs of speakers they need to be 16 ohm speakers as the 2 of them in parallel would drop to 8. If they were 8 ohms speakers that would drop to 4. My luxman can only drive a single pair.
@@12voltvids My speakers are 8 ohms impedance, i think problem is comming from the receiver since i never had any issue with 2 channel at the same time with my speakers. When i plug my speaker in the A channel for example, and setting A + B, sound is muting anyway on all channel if there is nothing on the B channel :/ Also when i plug the left speaker on channel A and right speaker on channel B, it can't play A and B, i have to chose A or B.. Thank you for your reponse !
@@crying34 some amps will put the speakers in series when a+b selected so you would have to have 4 speakers connected. If you had say only 3 the side with a speaker on a and b would have sound and the other nothing because the speakers in series one would be open. All depends on the design. I would have to look up the service manual for the model to see how they are wired. My old sansewage, has a b c a+b, a+c and b+c only. Can not run all 3 together
@@crying34 the good old auto series config waiting setup. You might wonder why they do that. The reason is simple users didn't pay attention to the minimum rating. The amplifier probably has a minimum it's weaker impedance of 8 ohms so putting a second pair of 8 ohm speakers on the B side if they were just switched in parallel the impedance would drop to four ohms which could damage an amplifier that has a minimum rating of 8 ohms. I have a luxman in for service right now LV 103 just like the one that I own. On the back of it it says 8 oh minimum for four speakers you must use 16 ohm speakers. how many people do you think would actually read that? Or understand it? No people will hook up a second pair of speakers and wonder why as soon as they give it volume it goes into protection. At least the luxman when you overload it it kills the sound. I know that because I run six ohm speakers and one of the reasons I stopped using that amplifier in my studio was because I had a Tennessee to sometimes turn it up a little too loud and it would go into protection and kill the sound completely. So what your amplifier does is it protects the app by putting the speakers in series where you switch both on that way running 8 ohm speakers it actually become 16 ohms. Quite a smart design. I wish every manufacturer did that but as you noted if you push the A and the B button together and you've only got one pair of speakers connected you get no sound at all. When I was working in the shop we used to get stereo equipment come in and the complaint was no sound and we put it up on the bench and found that both the A and the B speaker buttons were pushed in and they only had two speakers. It was a waste of our time because we couldn't charge for a no-fault found although I think today if I was still in the business and we had people do that they would be paying you know an estimate fee for wasting our time.
I had a 650 and a da 10 both had that problem I threw them out because I never saw this video they were great sounding .Repair wanted 125 just to open the hood .
At least its designed to work unlike ONKYO AV D class witch is designed to over heat , the fan has NEVER spun so I use a PC fan with a battery from these TOY cordless drills on top .
Just be glad you’re not in software tech support; you wouldn’t believe the number of people who just can’t type to save their lives! Once, I had to check to see if the backup to a Zip disk was working, so I had the customer exit out of the program, and then click on the “Start” button, then select “run”, and type “cmd” and click “OK”. I then asked the customer, “Okay, do you see a black box on the screen that says, ‘see colon backslash greater-than’?” ‘Yes”, “okay, now type in, ‘d as in David, I as in Indian, r as in Richard, a space, e as in Edward, and shift dot-over-the-dot next to the L key’” Do you know what they typed in? “Davidindianrichardaspaceedwardshiftdotdotnexttoell”! And this was because they couldn’t find the “My Computer” icon on the Windows desktop! I’d hate to think what would have happened if they’d been running a Linux distro! I hope no one ever gives these people a hot soldering iron!! 🤠
Thank you for your video it give an idea how to fix my 505. It seems the transformer gives 22v instead 9 v. Now i need to buy it. But I do not where. Some ideas are welcome
I had a 1989 technics system and receiver did same thing 10 years ago. No videos back then on how to repair so i threw away. I've always missed that receiver but yesterday i found one next to the trash dumpster....same things happening to it but with this video ill finally be able to have my technic full system back together again! Thanks.
I'm an Aussie DJ Audio/Visual engineer. When I was a kid.......I'm 57 now, I used to service all the old BW TVs and radios of the era that my friends had and amassed a huge selection of TV and radio tubes or valves as we call em here! The main problems were horizontal and vertical output tubes failing so you'd get that nice beam of light going either way with sound! I fixed them, adjusted the picture geometry and at 12 years of age I charged a dollar which was huge for the 60s and 70s. I was very careful with the high voltage rectifiers, the good old 1B3GT and often fixed the monitors at school and wired up power plugs for many things. I had stacks of 5AR4s and other tubes for radios and hifi amps and often fixed them at the amazement of other friends parents! If I couldn't fix it, I knew what was wrong and wrote down the info for the techs who always wanted to meet me which was a real buzz for a 12 year old! Like this amp I often used perfectly good second hand parts to fix a problem but my mum said that I had to do it for 50 cents to teach me the value of money. I wish I could go back to those days where people were honest and life was so much simpler! I love your channel. I should've gone to a tech school but back then it was so different than today! Cheers! Andy from OZ!
It's great!!!... Answers to all my questions for today's malfunction))))) Thanks, now I reliably know how to repair my own Technics... You have finally convinced me that I am moving in the right direction... Wholeheartedly!!! )))))))))
DUDE!! You are the BEST!!! SA-GX670 Back to life!
I had the same, had to move to to make the relays kick in. I knew the second I reflowed it, and I heard the joyous sound of the second relay click I had success!
I just absolutely love this receiver. It's a spare, but I also had SA-GX505 since I was in my teens and I saved up 4 paychecks to buy it. I just have such fond memories of this series, even so it's a bit obsolete by today's standards.
Thanks again. Happy New Year 2020!
Edit - My fan was perfect though, but I always babied mine, and kept them perfectly clean.
Also, SA-Gx670 seems a bit "toasty" around DRIVER IC STB area, specifically q735,q737, r740+r743. It's normal, or should I be concerned? I havent had the hood off SA-GC505 much but dont remember anything like that, but it's also not H+ either.
I thought the fans on these were active only when the amp is pushed hard.
@@mikeam3871 yes, that is true
Hello!
Another happy customer... And a quick and classic fix.
Your repair is near perfect, but you should be more attentive to dust problems, as we can hear you cough.
My advise to many technician is to take care of their health and to avoid inhaling it: use a vacuum cleaner or a dust mask!
I used to work as a TV tech some 30 years ago in Paris, and had a colleague who spend days at the hospital with serious intoxication. Cockroaches love dark and hot places, and he sprayed them generously with a bug killer can he always had ready at hand when he opened VCRs, TV sets. But he made the near fatal mistake to inhale the dust he removed and dispersed with a air spray, along with the insecticide. This effective product is also a permanent treatment that set a layer of microcristalline poison. (A Bayer technology I suppose used by many of brands).
We found then it was safer to use first a vacuum cleaner and a paint brush to remove dust, rather to disperse dust everywhere in the shop.
And the result was we had a much safer and cleaner environment.
The cockroaches problem was also partially solved using a sort of fumigation and decontamination box, that was big enough to treat a TV set, open it and vacuum clean it, that was close to a nowadays sand cleaner. No definitive treatment is alas proven safe, and as far as the total environment is cleared, the bugs will always come in...
Later, we did the same thing with computers, and many forced cooling systems, as the fans are accumulating much more dust and contamination. I also advised friends working with domestic appliances like microwave ovens... And the same problems!
You never know if the dust you inhale from an apparatus is toxic or not: you can find fungi, bacilli, asbestos, lead... And many other dangerous contamination.
That cough was staged by the way. In reference to the gopher from Caddyshack after bill murray blew up the golf course and the gopher lived, and coughed twice as he "coughed out all the dirt he inhaled" I do it every time I use the compressor as a joke. Same as a made reference to a line from "True Lies" when my battery died on my laptop. "Battery dead... go and get another one"
Had exactly the same problem on my Technics SU-X502 its a brilliant little amplifier, sounds superb
Just fixed my Tachnics SA GX550 overload problem. Thank you so much for your videoclip. Yes, it was a cold solder at output ICs.
Hey, I thought I'd post a comment here for anyone who has a similar problem on a Technics amp from the early nineties which isn't caused by a bad joint.on the power amp. These Technics amps drive their fans on demand when there is a high power output (only very loud with a lot of bass, etc.). On my receiver the fan would never move and the amp would cut out at high power (drum beats, guitar riffs, any sudden spike of volume). Turns out these amps are designed to shut down speaker output when the fan isn't operating as it should (funnily enough this does not trigger the "over-load" prompt on the main screen). So when you have a similar issue it's worth checking the fan motor, fan connectors and the fan supply board. On my example the solder joints connecting the fan to the supply board were completely busted. Supply board had to come out. Anyway, I thought someone might find this useful. Cheers
😅😅😅 love the ring tone...so good. Wives and electronics, like oil and water baby. Thanks for sharing your electronic experience with us. Cold solder joints and noisy fans...been there, nice that Technics put that removable panel there so you don't have to pull the whole board out. 👍👍
It wasn't her. It was her friends place. She called me on her phone and put the phone on speaker so I could try to walk her through the procedure.
i always loved those huge transformers Technics used.
Wish they'd carried on with it as well, when I picked up my early 90's stack system I very nearly threw it backwards over my head, it was so lightweight! lol
I fixed SA AX610 encouraged by you- thanks!. Cracked solder joints. I didn't see them until using a magnifier. Keeps it out of the landfill. It is a good stereo.
The trick is getting to the fault quickly and using as little as possible in parts so you stand a chance of making money. Good job!
I have an SAGX 690 and it never gave an issue, even when I had it running outdoors for a party at near max all day. It started to rain and we were on the boat. By the time I got back and it was pouring but the system was still blasting. You could see the steam emitting off the amp. This was one of the craziest things I have ever seen with electronics. Amp is still running today in my recording studio.
Good repair, enjoyed this, thanks. Just wondered if you did any explanations on surround sound on your videos? I'd like to learn a little more about things like Dolby SS, Pro Logic, DTS, all the other codecs. Thanks. Also I have a question about audio dummy loads. Can they cause power transistor failure ? I had recently bought a set of dummy loads that is for tube or transformer output it said, it reads 8 ohms. I didn't have the non inductive type as of yet. Anyway I tried it on a old transistor guitar amp, I can't find a schematic for it, but I found it didn't have an output electrolytic cap to speaker, it just goes straight to speaker. I've tried to trace the foils. I changed the old electrolytic caps. The amp is made in the 70s, I found some caps open, some leaky so I replaced them, I replaced the output transistors with new NPNs from mouser 2n3055. Everything checked out and I powered it up, checked it and the amp blew a fuse after 2 minutes of setup looking at a sine wave from my generator on my scope. I found the two new power transistors had shorted/(fused together.) Someone had told the 2n3055 cannot handle as much current as the older ones, I'm not sure of that though. Can you give a little info on the subject? It would be greatly appreciated. Thank you! :)
Thanx for sharing, fixed mine today, thumbs up!
I appreciate you doing this - I have the "OVERLOAD" error on mine which is a Technics SA-DA15. I love the receiver but even without speakers attached it goes into the error. I wish you were nearby to fix mine. What would it cost if it were a simple fix that you did to the SA GX550? I plan to take it out of storage and see if the fan comes on as you did but without the speakers attached. I don't have any equipment like you nor am I familiar with them.
Love the way you melt tabs on the fan motor plastic to keep it on. I’ve seen you do this a couple times now, I gotta try it!
Oh, the Vintage pre-amp sounded so much better thru headphones... just sayin.
9:34 Why was there a motor on the volume control?
Edit: Actually, it might be how it detects how much the knob turns but I'm not sure.
Remote volume control. The motor turns the analog volume control.
I'm a tech at a car dealer and spend tons of time trying to explain how someones car works to them even though there's probably a manual with the car for the owner that might be able to explain it to them better. Probably, but they'll never know.
Great video!! Question: when using compressed air from an air compressor, doesn't moisture in it cause problems on electronics?
There is a dryer (silica gel) to dry the air.
Compressed air *is* dry. That is where the water in a compressor comes from.
You may have heard that in a garage where they have a device mounted on the outlet of the compressor that infuses the air with oil so it lubricates the pneumatic devices eg impact wrench etc.
Used to work at a call center, trick is to ask them what make is their tv. Now go find the remote with the same name on it. :)
That doesn't help when both the TV and the dvd/VCR combo are the same brand. The problem in the end was they got the TV on the right input but the dvd/VCR was on the VCR mode and because there is no cable connected it was displaying "no signal" on the TV.
0:50 - This unit probably would not NEED a fan there were more vent holes on the top cover!
They use the fan as an exhaust fan to pull heat out from the unit. The reason they went to this design in the first place was because of all the idiots fire stacking their components in a cabinet with glass doors. The idea was the fan would blow the hot air out the back.
18:55 - that's theme to some TV show - possibly PBS related. Thought it was Hometime.
That is entire possible. The tune is called "Corporate Image" licensed by the music bakery. The composer, Jack Waldenmeier has composed over 800 tunes and jingles used in TV, Radio, Film.
There is a car show on TV called Driving Television, and until this season they used musicbakery track passport as their voice over track, and Street Beat as the closing credit music. Very popular indeed. If you call Blackberry about a problem with your phone and get put on hold you will hear the track "cityscape" while on hold.
I have the same model and had exactly the same problem,did the fix to cold soldered joints but couldn't find a replacement motor.What is the size?24 mm?Also what voltage is it?
It is just a CD player motor. The one I put in came put of an old pioneer changer.
@@12voltvids Like this one?I do not have any old stuff around.www.ebay.com/itm/MABUCHI-RF-310TH-11400-DC-3V-5V-6V-24mm-Diameter-Mini-DC-Motor-for-CD-DVD-Player/262934050686?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m1438.l2649
I guess there's always someone who complains about you changing something and adding this soft background music. But I really like it. And I love the Music Bakery music, it's oldschool and reminds me of my childhood.
I punch it in to fill the void where there was nothing being said.
You saved my receiver, thank you.
I had a SU-G50 with a bad ground connection/screw cutting out when you pressed on the board.
Hello, i have a sa-gx670 and i dont have Sound, where I can send you a video? Tnx
Love your work!
I have a similar problem with the SA GX-550. I also have a copy of the schematic and I am having trouble finding the current flow to the fan motor. Also, what is the likelihood of a thermistor in the protection circuit to be messed up and cause the DC motor to fail? Finally finding a replacement DC motor is next to impossible. Any info would be greatly appreciated.
the voltage of the fan is 5 volts, the fan isn't working, probable cause the fan's driver circuitry, to keep it steadily on, you have to disable the fan error sensing, refer to the schematic, remove the 5 transistor's (Q651-Q655) from the fan's driver circuit, the sound will no longer cut-off. after removing the transistors, measure a supply voltage of + -5v located at the two terminals of the 1000uF/25v electrolytic capacitor near to the 4 crystal diodes which are connected to the output of the sub-transformer. the sa-gx550 has an error sensing system that whenever the fan driver's circuit is malfunction it disconnects the speaker connection through its relay to protect the power Integrated Circuit (IC) from overheating.
please take note, since the sensor is disabled and the sound will no longer cut-off you have to add another 12v fan on top of the heatsink to protect the IC from overheating.
@@beausky4100 Thank you very much for your time.
@@chrish.3564 your very welcome. thank you.
to add, the measurement at the terminals of the capacitor should be less than 5 volts to supply the fan, that is, if the fan is still working, if not you may replace it with an 80mm 12v fan using a separate power supply.
i wanted to know.. what kind of power amp module are those ?ive never seen em are they technics made devices ?
Yes Panasonic made them in house.
Prob stk's or Darlington power packs. Obsolete
@@MrTopsoil911
Yup once you blow them up they are toast
oh my, I needed this video in my life right now, I have 3 Technics same problem, they all run hot and I can smell the circuit burning, do you know where I can have this fixed on all 3 amps..where are you located I'll send them to you
Is this receiver similar to a SA DA10? I have a similar issue. The left channel is very weak, but only with the analog inputs. The Digital ones are strong.
Its the balance control
@@thedogememesproductions6354 How can I fix it? Thanks
Is it set to the middle on were it says balance?
Are you serious? You didn't read what I wrote. I'm not talking about the balance control being at the center detent. The left channel is weak when listening to the system when an analog input is used (i.e. The Turntable, cassette deck). When a DIGITAL input is used (I.e. the Fibre Optic input of a CD, DVD, etc.), there is no such issue. All channels (as it is a surround receiver), are strong and clean. Anyone else have any possible solutions? A control board? An output transformer? I'm not sure if the Analog and Digital input paths are using the same control boards / output transformers or not. Thanks
Try banging on the protection relay and see if b it turns on the speakers
Great video! Quick question! I have a Technics SA-R477 receiver. It works great except when you turn up the volume the fan gets very noisy. Can I lubricate the original motor? The fan motor in my unit has wire leads not the quick disconnect that you had in your repair. Can you give me the mfg and part number for the replacement fan motor used in my SA-R477 receiver? Thank you for the great video.
Sorry have no idea the part number. You would need to track down a manual for that and that is something you would have just as much luck doing as i would.
The grey rings of death lol.
Smashing job, i like it when manfacturers think about servicing.
Some of the old ones had almost the whole bottom come off for service, great access to all the soldering :-D.
I've never liked p.a modules, i've had too many stk/other/sanken die.
Awesome video, I actually have this in my shop that the previous owner left.
I have a similar model technics su-a800 speaker relay not clicking, I have -49 volts on both legs of both the relays and the manual says -49 too, can't understand what could go wrong, if you could please help me out.
I have a Technics SA-GX190 that has gone into standby mode. How do I get it off?
i hope you are berry good, thanks for your tutorial is the best in these technics amplificators.
SA-GX770 Exact same problem. Since I don't have a soldering gun I took it in. $80 later I have my old, great sounding stereo back.
Speaking of Technics, I have Technics SA-106 Stereo Receiver along with FM and AM radio, the condition I checked that thing out, the left channel speaker is getting weird with crackling sound telling me that the IC has to be replace because, the IC is actually toast to the point it cannot provide the sounds any good. Hopefully someday when I know how to change the light bulb at the front panel, it would be great to give out good looking with either incandescent, or LED.
Hmmm, I wonder who designed this thing? I guess they didn’t realize the heat-sink fins should be parallel to the airflow, not perpendicular to it? Not much room between the heat-sink and that big, honkin’ transformer for much airflow to get by. 🤔
Truth. When at low volume, these always run quite hot. This is a reason so many of them suffer cracked solder joints - age and heat. The fan does a decent job of pulling the heat out when the unit is turned up high enough, but by then, pictures start falling off the walls. :) When I first saw these in stores, I quickly decided to avoid them because of the lack of ventilation and the high heat. Decided to buy a Pioneer instead, got a lot of years out of that one too.
I've used my technics sag 9057 since 2003 and it was used. Fan motor just went on it the other day.
once i have a customer who came with an audio amplifier and a separate tuner .
He put the power cord to the back of the amp and the tuner to the wall and said to me that i have no sound....
I don't know why, but I laughed out loud at that because that does happen. It's like someone using an s-video cable and then wondering why there's no sound with the video, not realizing the S in s-video means "separate" or "separated" (Y/C) as opposed to "sound."
I have a 505. Its been in a closet for 12 years. No sound. Tje fan also doesnt come on. But i did take it out and test it. It works fine. Do you tjinls its a solder connecton. Or something more serious. I had it fix only 6 months before it blew again. I dont see any signs. Of service
Do you think this could be the same fault on my friends technics SA-EX500. He sad he had som bad speaker connection and the cut offs. So my thoughts are solder the speaker connections, solder the same you did except they may be on different places on the EX500 and check the fan?
Nice work! Great vid.
Motor part number? Or a good source for alternative? Mine is dying.
Good job
Great video. Can you give us an idea of want a repair shop would charge for a service like this.
A shop would probably charge in the 100 range minimum for this.
I have a sa gx550 that plays fine up to level 4 on volume, if i go to level 5 it overloads in about 15 sec. Fan never comes on and i checked the fan and it is 20 Ohms. Hooked fan to a AA battery and it spun, resoldered the IC's, getting - 1v on A, -14.6V on B and 0 then -1 for a milla second on c on cable to motor circuit when it over loads. Cleaned connector to fan but it doesn't get juice? not sure if i need to look at the card that attached to the fan? Not sure how to check the Q651,q652 or q653? Or is it a problem with IC601 or 602 because it plays fine a low volume? Please help i can try to get you any info to get this going. Alos it does not overload when speakers are turned off and at full volume. All other features work. If i put another fan on the ic's to blow cool air it doesn't make a difference, has to do with volume being turned up and fan not turning. Help me please... Thanks
Hi, my fan motor is fine, I tested it. The Technics SA AX540 unit never turns it on even when the unit gets very hot. From what I recall , it’s always been this way. The problem is now it’s going into overload and sound is cutting in and out. I cleaned the input select pots, this helped but it still overloaded after about 30 minutes of moderate volume. I will resolder the connections as you just did, but I’d like to get the fan turning on. Any suggestions would be appreciated. Thanks.
Do you have to use the same type of solder, leaded or lead free, as what was used originally when that Technics reciever was made.
No I use 60/40 leaded
@@12voltvids Then I will use 60/40 leaded solder when I resolder the main IC chips on my Technics SA-DA10 receiver. It has an amazing sound and it put out a lot of heat which I guess could have ruined some solder joints.
the hdmi buttom sounds like my trade in the HVAC .
Hello, i just found your video and i find it very helpful, but unfortunately i did not find the answer to my problem. I have the SA-GX 350 model and had the same problem with the sound cutting off, i traced the problem to be the ventilator, the contact pins where to lose so i ended up soldering the cable directly to the motherboard and that fixed it. It worked just fine for a long period, but now while in use it's turning off (standby) and then on again, sometimes after turning off it takes some time to turn itself back on. If i press the power button, twice, then it turns on again. The power button is not sticky, it is functioning as it should. Any ideas on what it could be? Thanks in advance.
Does this happen on the SA-DX950? As sometimes I am sure I hear my volume go down on its own...
I have technics su-g90 and the problem is the cooler. And check of voltios 6. the clean and not works. What is this?
I have two Technics reciver one is
SA-R430 and SA-R477, no sound on both. Can you please help me to fix them?
I am a bit sad to see that most of these fan cooled units from many of the manufactures made years ago are living up to my low expectation of them. Fans only work well for so long, and IF everything is kept clean. Yeah, make a cheap stereo with undersized heatsinks and cool it with a fan, how long do you think it really will last?
Help❗❗
In my technics SH-EH600 system, the bass is not reading
The output is going by treble and bass seperately.
There is no signal from bass.
Please tell me a solution 😀
I did have the biggest model of the line till last year i gave it away and got a pionner vsx1021
I have an SU-G88 technics AV control amplifier, the display is active at on position, but the sistem not have sound . you think i have review all the points of contact in the chasis..? sorry for my english, i am from MEXICO.
Does this dc motor have any special characteristics? Can I use a 12v motor in my GX550???
Nothing special about this motor. Just a small DC motor. If it fits, use it.
Hi sir good day.. i have technics amplifier Su-x320 model.. its work well.. the issue is sometimes when i switch on the power button it has no power
(no power/ no display on panel)
Then sometimes it has..
What seems to be the problem sir?
Can u help me sir where i start to check or troubleshoot ? I have a little knowledge in electronics..regards from PH
Tnx ahead for the idea sir..
Did you say to her “ have you tried turning it off and on again “ like a phone technician 😂
Hello there ! On my SA GX130, i can play A channel, B channel perfectly but i cant play BOTH channel on, do you know where it can came from ? thanks !
What are your speaker impedance. Many older units were 8 ohms minimum. If you wanted 2 pairs of speakers they need to be 16 ohm speakers as the 2 of them in parallel would drop to 8. If they were 8 ohms speakers that would drop to 4.
My luxman can only drive a single pair.
@@12voltvids My speakers are 8 ohms impedance, i think problem is comming from the receiver since i never had any issue with 2 channel at the same time with my speakers.
When i plug my speaker in the A channel for example, and setting A + B, sound is muting anyway on all channel if there is nothing on the B channel :/ Also when i plug the left speaker on channel A and right speaker on channel B, it can't play A and B, i have to chose A or B.. Thank you for your reponse !
@@crying34 some amps will put the speakers in series when a+b selected so you would have to have 4 speakers connected. If you had say only 3 the side with a speaker on a and b would have sound and the other nothing because the speakers in series one would be open. All depends on the design. I would have to look up the service manual for the model to see how they are wired. My old sansewage, has a b c a+b, a+c and b+c only. Can not run all 3 together
You were totaly right ! Made a test with two pair of speaker and it works as it should.
Thank you !
@@crying34 the good old auto series config waiting setup. You might wonder why they do that. The reason is simple users didn't pay attention to the minimum rating. The amplifier probably has a minimum it's weaker impedance of 8 ohms so putting a second pair of 8 ohm speakers on the B side if they were just switched in parallel the impedance would drop to four ohms which could damage an amplifier that has a minimum rating of 8 ohms. I have a luxman in for service right now LV 103 just like the one that I own. On the back of it it says 8 oh minimum for four speakers you must use 16 ohm speakers. how many people do you think would actually read that? Or understand it? No people will hook up a second pair of speakers and wonder why as soon as they give it volume it goes into protection. At least the luxman when you overload it it kills the sound. I know that because I run six ohm speakers and one of the reasons I stopped using that amplifier in my studio was because I had a Tennessee to sometimes turn it up a little too loud and it would go into protection and kill the sound completely. So what your amplifier does is it protects the app by putting the speakers in series where you switch both on that way running 8 ohm speakers it actually become 16 ohms. Quite a smart design. I wish every manufacturer did that but as you noted if you push the A and the B button together and you've only got one pair of speakers connected you get no sound at all. When I was working in the shop we used to get stereo equipment come in and the complaint was no sound and we put it up on the bench and found that both the A and the B speaker buttons were pushed in and they only had two speakers. It was a waste of our time because we couldn't charge for a no-fault found although I think today if I was still in the business and we had people do that they would be paying you know an estimate fee for wasting our time.
I had a 650 and a da 10 both had that problem I threw them out because I never saw this video they were great sounding .Repair wanted 125 just to open the hood .
Luv the kitty :)
The power rating on this Technics is under rated.
my problem is where to find the power module.
Thanku sir.
At least its designed to work unlike ONKYO AV D class witch is designed to over heat , the fan has NEVER spun so I use a PC fan with a battery from these TOY cordless drills on top .
Dont get me started on onkyo. Piece of shit they are.
Just be glad you’re not in software tech support; you wouldn’t believe the number of people who just can’t type to save their lives! Once, I had to check to see if the backup to a Zip disk was working, so I had the customer exit out of the program, and then click on the “Start” button, then select “run”, and type “cmd” and click “OK”. I then asked the customer, “Okay, do you see a black box on the screen that says, ‘see colon backslash greater-than’?” ‘Yes”, “okay, now type in, ‘d as in David, I as in Indian, r as in Richard, a space, e as in Edward, and shift dot-over-the-dot next to the L key’” Do you know what they typed in? “Davidindianrichardaspaceedwardshiftdotdotnexttoell”! And this was because they couldn’t find the “My Computer” icon on the Windows desktop! I’d hate to think what would have happened if they’d been running a Linux distro!
I hope no one ever gives these people a hot soldering iron!! 🤠
Easy repair, for a change huh?
Thank you for your video it give an idea how to fix my 505. It seems the transformer gives 22v instead 9 v. Now i need to buy it. But I do not where. Some ideas are welcome
Motor model please !
Have no idea.
Good video, Question could you repair my Sa-gx505?
Probably
sorry i might be texting too late ! im in california .
Same time zone here.
How about my wife? Was going nuts as the remote was not working, until I pointed out that she had it upside down and not pointing at the TV.
Thanks for the instructive videos. Only the bit of ranting about your wife was a bit embarrassing; not too respectful.
Hola por favor lo podrías traducir al español al video
Thats why i hate PPJ aka plastic piece of junk vintage amps are always better. I refused to repair those amps. My specialty is vintage gear
Just picked up 2 antique radios today for future projects. An old GE and a Marconi. Now THOSE are VINTAGE.
Cut on off store in nyc
I am having a similar problem, posted on Audiokarma - audiokarma.org/forums/index.php?threads/technics-sa-tx50-in-overload-protection.892879/
101
The fans job is too bad..!!..
My brother has a sony. And works fine.