Servicing a SONY DAT machine (Pictorial)
- Thread starter SaSi
- Start date
You have to reposition the white cog.
If you look at the pictures you will notice that each cog has a dent larger than the others. This larger dent must fit in the space on the dented bridge.
To replace a clip you can cut a thin "slice" in the insulator of a electric wire (rigid if possible). It will look like a ring.
If you look at the pictures you will notice that each cog has a dent larger than the others. This larger dent must fit in the space on the dented bridge.
To replace a clip you can cut a thin "slice" in the insulator of a electric wire (rigid if possible). It will look like a ring.
That's a great idea :thmbsp:
ah nah, no it was the right way. I guess the spring had been off the tension for so long it got looser round the screw meaning it couldn't stretch enough to reach the plastic pip. The metal of the spring was quite strong. Sadly, I thought it would be a good idea to try and make it 1 less wrap around the screw and the glue came off the other end meaning it had fallen off. So (now I'm waffling here a bit) I thought I'd just straighten it out and start again with it later on re-glueing it back on, but sadly I used the wrong tools I thought I was using a pair of plyers but they were actually cutters and I cut the spring! doh!
So I checked to see if this door actually mattered, I guess it keeps dust out but apart from that not much. It doesn't touch any microswitches so I thought I'd bodge it with a spare belt I had kicking about up there and wrapped it round and to my lucky it didn't get in the way and it sort of works!! I'll post a picture in the sec - but really, I'd like to fix it properly long term with a replacement spring.
ANYWAY! after cleaning the capstan and head. and re-recording a long drone from a kids keyboard into the DTC. There were no glitches so it looks like I've done an ok job so far (touch wood!) goodness knows how much hell it could be if I had to do all that tape alignment business with the 2 guides.
Looks like swabs and isopropanol is all you need. Still waiting for a new pinchroller for added faith in this machine.
So that's the good news, the bad news is, my old recording of old songs is in a digital-glitch & drop out frenzy. RIP old recording
luckly I backed it up onto trusy cassette before it got really bad but anyway I'm going off topic here.
Thanks Sasi for your great tutorial! I prety much did all what you explained apart from the bit where you went into schematics for the PCB. That's a step beyond what I can do!
So I checked to see if this door actually mattered, I guess it keeps dust out but apart from that not much. It doesn't touch any microswitches so I thought I'd bodge it with a spare belt I had kicking about up there and wrapped it round and to my lucky it didn't get in the way and it sort of works!! I'll post a picture in the sec - but really, I'd like to fix it properly long term with a replacement spring.
ANYWAY! after cleaning the capstan and head. and re-recording a long drone from a kids keyboard into the DTC. There were no glitches so it looks like I've done an ok job so far (touch wood!) goodness knows how much hell it could be if I had to do all that tape alignment business with the 2 guides.
Looks like swabs and isopropanol is all you need. Still waiting for a new pinchroller for added faith in this machine.
So that's the good news, the bad news is, my old recording of old songs is in a digital-glitch & drop out frenzy. RIP old recording
luckly I backed it up onto trusy cassette before it got really bad but anyway I'm going off topic here.
Thanks Sasi for your great tutorial! I prety much did all what you explained apart from the bit where you went into schematics for the PCB. That's a step beyond what I can do!
Ok before I go, one thing I noticed is, as I was playing the dat back (with lid off obviously) I couldnt help but notice (even without magnifiing tools) little dots or dents at the bottom of the tape every inch or so. Is this normal? Was both on the duff recording part and the new sucsessful recording part.
As your old recordings are supposedly recorded on a properly aligned DAT having glitch and drop could mean that your deck is misaligned.
The new recordings play fine beccause they are recorded/played with the same misalignment.
Could you post a picture of the little dots or dents ?
The new recordings play fine beccause they are recorded/played with the same misalignment.
Could you post a picture of the little dots or dents ?
yeah i'll post some pics, I'll have to open it again anyway as the glitching has come back :tears::tears::tears:
doesn't make sense, glitching on new recordings. Not as much as there used to be but really, I'd like none. I see the tape is not being pulled smoothly by the take-up spool again, I think it might be something to do with those brakes pushed up too hard on the spool :scratch2:
doesn't make sense, glitching on new recordings. Not as much as there used to be but really, I'd like none. I see the tape is not being pulled smoothly by the take-up spool again, I think it might be something to do with those brakes pushed up too hard on the spool :scratch2:
Don't dispair. If I started quoting the times I failed and did stupid things, I'd never finish. The fun is in tinkering. When you get it right, you'll feel a sense of acomplishment.
One idea:
Since the tape extension arm was out of place, it might have been stressed and mis-aligned. If one of the arms is not in alignment, then the trace on the tape can cause misreads.
Another idea:
If the tape is not pristine clean, it may cause dropouts or bad tape-head contact. Such things can cause intermittent squeaks during playback.
Aligning the S/T arms is not an easy task, especially without a known good tape and proper tools. Cleaning the heads is the place to start.
rosh1
New Member
PCM 2800 display spares?
Im back again, just got a Sony PCM 2800 4 head DAT deck from eBay recently.
Plays and records well but noticed that Fluorescent display is very dim. All the segments light up though..
Can this be a problem with a failing FD? Or any other driver etc I should first check. If its a FD issue, anyone know of a good source for spares? The service manual lists it as FL701 no idea about the exact part number
Also would like to try getting a pinch roller or two for the future..
thanks in advance for any pointers!
Rosh
Im back again, just got a Sony PCM 2800 4 head DAT deck from eBay recently.
Plays and records well but noticed that Fluorescent display is very dim. All the segments light up though..
Can this be a problem with a failing FD? Or any other driver etc I should first check. If its a FD issue, anyone know of a good source for spares? The service manual lists it as FL701 no idea about the exact part number
Also would like to try getting a pinch roller or two for the future..
thanks in advance for any pointers!
Rosh
Hello,
I have a DTC-690 with the same problem. I have clean up the heads and it seems that those clicks are now less often.
Do you find the problem in RF circuit?
Regards
Hi there! This thread has indeed became a valuable tool for us poor old romantics trying to keep their Sony DATs up and running.
Personally, I've been fortunate enough to obtain quite a few pro DAT machines, as they are practically given away by larger broadcasting companies. So I have a nice Sony PCM-7040, Fostex D-25, a bunch of Panasonics and so on. But what brought me here were two Sony PCM-2700s that were not working after sitting a while in the storage.
The Sony PCM-2700 is supposedly a pro version of DTC-77ES. It's an ugly, heavy thing with copper-plated chassis and two transformers. When I tested mine, the other one loaded the cassette but the playback was mainly digital distortion - you could tell what was playing, but that's it. The other one needed a new belt for loading mechanism to even suck the cassette in. After that, it sounded the same as the other one.
I did clean the heads, but it didn't help. So I started looking for hints, and came across this thread. Now, the mechanism in 2700 isn't exactly like the one presented by SaSi, but it has many similar parts. The discussion pointed out that Sony tape guides tend to need service. And indeed: the little thingies that are supposed to wrap the tape around the drum didn't quite finish their travel. To be exact, the left one was left a few mm behind the stopper. I pulled it gently during playback (with a cotton swab), and hey presto: distortion-free music!
Now, this thread taught me also that Sony lubricants are less than eternal. So I removed the mechanism as well as the PCB covering the bottom of it and cleaned the path of the loading arms with alcohol. Then I sparingly added new lubricant with a q-tip (high quality synthetic vaseline). I also took the rubber belt operating the loading arms and treated it with rubber rejuvenation stuff, and cleaned & lubricated most of the gears. After reassembly, I inserted a blank cassette and did some 20 load-eject cycles to break the mechanism in.
After loading an actual cassette, I noticed that the mechanical resistance of the tape had some effect on the loading arm travel. However, the repair proved successful, and my Sony now happily plays whatever I throw at it. In more severe cases, I suppose more dismantling and perhaps a new belt are necessary, but this did the trick this time. Hope this might be of help for someone with similar problem.
Take care, and keep vintage equipment going!
Personally, I've been fortunate enough to obtain quite a few pro DAT machines, as they are practically given away by larger broadcasting companies. So I have a nice Sony PCM-7040, Fostex D-25, a bunch of Panasonics and so on. But what brought me here were two Sony PCM-2700s that were not working after sitting a while in the storage.
The Sony PCM-2700 is supposedly a pro version of DTC-77ES. It's an ugly, heavy thing with copper-plated chassis and two transformers. When I tested mine, the other one loaded the cassette but the playback was mainly digital distortion - you could tell what was playing, but that's it. The other one needed a new belt for loading mechanism to even suck the cassette in. After that, it sounded the same as the other one.
I did clean the heads, but it didn't help. So I started looking for hints, and came across this thread. Now, the mechanism in 2700 isn't exactly like the one presented by SaSi, but it has many similar parts. The discussion pointed out that Sony tape guides tend to need service. And indeed: the little thingies that are supposed to wrap the tape around the drum didn't quite finish their travel. To be exact, the left one was left a few mm behind the stopper. I pulled it gently during playback (with a cotton swab), and hey presto: distortion-free music!
Now, this thread taught me also that Sony lubricants are less than eternal. So I removed the mechanism as well as the PCB covering the bottom of it and cleaned the path of the loading arms with alcohol. Then I sparingly added new lubricant with a q-tip (high quality synthetic vaseline). I also took the rubber belt operating the loading arms and treated it with rubber rejuvenation stuff, and cleaned & lubricated most of the gears. After reassembly, I inserted a blank cassette and did some 20 load-eject cycles to break the mechanism in.
After loading an actual cassette, I noticed that the mechanical resistance of the tape had some effect on the loading arm travel. However, the repair proved successful, and my Sony now happily plays whatever I throw at it. In more severe cases, I suppose more dismantling and perhaps a new belt are necessary, but this did the trick this time. Hope this might be of help for someone with similar problem.
Take care, and keep vintage equipment going!
Drifting
Well-Known Member
Thanks a lot for this information. Can I just say that it is not strictly necessary to remove the sides of the mechanism before dismantling it. If you don't remove the sides, it saves a lot of trouble when you come to reinstall it, as you don't have to fiddle around aligning the tape housing to the tape load mechanism attached to the side.
Ok I'm having troubles again with my 60ES. It's the take up reel just stopping and the tape is all collecting in that area of the dat-tape and causing it to 1: digital noise and 2: it powers off the entire deck :thumbsdn:
I'll take it apart again to show you again. I could post up a video of it if you want as you can see it through the window.
I'll take it apart again to show you again. I could post up a video of it if you want as you can see it through the window.
I'm not sure about the mechanism in the 60ES but if it's like the others, then my first guess would be worn pressure pads turned sticky.
Right, so it's apart again.
regarding this bit...
well I've recorded a video because I'm not sure if this is good or bad.
http://www.youtube.com/watch?v=BC74Km5144w&feature=youtu.be
the pinchroller is not in contact with the CS at all! infact it's like 1/4 of an inch :sigh: Is that telling me all this time the tape was being pulled along by the takeup reel. I really hope not.
I could of kept rolling that cog with my thumb but the guides had reached the end of their track and I wasn't sure if I was going to break something so I stopped.
regarding this bit...
well I've recorded a video because I'm not sure if this is good or bad.
http://www.youtube.com/watch?v=BC74Km5144w&feature=youtu.be
the pinchroller is not in contact with the CS at all! infact it's like 1/4 of an inch :sigh: Is that telling me all this time the tape was being pulled along by the takeup reel. I really hope not.
I could of kept rolling that cog with my thumb but the guides had reached the end of their track and I wasn't sure if I was going to break something so I stopped.
