UK Vintage Radio Repair and Restoration Powered By Google Custom Search Vintage Radio and TV Service Data

Go Back   UK Vintage Radio Repair and Restoration Discussion Forum > Specific Vintage Equipment > Vintage Television and Video

Notices

Vintage Television and Video Vintage television and video equipment, programmes, VCRs etc.

Reply
 
Thread Tools
Old 14th May 2021, 5:36 pm   #1
Stockden
Heptode
 
Join Date: Mar 2008
Location: Forest of Dean, Gloucestershire, UK.
Posts: 545
Default Vision mixer type 261 - what does "Emergency" do?

For reasons best know to it's algorithm Amazon video suggested I watch "A Hard Days Night" recently. It must be over 45 years since I last saw that film so, ever a sucker for nostalgia, I had a look.

Perhaps unsurprisingly (and despite not having a broadcast or video background) I found myself paying much more attention to the TV studio scenes and equipment than I ever would have done as a teenager. One of the things that caught my eye was the prominent "Emergency" bar at the top of the EMI type 261 vision mixer that was visible in several shots.

So, purely out of curiosity, what did that do? Was it a common feature of vision mixers at the time and is it so today?
Attached Thumbnails
Click image for larger version

Name:	vision mixer 261.jpg
Views:	97
Size:	39.5 KB
ID:	234032  
Stockden is offline   Reply With Quote
Old 14th May 2021, 6:08 pm   #2
PaulM
Hexode
 
Join Date: Nov 2006
Location: Near Lincoln, UK.
Posts: 377
Default Re: Vision mixer type 261 - what does "Emergency" do?

The 'emergency' is failure of major video systems.
It's a simple cut bus between sources which bypasses anything in the mixer which is complicated and has gone wrong.

A normal feature at the time, although designs varied, but it was often just a bunch of relays (or simple switches) hard switching the incoming video which may go right back to the sources (cameras etc.) taking out another level of possible trouble in distribution amplifiers and sub-systems.

Nothing complicated or sinister - just a fix in case of electronic and/or wiring failure to 'keep the show on the road'.

The one in the picture is under a lift-up flap to prevent accidental operation.

Not really needed today and difficult to do in a software controlled environment, but I think it's usually still an option (of sorts).

Best regards,

Paul M

Last edited by PaulM; 14th May 2021 at 6:15 pm.
PaulM is offline   Reply With Quote
Old 14th May 2021, 6:35 pm   #3
Stockden
Heptode
 
Join Date: Mar 2008
Location: Forest of Dean, Gloucestershire, UK.
Posts: 545
Default Re: Vision mixer type 261 - what does "Emergency" do?

Thanks Paul. I suspected that the emergency in question would be an equipment failure (rather than, say, a fire in the studio) but it's nice to know exactly what it did.

Hugh
Stockden is offline   Reply With Quote
Reply

Thread Tools



All times are GMT. The time now is 2:35 am.


All information and advice on this forum is subject to the WARNING AND DISCLAIMER located at https://www.vintage-radio.net/rules.html.
Failure to heed this warning may result in death or serious injury to yourself and/or others.


Powered by vBulletin®
Copyright ©2000 - 2021, vBulletin Solutions, Inc.
Copyright ©2002 - 2021, Paul Stenning.