This video, even after three years, is very useful. Thanks. I was just given a Technics SA-340, pretty clean. Its FM band does not work. Nothing at all. I'll look into it, and already found some leaking caps that needs replacement. Thanks again. Your way of explaining, slowly and in details, helps a lot those, like me, who would like to keep these electronics alive, instead of trashing and buy new cheap stuff. Cheers !
I have this receiver. Mine's in great condition, no problems with the sound quality, all the original lamps even work! At least it did when i put it in my "dead electronics room" (aka workshop) when it was upgraded 18 years ago! I'm sure those caps are all crusty by now, lol. I may just dig it out and give it a try sometime.
Thanks for sharing. As a kid of 16 , I found this receiver at a swap meet. I think I paid 20 bucks for. I found the out put blows and some one bugged up the circuit board. I installed new heat sinks . They were also missing. Repaired the board , and new out puts. I did get an A that year in radio tv repair. Learned a lot playing around with this stuff. Thanks for sharing. Brought back soon good memories.
"Free" time is right, certainly not doing this for the money, doing it for the fun of it, from the fixing to the filming and beyond! If you enjoy the depth check out Electronics Old and New by Michael Caldeira, has channel is awesome. Thanks for watching!
Hi @Telefunkian ... great video !!!!. I have recently bought a SA-202 and I need to repair it. Same issue, one channel is dead. Where did you get the schematic? I have been looking for it and it's seem only to be found in hifiengine, but I'm not member and they are not accepting new accounts ... could you please share it?
It's a typo. I believe the treble center frequency is 10kHz, just like it's predecessor, the SA-200, and many others in the SA-x00 line. I have a SA-202 in my diningroom and a SA-200 in the garage. I do prefer the looks of the SA-200 better. Both treble controls are easy to hear the boost or cut of the 10kHz frequency. I don't think I'd be able to hear it if it was 20kHz. I've changed a number of the Darlington power packs too. They're pretty tough but can fail. My favorite is the SA-500. It uses discrete output transistors and is stunning in its looks, features, and performance. Great analytical video !! Hey, I bet you can fix some of Geddy Lee's classic analog synths !!! Good point about how competitive the industry was and every penny counts !
Fantastic tutorial. I want to work through our SA-300 with my son and this is such a great orientation. It plays, but left channel seems to be out - although the balance knob doesn’t control either. The volume had a lot of drop out points when we first plugged it in, but it seems to be okay now. Haven’t tested radio or phono inputs. Thank you for doing this style video. Did you print out the schematic and tape pieces together? Having that there seems like a great idea during trouble shooting.
Ray, Thanks for your comments. The first thing I do whenever I begin working on a piece of gear is get a hold of the service manual and then piece together the schematic and board layout diagrams, using photoshop if I have to stitch them together, and print them on 11x17 paper (tabloid). I then import the schematics into Illustrator and use Illustrator to annotate them, draw coloured lines etc as I go along. You could use Powerpoint or Adobe Acrobat as well. Good luck with your project, sounds like a great father-son time!
This sheet of metal was painted black from the beginning, or maybe it was your idea to paint this sheet of metal? It seems incredible to me that this sheet metal (radiator) is painted?
Thank you for watching and for your question. It has been a long time since I have looked at the schematics but I believe these darlington power packs short when overdriven, possibly when presented with a load that was itself inadequate in some way, such as a partially shorted speaker voice coil?
I have a sa-101 which was made up to 1979 and is the same as the sa-202 it has a visibly burnt diode d-107 and the right side has failed with badly any distorted sound these sterios have a very clean powerful sound everything else works the lighting panel could it be fixed or parts
David, I'm sure your SA-101 could be fixed, though it is likely going to need much more than a diode. Unless you are able to do the work yourself or have a good friend willing to do it for you it might fall into the category of 'beyond economical repair'.
This tutorial is excellent. Thank you for posting it. I am working on a Technics SA-303, which is quite identical to the illustration model. It had the dreaded’ powers on, no sound’ disease. I replaced most oh the caps, and even the power filter caps. No joy upon firing it up using the Variac. So, I replaced the STK 1039 packs just today, and will fire it up soon. I am not super confident, since both channels were not making sound. I am hoping it will be the answer. Do you have any ideas before I power it up? Again, thanks for this video- it’s excellent.
Mark, Thanks for watching, for your feedback and question. I would examine the schematic, find the driver transistors that power the STKs and check them with a multimeter, they may have blown as well. They will be a lot less expensive than the STKs! Keep going, I'm sure you will fix it and the feeling of satisfaction will be worth it!
@@telefunkian Thanks for your help. I did use the schematic, and long story short, I powered on the 303, and all inputs are working. I feel great in knowing I brought this receiver back. to life, and I am enjoying listening to its great sound. Thanks again for putting this video up, it gave me confidence to dig deep into the issues related to the SA-303 not working.
Bob, by all accounts the upper end of the SA series are supposed to be pretty good receivers. Unless yours has been subject to abuse it should be pretty good, and with 125 watts or so of power, I doubt it would have spent much time being overdriven. At most a recapping might be in order? Good luck!
David, First thing have a look online for the service manual for the sa-101 and see if it tells you what kind of diode that might be, in all likelihood, either a small signal diode, a rectifier diode or a zener diode. Then search on line for the part number listed in the service manual. It may be obsolete, so then search for 'xyz replacement'. Good luck and thanks for watching!
I am also trying to repair a Technics SA 200, which only has the right channel properly working while the left channel is not working at all. I took out both Darlinton Power Pack stk 0029 in order to replace the one from the left output. Here I have a question, since the stk 0029 is impossible to find in our local market. It is OK if I chose the Darlinton stk 0049? I saw the Data sheet of this component and the differences are in the Thermal Resistance from 2.4 to 2.0 ªC/W and the Supply Voltage at Rated Power Output from +/- 25.0 to +/- 31 V. Thanking you in advance for your comments.
Freddy, My understanding is that assuming the STK is the only thing wrong with the amp that replacing a STK0029 with a STK0049 will 'work' but you may run into PSU or thermal limitations. I would suggest replacing both if economically feasible.
@@telefunkian Thank you very much. I also removed from the line of the left channel a total of 21 capacitors and tested them. I found 12 capacitors damaged, out of specification or leaked. I am planning the re cap of all of them. I will keep you posted.
Great tutorial. I have one problem with my SA505 unit. I tried to connect my speakers with the unit on. Big mistake, I cross the positive and the negative weir and then the received do not by pass the safety light. So, no sound is coming out. What do I need to do to fix the problem?
Jose, I'm afraid I don't have a service manual for the 505 so I will have to speculate. You may have blown the power amp chips, which are STK1060K. These can be found on line or you may be able to find replacement equivalents from NTE or ECG. They are not so common but I think this vendor has some... www.sphere.bc.ca/test/semis.html#catalog. The amp also has a speaker protect circuit that the 202 does not have, but I think it is just a DC detection / protect circuit. Sorry I can't be of any more help. Thanks for watching!
BruceLynn, Only you can decide if it is worth it. It might not be worth the money in the sense that you might spend more time and energy than it is 'worth', but if you are doing it for fun and enjoy the process of learning and trouble shooting then how can you put a price on that? (Do you mean a Technics SA-R230?) At very least perhaps open it up and see if there is anything obvious? Just be safe!
10-4, I should know that but for some reason my brain fills in overload when I see it. Especially when I am trying to talk, do something else and think about what to say next at the same time!
I always wondered what the manufacturers think about this. So I took the time to research this a bit - absolutely pointless, but fun: - Fluke seems to mostly refer to the OL indication as an "voltage overload" (e. g. Fluke 179 user manual) or "overload input" (189 user manual) in its user manuals. For voltages this certainly makes sense, not as much for resistance, diode mode etc. - Agilent U1272A: They explain it as "Overload (the reading exceeds the display range)" - Brymen (BM789) doesn't explain what "OL" stands for Bench DMM often show more explicit text: - Agilent 34401A: "OVLD", clearly meaning overload - Keysight 34465A: "Overload" - Keithley DMM 6500: "Overflow" For me the take away is: - Fluke and Agilent seem to explain it as overload, *not "open line"* - Open line would be confusing as well, because it has nothing to do with "line" voltage - For resistance/diode mode it makes sense to interpret it as "open lead"
Your video was informative and educational but with the exception of your ridiculous comment you made of Spain. You stated in your video that you purchased on EBay the AN 7060 diff Amp.from “out of all places Spain” What do you mean “out of all places?” Spain is not technological deprived and is not a backward nation. Spain is one of the most industrialized countries in the world. I don’t find it a surprise that you were able to get the electronic component you needed from Spain.
Well my apologies if I offended you, I meant that it was surprising to me that I found the component I was looking for on the other side of the planet, as opposed to the country it was made in, or an country that is known for its marketing of obsolete chips, such as China, which is a more common source (if not the most common source) of such items. That is what I meant by 'of all places'. I don't believe I implied anything negative about Spain, I certainly didn't mean to! Thanks for watching, I'm glad you enjoyed the rest of the video.
