Philips EL 3541 Pause Lever Threaded End Function

[DMcMahon]

When the Pause key is a pressed down a long metal lever/rod moves to the right and various things are actuated.

The right hand end of the rod is threaded and when Pause is pressed down the threaded section moves further into the right hand side compartment.

Does anybody know the reason why the end of the lever is threaded, should there be something screwed onto it ?

David

[vidjoman]

You could get a cable operated foot-switch that operated the lever for use as a dictation machine whilst typing.

[Kentode]

David, is there a break in the casting that I've highlighted? If so, would the screwed thread push the casting rather than go past it if it was complete?

Picture to follow, broadband problem!

[Kentode]

Picture...

[vidjoman]

It's a U shaped part of the die cast chassis casting on which the outer end of the cable rests and the rod is pulled by the inner cable fitting that has a threaded insert.
I think the cable type is called a 'Bowden Cable' and similar to brake cables on a bicycle.

[Sideband]

Originally Posted by vidjoman

You could get a cable operated foot-switch that operated the lever for use as a dictation machine whilst typing.

Yes that is exactly correct. I only ever saw one of these foot levers when I was at Philips. It was a very long time ago! The machines were nearing the end of their service life when I started in 1973 but the odd one still came in for service. That was the only time I ever saw one with a foot-lever.

Proper dictation machines were available but very much more expensive of course.

[Sideband]

Originally Posted by vidjoman

I think the cable type is called a 'Bowden Cable' and similar to brake cables on a bicycle.

That's exactly what it was, just a bowden cable operated by a foot-lever. Purely mechanical. Very crude but it worked.

[DMcMahon]

Originally Posted by vidjoman

You could get a cable operated foot-switch that operated the lever for use as a dictation machine whilst typing.

Thankyou that is interesting and now makes sense.

This very minute I have also read about it in the EL 3541 Operating Instructions manual, which includes a small drawing showing it connected. The foot switch is listed as EL 3984/15.

David

[DMcMahon]

Originally Posted by Kentode

David, is there a break in the casting that I've highlighted? If so, would the screwed thread push the casting rather than go past it if it was complete?

Picture to follow, broadband problem!

Ken mine is as per your photo, I am unsure what you mean by "push the casting".

David

[Kentode]

Originally Posted by DMcMahon

Ken mine is as per your photo, I am unsure what you mean by "push the casting".

David

My mistake David, from the picture l thought perhaps the part I've described as a casting was something like a blind threaded nut which had split. My picture is a closeup of yours.

Hope that makes sense...

[Refugee]

I have got a 3553 and it also has the pause rod on it.
Getting the cable these days would be so difficult that it might be easier to make up a radio controlled servo to operate it.
There was a lot of goo to clean up on it. Both the clutches and the belts had turned.

[DMcMahon]

Think I have been lucky with this one, looks pretty good condition and belts look good, not sure about the clutches, yet to power it up.

David

[DMcMahon]

Originally Posted by Kentode

My mistake David, from the picture l thought perhaps the part I've described as a casting was something like a blind threaded nut which had split. My picture is a closeup of yours.

Hope that makes sense...

Yes all clear now Ken.

David

[ricard]

Several Philips machines of the period had this remote control facility. I've seen it on the 1962 EL3547 as well. It was probably very cheap to implement, as all that was needed was the extension of a rod that was already necessary in the mechanical design.

[ben]

If I had a spare solenoid, I'd convert that to an electronic stop! Some Philips units had foil end stop too, does this model? I know they skipped it the N4307/4308 successors.

[DMcMahon]

From a quick look at the schematic and the unit it looks like the EL 3541 does not have end of tape foil detection.

David

[ricard]

Yep, it doesn't, although it's larger brother the EL3542 (and related siblings) does.

[TonyDuell]

In a lot of machines (all of them?), the foil-triggered autostop solenoid simply acts like the stop (not pause) key and releases the other keys. It will not restart the machine when you de-energise it.

The pause control of course lifts the pinch roller and brakes the takeup spool. Releasing it will restart the tape.

Bowden cables are not hard to get, for bicycles if nothing else. I would have thought making the end fitting to go into the tape recorder was a fairly simple turning job. Does anyone have a photo of that end of the thing?

[DMcMahon]

Sketch from the EL 3541 Operating instructions.

David