Mike-L Posted October 26, 2015 Share Posted October 26, 2015 One of my 1200's won't turn on anymore - no red light, no quartz light, no movements. I've changed the fuse, which hasn't made a difference, but haven't tried anything else. I'm wondering if I've blown a fuse internally somewhere. Anyone got any ideas? Cheers 1 Quote Link to comment Share on other sites More sharing options...
Guest Symatic Posted October 26, 2015 Share Posted October 26, 2015 i think there are fuses inside too. how hapy are you cracking stuff open and poking around? if you have a miltimeter you could continuity test the fuses inside. Quote Link to comment Share on other sites More sharing options...
Mike-L Posted October 26, 2015 Author Share Posted October 26, 2015 Ah cool. Thanks Sy. I have a few of those glass tube fuses around too. Quote Link to comment Share on other sites More sharing options...
Dubba Dutchdj Posted October 26, 2015 Share Posted October 26, 2015 dat thread tittle 6 Quote Link to comment Share on other sites More sharing options...
Guest rasteri Posted October 26, 2015 Share Posted October 26, 2015 Make sure you note that all the fuses in the 1200 are time-delay type (T). It's usually the 250mA one that blows. Quote Link to comment Share on other sites More sharing options...
Mike-L Posted October 26, 2015 Author Share Posted October 26, 2015 dat thread tittle I was rather hoping someone would come back with "If your having turn problems I feel bad for you son..." Make sure you note that all the fuses in the 1200 are time-delay type (T). It's usually the 250mA one that blows. So I need a fuse with T written on it somewhere? Edit: I just checked and I only have 800mA ones & I can't see time-delay written anywhwere - it says quick blow on them. Thanks for the info Rasteri. Edit Edit: Ive just seen the time-delay ones on Maplin's website - thanks again. 2 Quote Link to comment Share on other sites More sharing options...
Jam Burglar Posted October 27, 2015 Share Posted October 27, 2015 Make sure you get the right fuses, don't just throw any old thing in there. Check the markings on the metal ends for the right fuse. Usually a blown fuse will be obvious from looking at it but you can't always trust your eyes. If you have a multimeter you can put it on ohms and test the fuse. You have to remove the fuse to test it (otherwise the test won't work). Here's how to test a fuse.https://www.swe-check.com.au/pages/learn_fuse_testing.php Multimeters are pretty handy so if you don't have one it's usually worth it to cop one. Quote Link to comment Share on other sites More sharing options...
Jam Burglar Posted October 27, 2015 Share Posted October 27, 2015 dat thread tittle I was rather hoping someone would come back with "If your having turn problems I feel bad for you son..." Make sure you note that all the fuses in the 1200 are time-delay type (T). It's usually the 250mA one that blows. So I need a fuse with T written on it somewhere? Edit: I just checked and I only have 800mA ones & I can't see time-delay written anywhwere - it says quick blow on them. Thanks for the info Rasteri. Edit Edit: Ive just seen the time-delay ones on Maplin's website - thanks again. Quick-blow is no good, you want slow-blow (ayo) 1 Quote Link to comment Share on other sites More sharing options...
Mike-L Posted October 31, 2015 Author Share Posted October 31, 2015 I'm still having issues with this. I tested both internal fuses with the multi-meter & they both look good (not visibly fused & both show about 0.2 Ohms resistance). Any one have any other ideas?Cheers Quote Link to comment Share on other sites More sharing options...
Guest rasteri Posted October 31, 2015 Share Posted October 31, 2015 You up for doing some diagnosis work? If so : Connect your turntable to the mains and switch it on. Then switch your meter to AC voltage and CAREFULLY measure across : 1. The two posts marked "AC" on the power supply board. Should show mains voltage (230), if zero check the power cable or the mains plug 2. The pins on the main board that have blue and red cables wrapped onto them from the transformer. Should show 30V, if zero the transformer's fucked If both of those are OK, we'll have to test the voltage regulator. This is the 3-pin component, screwed to the case of the technics, on a little circuit board towards the rear of the turntable with yellow/red/orange wires going to it. Switch your meter to DC voltage, touch your black probe to the screw at the bottom left of the main PCB and the red one to the leftmost/rightmost pins of the regulator. The leftmost (orange) pin should measure 35v, if not the rectifier is fucked. The rightmost (yellow) pin should measure 20v, if not the regulator is fucked. Quote Link to comment Share on other sites More sharing options...
Mike-L Posted October 31, 2015 Author Share Posted October 31, 2015 Man thank you - that's really helpful. I'll have a go at those things & get back to you. Cheers Quote Link to comment Share on other sites More sharing options...
Guest Symatic Posted November 1, 2015 Share Posted November 1, 2015 was out at Maasia Warrior vs Touch Above Soundsystem last night, the Touch Above dudes had loads of tech issues and ended up on the floor changing fuses using phones and lighters for light.... all worked out in the end tho and their system was HEAVY! was just funny watching the on-the-fly tech fixes Quote Link to comment Share on other sites More sharing options...
Jam Burglar Posted November 3, 2015 Share Posted November 3, 2015 You up for doing some diagnosis work? If so : Connect your turntable to the mains and switch it on. Then switch your meter to AC voltage and CAREFULLY measure across : 1. The two posts marked "AC" on the power supply board. Should show mains voltage (230), if zero check the power cable or the mains plug2. The pins on the main board that have blue and red cables wrapped onto them from the transformer. Should show 30V, if zero the transformer's fucked If both of those are OK, we'll have to test the voltage regulator. This is the 3-pin component, screwed to the case of the technics, on a little circuit board towards the rear of the turntable with yellow/red/orange wires going to it. Switch your meter to DC voltage, touch your black probe to the screw at the bottom left of the main PCB and the red one to the leftmost/rightmost pins of the regulator. The leftmost (orange) pin should measure 35v, if not the rectifier is fucked.The rightmost (yellow) pin should measure 20v, if not the regulator is fucked. Could be a broken on/off switch? That would be pretty easy to test with continuity, no? Quote Link to comment Share on other sites More sharing options...
Guest Symatic Posted November 3, 2015 Share Posted November 3, 2015 Connect your turntable to the mains and switch it on. don't press play!!! Quote Link to comment Share on other sites More sharing options...
Guest rasteri Posted November 3, 2015 Share Posted November 3, 2015 Connect your turntable to the mains and switch it on. don't press play!!! Oh yeah... Don't do that, you'll fuck the motor. Quote Link to comment Share on other sites More sharing options...
Mike-L Posted November 3, 2015 Author Share Posted November 3, 2015 So, I'm still alive which is the good news.1 The AC pins show 240V2 I have two main board pins, one with a blue wire, the other with a yellow wire. (Both connect to a place on the power board which in turn looks connected to the transformer). This shows 65V. Is this an issue? Are these the right pins? EDIT - the low left hand corner of the picture in the youtube link above shows the blue/yellow wires on the pins just like mine.I'm yet to take the other side off the unit. How do I get to the power switch too?Cheers Quote Link to comment Share on other sites More sharing options...
Guest rasteri Posted November 3, 2015 Share Posted November 3, 2015 Yeah 65v is too high - do you have the voltage switch set to 120v or something? If so the regulator is probably blown Quote Link to comment Share on other sites More sharing options...
Mike-L Posted November 3, 2015 Author Share Posted November 3, 2015 No, its definitely set to 240. Quote Link to comment Share on other sites More sharing options...
Guest rasteri Posted November 3, 2015 Share Posted November 3, 2015 did you measure the voltages at the input/output of the regulator? Quote Link to comment Share on other sites More sharing options...
Jam Burglar Posted November 4, 2015 Share Posted November 4, 2015 So, I'm still alive which is the good news.1 The AC pins show 240V2 I have two main board pins, one with a blue wire, the other with a yellow wire. (Both connect to a place on the power board which in turn looks connected to the transformer). This shows 65V. Is this an issue? Are these the right pins? EDIT - the low left hand corner of the picture in the youtube link above shows the blue/yellow wires on the pins just like mine.I'm yet to take the other side off the unit. How do I get to the power switch too?Cheers Seems like it's probably not your power switch since you have voltage to the board. I'm not exactly sure where the switch is in the circuit but I imagine its before the stuff you're pulling voltages from. Also, in all the electronics I've ever dabbled with, I never seen a transformer go bad and you rarely even hear about it (with the exception of flybacks on monitors). They're pretty much just wire wrapped around a coil. Rasteri, do you hear about these going bad on 1200s a lot? Quote Link to comment Share on other sites More sharing options...
Guest rasteri Posted November 4, 2015 Share Posted November 4, 2015 I've never seen a transformer go bad on a Technics. There's a first time for everything though. Transformers die on other stuff all the time however - generally due to overloading. EDIT : I should add, I don't think the transformer has gone bad in this case, unless the primary coil has somehow fused together and has changed the winding ratio. Quote Link to comment Share on other sites More sharing options...
Mike-L Posted November 4, 2015 Author Share Posted November 4, 2015 Cool thanks fellas. I'll test out some of the other suggestions tomorrow night. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.