Servicing a SONY DAT machine (Pictorial)
- Thread starter SaSi
- Start date
The problem usually lies in the part circled in red.
It is a kind of silver metal hook that should freely slide along one of the large black gear.
Most of the time it is stuck due to old grease, thus the right guide reaching its end position too soon, preventing the left guide to achieve its travel as it should.
It is a kind of silver metal hook that should freely slide along one of the large black gear.
Most of the time it is stuck due to old grease, thus the right guide reaching its end position too soon, preventing the left guide to achieve its travel as it should.
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thanks for this! My concern is my ability to take apart and reassemble the mechanism correctly; this does not look like a straightforward task! is there a tutorial in this thread or somewhere?
Does is it seem correct to you that hardened grease could cause the problem i have -- deck will 100% refuse to give audio playback on pressing PLAY unless i tap FFW a few times. It also records correctly. For these reasons i have doubts that the issue is mechanical not electronic?
Does is it seem correct to you that hardened grease could cause the problem i have -- deck will 100% refuse to give audio playback on pressing PLAY unless i tap FFW a few times. It also records correctly. For these reasons i have doubts that the issue is mechanical not electronic?
do you mean 'up' into the catcher? if so, no, it seems solidly in place like the right one. Or do you mean does it have play on its post? i will double check. I have tried to gently move/manipulate both l and r guides during playback but it doesn't trigger any hint of audio/signs of life on the meters. only if tap FFW (or RW) on and off does it make playback kick in. strange.
Yes, "up" into the catcher.
In post #1438, you wrote : update so far: if i get the deck to produce DAT tape audio by hitting FFW quickly AND it arrives at the point where it starts to distort -- if at that point i lightly press on the end of post 203 it makes the distortion go away.
This point is crucial as it is the main know default of this transport, along with the posts freely rotating in their socket.
Beside all that, a good cleaning of the drum is a prerequisite.
In post #1438, you wrote : update so far: if i get the deck to produce DAT tape audio by hitting FFW quickly AND it arrives at the point where it starts to distort -- if at that point i lightly press on the end of post 203 it makes the distortion go away.
This point is crucial as it is the main know default of this transport, along with the posts freely rotating in their socket.
Beside all that, a good cleaning of the drum is a prerequisite.
Hello, I'm fixing my DTC-1000ES mechanism and have cleaned the rotary encoder contacts, aligned the gear as per the service manual instruction and wheeled the pinch roller arm up to the shaft to about half a millimeter close.
When powering on, I notice the pinch roller arm going down, the two tape threading arms in a V shaped groove also going down.
My problem is all three of these arms only travel about 2 centimeters at a time and then stop with the caution message then displaying.
I can power up several times to confirm the pinch and threading rollers move completely down to the end of their position, but nothing happens after this as I expect the tape loading mechanism to begin some kind of movement (tape presence detectors pressed).
The three tape mech gears and their shafts where cleaned and regreased though I'm not too happy about their condition.
The tape mech has a new belt and doesn't spin loose, the loading mech has a used belt that is still tight enough in my opinion.
Any idea about where to take it from here ?
Thanks
When powering on, I notice the pinch roller arm going down, the two tape threading arms in a V shaped groove also going down.
My problem is all three of these arms only travel about 2 centimeters at a time and then stop with the caution message then displaying.
I can power up several times to confirm the pinch and threading rollers move completely down to the end of their position, but nothing happens after this as I expect the tape loading mechanism to begin some kind of movement (tape presence detectors pressed).
The three tape mech gears and their shafts where cleaned and regreased though I'm not too happy about their condition.
The tape mech has a new belt and doesn't spin loose, the loading mech has a used belt that is still tight enough in my opinion.
Any idea about where to take it from here ?
Thanks
herfurthba
New Member
Hi. If the threading rings, arms and gears have been cleaned and carefully regreased and the belt is good it only depends on timing:
I assume the threading rings are aligned by putting a thin screwdriver through both of them and the hole in the chassis below that position? Good. Then put in the gears and assemble the rest.
No turn the beast around and spin the pulleys with the belt that drive the loading mecha and ensure both loading guides move towards the head drum and reach their stoppers about same time. On the last portion of that movement the pinch roller arm starts to move towards the capstan.
If all move freely and in sync move the mech until the pinch roller reaches the top bearing tower of the capstan - not the capstan itself and 1mm to capstan is way too close.
The top of the capstan housing that is farest from the capstan and the outer end of the pinch roller's rubber need to be aligned.
At that position the rotary encoder needs to be assembled in its mid position with the mark and line aligned.
Then power up and the threading arms move down. Insert a tape and check. Fine tuning can be done by turning the rotary encoder in its long holes.
I assume the threading rings are aligned by putting a thin screwdriver through both of them and the hole in the chassis below that position? Good. Then put in the gears and assemble the rest.
No turn the beast around and spin the pulleys with the belt that drive the loading mecha and ensure both loading guides move towards the head drum and reach their stoppers about same time. On the last portion of that movement the pinch roller arm starts to move towards the capstan.
If all move freely and in sync move the mech until the pinch roller reaches the top bearing tower of the capstan - not the capstan itself and 1mm to capstan is way too close.
The top of the capstan housing that is farest from the capstan and the outer end of the pinch roller's rubber need to be aligned.
At that position the rotary encoder needs to be assembled in its mid position with the mark and line aligned.
Then power up and the threading arms move down. Insert a tape and check. Fine tuning can be done by turning the rotary encoder in its long holes.
How long does it take to travel 2cm ?
I believe that there is a timing check to prevent damages if the loading / unloading sequence takes too long. The DTC-55ES has such a feature.
eugenro2001
New Member
Hello
I have a problem with a DTC-57.
It doesn't have audio, the level meters don't show anything and it doesn't read the absolute time.
It worked fine and now don't.
The problem started after I tried to record something. After that it played ok for a few times, now doesn't play at all.
The RF amp is ok, I works ok on another deck and the RF amp from that deck makes no difference on 57.
The 57 is in very good condition, very clean, even the cleaning sponge is in good shape.
I checked the main board for bad soldering, all is good.
I have no ideea where to look.
Any help greatly appreciated.
I have a problem with a DTC-57.
It doesn't have audio, the level meters don't show anything and it doesn't read the absolute time.
It worked fine and now don't.
The problem started after I tried to record something. After that it played ok for a few times, now doesn't play at all.
The RF amp is ok, I works ok on another deck and the RF amp from that deck makes no difference on 57.
The 57 is in very good condition, very clean, even the cleaning sponge is in good shape.
I checked the main board for bad soldering, all is good.
I have no ideea where to look.
Any help greatly appreciated.
eugenro2001
New Member
Thank you for your reply.
They looks fine. I will resolder, maybe will be lucky.
I also checked the voltage on the rf amp connector, is ok.
They looks fine. I will resolder, maybe will be lucky.
I also checked the voltage on the rf amp connector, is ok.
vallentin
New Member
-Get rid of the sponge - even if you think is in good shape, all it does now is contaminate your drum heads.
-Thoroughly clean the heads using the paper method and isopropyl. Also clean all the guides and tape path, pressure roller and the outside of the drum.
-Check continuity from CN501 (back of the main board) to CN51 (back of the RF Amp). Resolder if needed, as @hdrobien said.
Bear in mind that lead free solder is never to be trusted in these old devices.
As a precaution, I usually resolder every connector with lead solder. Also, every mechanically stressed points. Like IC901 and IC902 from Power board, input and output connectors, etc.
-Check RF signal with the scope and go from there.
-Thoroughly clean the heads using the paper method and isopropyl. Also clean all the guides and tape path, pressure roller and the outside of the drum.
-Check continuity from CN501 (back of the main board) to CN51 (back of the RF Amp). Resolder if needed, as @hdrobien said.
Bear in mind that lead free solder is never to be trusted in these old devices.
As a precaution, I usually resolder every connector with lead solder. Also, every mechanically stressed points. Like IC901 and IC902 from Power board, input and output connectors, etc.
-Check RF signal with the scope and go from there.
Have you actually looked at the eye pattern coming in from the heads on the RF test point to make sure it's linear and uniform with respect to the tape itself?