Many problems of this nature are caused by either the loading belt slipping or tarnished contacts on the microswitches that detect the drawer position.
This might give you some clues:
Sony CDP790 and KSS240 Restoration Project
As to obtaining a complete transport... I think you would be lucky to source such a replacement this far down the line tbh.
This might give you some clues:
Sony CDP790 and KSS240 Restoration Project
As to obtaining a complete transport... I think you would be lucky to source such a replacement this far down the line tbh.
Thank you very much, I made a mistake on the model its Rotel Rcd-991
That transport in your link is the same one!
What is the size of that little belt so I can order one and start over in hoping it might stop ejecting?
According to this list of DAC/transports it would not be the same exact model above but KSS-213B, and you can get them on ebay for less than 10$
I'm afraid I can't remember the exact size now but all is not lost, the drawer should remove easily and allow you to clean the belt as a first step.
A pretty certain test of the belt is to gently impede the tray as it comes out and for you to see if you can detect or hear the drawer motor running. Any slippage should be apparent. Stalling the drawer should stall the motor but only do this momentarily though.
If you pull the drawer in and out by hand (to remove and refit it) then do it slowly because the motor also acts as a generator when turned like this and that feeds voltage back into the circuitry.
Microswitch issues are really common and could be favourite tbh… but check the belt first.
A pretty certain test of the belt is to gently impede the tray as it comes out and for you to see if you can detect or hear the drawer motor running. Any slippage should be apparent. Stalling the drawer should stall the motor but only do this momentarily though.
If you pull the drawer in and out by hand (to remove and refit it) then do it slowly because the motor also acts as a generator when turned like this and that feeds voltage back into the circuitry.
Microswitch issues are really common and could be favourite tbh… but check the belt first.
That belt is pretty beat up, looks like part number Rotel Rcd-991 BELT. LM 3-653-387-(01) but if I figure out the size I can find one maybe on ebay
Thanks!
The belt will have stretched only a little in practice so I would try and measure it. Cotton can be good to lay over the old one and determine the circumference that way.
How much
This isn't the one but as an example of price:
https://cpc.farnell.com/unbranded/belt66/belt-square-28-0x1-2mm-diaxw-av7003/dp/AVBELT66?st=belts
Measure it and see what you can come up with.
How much
This isn't the one but as an example of price:
https://cpc.farnell.com/unbranded/belt66/belt-square-28-0x1-2mm-diaxw-av7003/dp/AVBELT66?st=belts
Measure it and see what you can come up with.
Sorry I don't get your question. What I mean is that, according to that site I linked to, it would not be a KSS-240 but a KSS-213B.
One out of Malaysia for $4The belt will have stretched only a little in practice so I would try and measure it. Cotton can be good to lay over the old one and determine the circumference that way.
How much
This isn't the one but as an example of price:
https://cpc.farnell.com/unbranded/belt66/belt-square-28-0x1-2mm-diaxw-av7003/dp/AVBELT66?st=belts
Measure it and see what you can come up with.
Diameter 28 mm CD DVD Player Tray Belt Rubber Ring | eBay
Here is the schematic diagram: ROTEL RCD-991 SM Service Manual download, schematics, eeprom, repair info for electronics experts. Just wait a minute or so until it says download. At the bottom left corner you will see the in-out signal from the drawer. It is the five pin connector K401 pin 1 and 2, probably from microswitches from the Sony drawer. Pin 4 and 5 is the motor control in and out from IC LB1641. Yes it is limit switches and on page 5 you will see the two leaf switches for in-out on board 51. S151 load out, S152 load in.
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but I really do suspect your problem is most likely microswitch related... which is still an easy fix.I own a RCD 971 model. Its with KSS213 optics and transport. I looked the 991 loader and its a higher grade loader than mine but its mechanically similar. Sometime in the past I faced the same irritating problem of it never fully loading to play but eject in and out. It just won't load up the cd to play position. I found 2 faults, the belt was aged and I couldn't find the same exact diameter but found a more snug fit type that would do as long as its not overly tight. That solved, it worked normally but in the coming months the same fault repeated itself and this player is occasionally used, since I'm more to vinyl than CD.
Belt changed to a new one not too long ago and the fault resurfaced. It didn't make sense. I dismantled the mechanism again and this time I focused on the motor pulley. I found the pulley V groove was too smooth or the plastic property had changed so much so that the belt and pulley was slipping and cannot trigger the motor to cut off when the loader travel is fully in. I carefully roughed up the motor pulley groove with very fine abrasive paper, cleaned it up with alcohol, reassembled and the problem went away. So far so good. There was absolutely nothing wrong with the electronics or control circuitry.
Belt changed to a new one not too long ago and the fault resurfaced. It didn't make sense. I dismantled the mechanism again and this time I focused on the motor pulley. I found the pulley V groove was too smooth or the plastic property had changed so much so that the belt and pulley was slipping and cannot trigger the motor to cut off when the loader travel is fully in. I carefully roughed up the motor pulley groove with very fine abrasive paper, cleaned it up with alcohol, reassembled and the problem went away. So far so good. There was absolutely nothing wrong with the electronics or control circuitry.
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