Nakamichi 480z Rewind Issue Mid Tape

[joolshull20]

Afternoon guys,

Need a bit of guidance with this Nak. New belts, idlers in v good condition.

However, once the tape gets past the halfway point the tape stops automatically, rather like when hitting a memory point. FFW, Play etc all ok. Same any tape.

My question is, are there any adjustments that can affect this, does back tension affect it?

Gone quite a long way with this so far, New ic for meters, dry joints, new fuse holders which were stopping the logic controls working properly and transistor that switches power to capstan motor. Probably doesn’t sound a lot but the fault finding took me some considerable time.

I could really do with some guidance here as I don’t want to start stripping stuff out again needlessly.

Thanks in advance, J

Video here: https://youtube.com/shorts/4CedSQT8Hjs?feature=share

 

[radiokom]

Try another cassette.

 

[joolshull20]

Thank you, but a fairly obvious thing to do. So yes have tried other tapes

 

[radiokom]

Remove front panel and look at lamp under counter. If it does not light, tape motion sensor does not work and deck stops.

 

[joolshull20]

Hi, yes lamp is working, play, ffw work, rw only presents problem when tape is past mid point when rewinding

 

[radiokom]

Well, hard to say by distance. Idler roller arm spring is in place? So, if you push rewind without cassette and rotate take up spindle by hand, supply spindle rotates OK (try to stop with other hand)?

 

[joolshull20]

Remove front panel and look at lamp under counter. If it does not light, tape motion sensor does not work and deck stops.

Update Radiokom, I was aware of the lamp as some are and it is indeed working, however, understandably isn’t as bright as once was. I’ve re-positioned the lamp and all seems good. Thanks for input