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 > General Vintage Technology > General Vintage Technology Discussions

Notices

General Vintage Technology Discussions For general discussions about vintage radio and other vintage electronics etc.

Reply
 
Thread Tools
Old 24th Nov 2022, 5:38 pm   #21
HamishBoxer
Dekatron
 
HamishBoxer's Avatar
 
Join Date: Aug 2007
Location: W.Butterwick, near Doncaster UK.
Posts: 8,601
Default Re: 100 years of BBC

The "Knife Switch" looked like a knife blade and was ceramic base and used to earth aerials in thunderstorms etc.

Of course some were indeed used to switch power, a bit lethal depending on voltage across it!
__________________
G8JET BVWS Archivist and Member V.M.A.R.S
HamishBoxer is offline   Reply With Quote
Old 24th Nov 2022, 5:51 pm   #22
G6Tanuki
Dekatron
 
G6Tanuki's Avatar
 
Join Date: Apr 2012
Location: Wiltshire, UK.
Posts: 11,876
Default Re: 100 years of BBC

Yes, the usual Knife-switch was a ceramic- or Bakelite-based beastie, looking like a miniature version of what you might see in Dr. Frankenstein's Laboratory.

"More Power, Igor!! More Power!!"

There were 2 kinds - one a simple 1-way version, you wired the antenna to one side and the other side to earth, so when the switch was closed they were shorted together and any static charges picked up by the antenna were drained away to earth.

The other kind was a 2-way switch; you connected the antenna to the centre, then one of the outer terminals went to the radio, the other to earth.

You had to remember to throw the switch.... not much good if you usually had it in 'radio' mode and the thunderstorm arrived while you were out at work!


Attached photo shows the second type.
Attached Thumbnails
Click image for larger version

Name:	DSC04200_grande.JPG
Views:	72
Size:	35.6 KB
ID:	268662  
__________________
"Fast, Reliable, Cheap, Easy-to-use. Choose any two". -Boardwatch, Sept 1991
G6Tanuki is online now   Reply With Quote
Old 24th Nov 2022, 8:57 pm   #23
Radio Wrangler
Moderator
 
Radio Wrangler's Avatar
 
Join Date: Mar 2012
Location: Fife, Scotland, UK.
Posts: 20,569
Default Re: 100 years of BBC

note the asymmetric clearance distances of the switch in the photo above.

Radio goes to the left, Earth to the right. antenna to the centre.

David
__________________
Can't afford the volcanic island yet, but the plans for my monorail and the goons' uniforms are done
Radio Wrangler is offline   Reply With Quote
Reply

Thread Tools



All times are GMT. The time now is 8:48 pm.


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 - 2022, vBulletin Solutions, Inc.
Copyright ©2002 - 2021, Paul Stenning.