DEC pictorgram - right pointing arrow going into circle

[leegleason]

I was looking at some distribution panels today. Things are often identified by pictograms on these - a big oval for a monitor, a stylized mouse or keyboard for a mouse or keyboard, and like that I noticed one that I didn't recognize. It's a right pointing arrow going into a circle. Anyone know what that symbol stands for?

 

[krebizfan]

On which DEC machine? I seem to remember that as being used to signify audio input before the circle got split into 3 concentric partial circles on later machines but I don't remember how closely DEC followed the symbols used by competitors.

 

[leegleason]

It was on a distribution panel for a VCB01 on a VAXstation 1. It also appears on VCB02 distribution panels. Here's an example

 

[leegleason]

I don't think it's audio in - VCB01s and VCB02s don't have any audio capability.

 

[NeXT]

That would be to indicate that port was for the video display, plus the keyboard and User Input Device, such as the puck mouse they were selling at the time.
Notice on the connector on this photo the same symbol.

 

[leegleason]

Thanks, that makes sense. That didn't occur to me, since the distribution panel for the VCB01 (the one I picture is VCB02) has a separate port with a more obvious mouse pictogram, as well as the arrow and circle. But, in that case, it probably means the tablet and crosshairs device that was also available, that is also a pointing device.