Repairing old cassette player (Philips N2233)

Discussion in 'The Projects Forum' started by Wave Function, Dec 10, 2014.

  1. Wave Function

    Thread Starter New Member

    Dec 10, 2014
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    Hello, people of this forum! I'm new here!

    I'm in need of help to repair an old cassette player that's been laying in my attic for several years. When you turn it on it seems working and everything; it even plays the cassette quite well (it does play some noise too, but I think it only needs demagnetisation), untill, in just a few seconds, the tape starts tangling up. I tried polishing the heads and yes, they were horribly dirty, but cleaning them up to perfection didn't solve the problem. The "receiving" gear (I hope you get what I mean) won't spin at all when playing the cassette and it will barely catch up when fast forwarding, so I thought it's obvious that there is some problem with its motor. Only, I searched the schematics (http://freeservicemanuals.info/en/servicemanuals/download/Philips/n2233.pdf) and it appears that there is just one motor for both gears. So my question is:
    • Can anyone of you understand if the problem described could be related to the motor? Basically, if it turns out that there is only one motor input, it probably means that it is the mechaninsm transmitting and transforming this input to be malfunctioning.
    • If the motor is the source of the problem, can someone somehow desume the characteristics of this motor from the schematic so that I could replace it?
    • Any other idea about what component could cause the problem? Becouse it really looks electronical rather than mechanical.
    Before I open the case, do something stupid and blow it up, I'd like to have the opinion of an expert.
    Thank You!
     
  2. takao21203

    Distinguished Member

    Apr 28, 2012
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    the rubber belts need to be replaced eventually
     
  3. Wave Function

    Thread Starter New Member

    Dec 10, 2014
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    You mean the pulleys inside? So the pulley that should transmit power to the "receiving" gear is damaged and it doesn't rotate as it should.... Makes sense!
    I'll open that thing up and check if there's some shredded pulley. And my next hot tea will have some orange juice in it. Thanks Takao!

    Meanwhile, a second opinion is more than welcome!
     
  4. takao21203

    Distinguished Member

    Apr 28, 2012
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    some of the moving parts may have rubber coatings or rubber rings and its finicky to disassemble.

    If the tape jumbles its transported, might be the parts which transport the tape.
     
  5. Dodgydave

    Distinguished Member

    Jun 22, 2012
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    you need a belt kit, probably a tyre kit also cleaning fluid.
     
  6. Wave Function

    Thread Starter New Member

    Dec 10, 2014
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    Okay, it might be that the tape is being transported by consumed rubber parts... But what I observe is that one of the gears, the one that should be moving when I press "play", won't spin. If I gently force it to rotate, it vibrates and struggles to spin for an instant, then dies again. This appears to be the major problem.
    So this is likely a matter of mechanisms... It doesn't really relate to electronics. I'm sorry I talked about it on this forum, but I really thought it could have to do with the motor or some driving circuit. But the more I think of it, and the more I test it, the more I'm convinced it has to be caused by some transmission belt (as Dodgydave just said). I can't do it right now, it's getting late, but I'll at least try to solve the problem.

    Thank you all for the help you're giving and again sorry - I have limited knowledge both in english and in electronics/mechanics....
     
  7. takao21203

    Distinguished Member

    Apr 28, 2012
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  8. GopherT

    AAC Fanatic!

    Nov 23, 2012
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    Most of the transport systems did not use ball bearings for fear of audible roller noise. Most just used oil impregnated powdered brass bushings. Over time, long times (like 15 to 40 years), the liquid portions of those lubricating oils evaporate and either result in a dry bushing or leave behind thick waxy solids which provide essentially no lubrication.

    IF you can get that sticky gear off of its axle, spray some solvent-based degreaser in the gear and clean it out. Clean the shaft as well. Let both parts dry well. Then add some thin machine oil (sewing machine-type oil) before re-assembling.
     
  9. Kermit2

    AAC Fanatic!

    Feb 5, 2010
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    the tape transport wheels, the ones that insert themselves into the cassette sprocket openings. check them. often one will have a pressure plate of cork connecting it to the driving gear below. if it is glazed or slick from lubricant it will stop moving or slow and cause tape winding problemd
     
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  10. GopherT

    AAC Fanatic!

    Nov 23, 2012
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    I agree with Kermit. Some 400 grit sandpaper on the glazed rubber or cork transport wheels will help if yu cannot find replacements or if you are only looking at a stop-gap solution. Make sure the part is removed so you don't end up with sandpaper grit or rubber dust in the wheels and head.
     
  11. alfacliff

    Well-Known Member

    Dec 13, 2013
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    kerosene will rejuvinate the rbber parts, the ones that arent actually cracked or broken, use sparingly.
     
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