01 March, 2009

In, out and round about.

In for a penny.

Okay, so I've got this tape deck and radio combo I have to occasionally repair, because it tends to uhm, not go right. Anybody would think I'd just go out there and get a new one, junk the old one, you know. Well, One - I don't have any money, so two, I like to repair my own things where I can. Saves ME money, saves other people's time telling me they can't fix it because they no longer have the repair manual, yada yade yada, gives me the satisfaction of repairing it, and so on. Only ... somewhere in the back of my mind is the nagging thought of "what happens if I can't repair it this time?", and then I get a little worried.

I thought "Right, I've had enough"—I feel like I can't be bothered with having it in the state it was in; namely, not working. Now "not working" to me, means not performing as it was originally built to - in this case, the tape mechanism wasn't playing... something was jammed. I wasn't sure whether it was the transport mechanism or not, though I'd almost ruled out any of the circuitry beyond the playback/record head, and settled on the problem being almost purely mechanical. Those sorts of problems, I can fix. I'm no electronics whiz, can't measure a transistor's hFE without hauling it out of circuit to do so, and besides which, mechanical problems are a bit more amenable. At least, that's what I was hoping the first time I headed inside the case.

Okay. Speakers unplugged, unconnected and hauled off. Then, it's on to the screws. First five screws unscrewed, off comes the back.. hang on, no it doesn't, there's something else holding it on. Damn, where is that fifth scre... ah, there it is, on the base, along with the other six screws I have to probably undo, just to get the sides off. Off comes that screw, the other six screws, all neatly laid out in order so I can put them back on when I've fixed the problem in seven minutes, or so. Then off comes the back, gently, while I figure out which of the three leads have to come off... in this case, I decide, all three can come off. Gently does it, that's AC Flex I'm unbending there. Right. That's the back done. Now, how does... ahh, that's right - once the back comes off, the sides will come off in one assembly. Ease that dial thingymagig off, I'll need that later for the pot on the fine tune control. The buttons will stay in place - they're nice like that. One was missing long before I got the tape deck, so I don't worry about stereo/mono switching any more, though I do toggle the switch back to stereo while I notice it.

I reach inwards to see if I can twirl the motor around, the usual fix for this particular problem - oh, I can't get to it. Now, how the heck did I do this last time, twenty two months ago? (Or was it longer? I can't remember) Ahh, that's right—there's a central screw tying the front to the circuit boards, just in behind the transformer cables from the diode bridge. I reach for that screw, have it out in a matter of seconds. I'm doing well now, I can take the front off, and finally look at the little flippy thing that turns the head around for playing the tape in the right direction. I figure it's sort of up, but not really, and reach for the wheel in the back to twirl it around again, only I still can't get to it. I'd need fingers like spiders legs with the strength of cabling to deal with that... right. Time to take the whole tape transport system out - luckily it's all on one lump of metal, secured by four easy-to-reach screws. I have them off, also in a matter of seconds, also laid out neatly so I can put them all back in the order I took them out in. You can't be too careful when you're doing this job - no sense in having three more screws left over when you've finished than when you've started. It's off with the rubber band for the digits capstan, that always comes off anyhow, so it might as well come off properly now.

I finally get my fingers on to the wheel concerned, spin it around some until I hear a satisfying click from the mechanism, don't bother to check the head's flipped around, as that's what usually happens anyhow, right? Everything looks good, so I put mechanism back, screw the four screws back into place, and even remember to put the capstan band back on. I'm hot to trot as I put the front back on, uhm, wait a minute, something's not fitting. Oh, that's right. The spike for the direction-switch mechanism popped out from underneath the screw that was holding it down so the tape mechanism would go around to begin with. This is beginning to be a little unfunny. Undo the teeny tiny little screw (I've had to find a third screwdriver to take this one off; as it's so tiny, none of the other screwdrivers have heads that little), and set it aside, with the teeny tiny screwdriver head pointing at it so I can find it again. Put the front on again, good, it all fits.

Put in the little screw, then the sides, then put the back on... oh, hang on, I've got to connect those three leads back so they don't short to anything inconvenient, like the hot side of an AC cord, for example. This puppy's not earthed, so being careful of that fact will save someone's life. That's Batt+, Batt -, and ... hang on, this white wire doesn't go anywhere. Oh, that's right, it's the aerial plug. Right. Pull it over to the obvious contact. I can stick the actual telescopic aerial back on it when I get it back into the bedroom. But for now, I'll stretch.... hm. Won't come that far.. Weird. Hang on, pull the back a bit further into the case so the wire will stretch to the contact. Right. That's come far enough now, let's plug it on and have out of.... wait a minute, it doesn't fit. Am I sure, or am I only imagining it? After another couple of minutes of fruitless poking and prodding, I give into the realisation that no, the aerial contact isn't that one. Where the heck is the aerial connector? It surely can't go onto the tuning capacitor, those are NEVER used as aerial inputs except for DC (direct conversion) sets and crystal sets and the like.

Ah, it's up over in the corner, right next to the AM rod. Figures. Right. Let's get my fat little fingers in there—no, they're not actually fat, but they certainly feel like it in this job. Can't quite reach down into the case to get the connector onto the spike. Rats. I know this came off, so it can jolly well go back on! I need more room to work in. Ah, that's right, I just put the sides on, let's see if moving those aside does give me any more room. Reach over to the sides, pull them off in one piece, set them aside. Yup, now there's plenty of room to put everything back. Cool! Put the recalcitrant aerial connector back on, fit the Batt + and the Batt -, and get ready to put the sides back on. Grab the sides, slide them back into place, put back the six screws I pulled out from the base earlier, and eventually reach for the back to put that back into place. I'm almost done now. Reach for the five screws, put them back into place, and tighten them down. We'll test it now.

Out for a pound?

Plug into wall, find tape (Jean Michel Jarre's "Concerts Lyon/Houston") and close door. Press power. Nothing. Flick power switch—handy, that. No lights. Oh, hang on - I can't hear anything without earphones. It's time to grab those from beside the mouse hub, uncoil them and insert relevant plug into relevant hole. Ah, that's right. This tape deck needs that lever depressed so it can play tapes. Depress lever some and screw the tiny little screw back into place. Press power again... hm. No satisfying "Clunk" as I hit power. I flick the switch, only to realise I've flicked it already. I toggle the power switch—nothing. Darn. Here I was thinking this job was going to be simple. Turns out it just got a bit more complicated, and I have to dive back inside to figure out what else is wrong. I've never had this problem with this tape deck before, guess there's a first for everything.

Back into the case, undo the five screws—hang on, gotta power off and unplug. No point in frying myself—this is an unearthed case, remember. Undo five screws; can I do this job without having to remove the sides? I seem to remember that if I don't have to remove the sides, that saves me about six screws, and a bit of work. Take off the back, remove the Batt and aerial lead, set aside screws in the usual order. Reach for the bottom of the circuit board; darn, gotta take off the base anyhow. Guess the sides are coming off after all. Take the screws out, take the bottom and sides off, have a quiet look around to see what I can see on the bottom (copperised tracks, but still somewhat conducting) or the top. Nothing's obviously wrong, so I figure I must have jarred something loose. I put back the sides, the back, plug back into the wall, just to check out. Hm. Nada. Obviously not connected yet. Time to remove the back and the sides again, and have more of a nosey around inside. Hm, better check the fuse while I'm here, I guess. It looks a bit coppered up too, come to think of it. Pull it out, looks good to me, put it back in. Plug into the wall, flick switch, nope. No juice. Unplug, scratch my head and wonder what the heck happened. Pull meter down from bench, set to AC, 1000V, put neg probe on the case of the transformer, the pos probe on somewhere else hopeful. 4V. Nothing really useful. Try DC volts instead ... 4V. Well, at least it's consistently f00kd. Scratch my head some more, flick the power switch off again, look at the back, flick the voltage change switch a couple of times, figuring anything'll work. Plug back in, and flick the power switch. Hey! There's lights this time! Wahey!!! I think my job's almost done.

Now I've sorted that out, I can put the case back together, so I do that, remembering this time to put the back on first so I can connect the aerial lead, then I can put the sides on, then put the back on properly. Plug back into wall, and I decide I'd better run one final test to make sure everything's all right. Maybe it was just the power glitch that caused this. Flick switch, satisfying lights glow. Reach over for the earphones, get them plugged in—radio goes. That's at least good. Flick the switch back over to tape, press play. Uh oh, nothing happens. Oh, that's right - this wants its lever depress... hang on, it's already depressed from when I screwed in that little screw again. Oh, great. so the original problem is still not fixed.


Undo the first five screws (again), remove back (again), remove only the four screws that actually hold the sides on, because now the base can stay on as I don't need underneath it. Remove the central screw inside, as I need back into the tape mechanism again. Pop off the front, taking that little screw out too... yup. gotta point a little screwdriver at it so I don't lose it. Off with the capstan band, off with the four screws that hold the tape mechanism in place, and I ease it out to have a further look at it. I ease out the tape from the place where it's sitting, press the play head, and it doesn't move. So I press play - the play button depresses and locks satisfyingly. But the head doesn't actuate. Weird. I jiggle it a little, and it flicks, and pops back down into place. Ah, I see. Now it should actuate. Press play, nope. Doesn't actuate. Strange. Jiggle around some more, then realise I have to flip the head around manually anyhow. Do that, then press play. Clunk. The head actuates, finally. Good. Press stop, the head drops back down. I think I'm done here, so I'll wrap up. Put the mechanism back into place, not quite as easily this time, as I have to contend with the base being in place instead of neatly out of the way. Still, I manage it, and put the front back on, remembering to put the little screw back into place to lock that lever down. Put the central screw in to hold the front on, then put the sides on, put the back on, oh, hang on - have to put the aerial back on, so it's off with the sides, on with the aerial connector, then on with the sides, then on with the back. Put a tape into the mechanism, plug in the earphones, plug in the plug into the wall, flick switch, flick power on. Press play, ahh. NOW it works. I even hear sound, though it's .... hang on, it's backwards. Whoops.

Press stop, off with the power, unplug, five screws, four screws, central screw, one tiny screw, front. Remove tape, fiddle with head, flip it around. Tiny front screw back in, central screw, etc etc... only this time I don't put the back on. Just put the tape back in, press play. Yay, now I get sound; though it's a bit muffled, it is recognisable and playing in the right direction. Cool! While the music's playing, I put the sides on, aerial contact didn't come off this time, so it's the back on after the battery contacts go back into place. Plug the power in - yup, still goes, still plays the tape. Good. I'm done.

And then I realise the capstan band is still out on the floor.

Expletive deleted by request of owner

Suffice it to say, that after the job was finished (and after a suitable couple of deliberate drops onto the floor)—yes, that did fix the audio, not muffled now), I'd spent nearly three hours on this simple little tape deck. It now works, thankfully, which means I can plug my MP3 player into it and hear music through the speakers. But boy, was this an adventure I don't wish to repeat.