Old style tape recorder

[Barquentine]

Does anyone know how to fix the autostop mechanism on an oldstyle piano key tape recorder? It keeps cutting out after a few seconds & I understand this is a common problem.

[gen2]

Wow! That takes me back a few years (and more)!
Are you talking cassette type or reel-to-reel here? The following answer applies to reel-to-reel.

If I remember rightly, there is a spring-loaded capstan that the tape passes round and if there is any drag on the feeding spool, the capstan is pulled across and activates the stop mechanism.

If your machine is cutting off after a few seconds, then there must be an excess load/drag caused by the feed spool. Check that it is turning freely and lubricate if necessary.

If you are able to feed the tape through by-passing the tensioned capstan, then the tape will play, but the extra drag may cause it to be slowed and consequently lower the tone of what is being played. The other danger is when the tape reaches the end - it won't cut out so will excert undue tension on the tape that may stretch it or snap it (apart from possible damage to the machine).


If you are using a cassette type machine, then the excess drag is likely to be caused by uneven laying of the tape around the spindle within the cassette. I suggest fast winding right to the end and then fast rewinding back to the start before trying again. That should lay the tape more evenly.

[Barquentine]

Thanks for that. It is a cassette type - and it cuts out on fast forward (and I think on rewind too) as well. I'm hopeful this is a simple thing to fix since it's hard to find anyone to repair these things these days.

[pug100]

Probably the reason nobody will repair them is that a new one costs just �15 from Maplins

http://www.maplin.co.uk/Search.aspx?criteria=t ape%20recorder&source=15&SD=Y

Or a Sony one from Argos �25

http://www.argos.co.uk/webapp/wcs/stores/servl et/Search?storeId=10001&catalogId=1500001001&l angId=-1&searchTerms=SONY+TCM939

[Barquentine]

This one is part of an antique Dynatron music centre so it would be good to get it all working again.

[Mortartube]

There is usually a small plastic pin that protrudes (often white in colour), this is the tape stop switch. Basically the idea is that the motor pulling a tape that has ended, will add just that little bit more tension and pull the tape tighter than when it is running. The tape touches the pin a little and pushes it in activating the switch. It may be the stop switch or it may be general wear meaning the cassette mechanism no longer operates to the original tolerances.If it is overall wear, ther's not a lot you can do. I would think Maplins, RS components or CPC may still hold stock of the tape stop switches. I think they were fairly standard in design.

[romko]

you need to post on uk vintage repair restoration forum. lots of good folk there who know about this stuff, dynatron is a common name there!

having fixed a number of these, chances are, there is a slack drive belt not turning a sensor and the machine thinks it is at the end of the tape - thus activating the autostop.

[beso]

Mortartube describes the most common autostop mechanism. Most often the problem is excessive drag in the take off spool. This has a clutch tensioned by a spring behind it. You can sometimes see the spring.

If something gets wound around this area it may jamb the clutch.

If all seems clear then you need to dismantle the clutch and clean it. There is usually a tiny c-clip in the middle.

Otherwise the spring on the autostop mechanism itself may be weakened allowing it to be engaged too easily. It is usually located just before the capstan pinch roller.

Press the play button with the door open. Then press on the autostop and see if it offers any resistance at all. If it triggers at the slightest touch then this is the problem.