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

Go Back   UK Vintage Radio Repair and Restoration Discussion Forum > General Vintage Technology > Components and Circuits

Notices

Components and Circuits For discussions about component types, alternatives and availability, circuit configurations and modifications etc. Discussions here should be of a general nature and not about specific sets.

Reply
 
Thread Tools
Old 17th Sep 2018, 6:37 pm   #21
ColinTheAmpMan1
Heptode
 
ColinTheAmpMan1's Avatar
 
Join Date: Jan 2012
Location: Wimbledon, London, UK.
Posts: 746
Default Re: What's this? A quiz.

Quote:
Originally Posted by Kentode View Post
Now I've got to research "the wigwam that winds the sun up"!

An advertising slogan?
This was a phrase used by the father of a school-friend many years ago. He was an engineer and used it for anything that he couldn't recognise the purpose of. Does that solve it?
Colin.
ColinTheAmpMan1 is offline   Reply With Quote
Old 17th Sep 2018, 6:47 pm   #22
kalee20
Dekatron
 
Join Date: Feb 2007
Location: Lynton, N. Devon, UK.
Posts: 4,517
Default Re: What's this? A quiz.

Quote:
Originally Posted by Restoration73 View Post
Many of the early GB (Gaumont British, later Rank) Equipments 16mm film projectors
used a 120v lamp, and an external dropper was required. I think the early projectors
were actually Bell & Howell made in the USA.
It's appallingly inefficient, but it does mean the lamp has good protection against switch-on surges, so life can be quite long, almost to the point where light output is falling because of blackening inside the bulb before the filament breaks.
kalee20 is offline   Reply With Quote
Old 17th Sep 2018, 6:57 pm   #23
Boater Sam
Dekatron
 
Boater Sam's Avatar
 
Join Date: Dec 2013
Location: Middlewich, Cheshire, UK. & Winter in the Philippines.
Posts: 3,401
Default Re: What's this? A quiz.

I had one as a kid!
__________________
Boater Sam.
BVWS Member
Boater Sam is offline   Reply With Quote
Old 17th Sep 2018, 7:44 pm   #24
Kentode
Pentode
 
Kentode's Avatar
 
Join Date: Mar 2015
Location: Todmorden, West Yorkshire, UK.
Posts: 219
Default Re: What's this? A quiz.

One what Sam? The dropper? What did you use it for?

The "whim-wham" was a parents answer to the annoying child's questions! As in "Go and play with the traffic", one of my father's favourite ways of letting me know he was busy.
__________________
Regards, Ken.

BVWS member
Kentode is offline   Reply With Quote
Old 17th Sep 2018, 7:44 pm   #25
Lucien Nunes
Octode
 
Lucien Nunes's Avatar
 
Join Date: Apr 2008
Location: London, UK.
Posts: 1,595
Default Re: What's this? A quiz.

Many home projectors, especially 8 & 9.5mm, had resistive voltage droppers. A lower voltage lamp has a shorter, thicker filament which in the lower power ranges e.g. 50W has a real impact on life and luminous efficacy as it can be run hotter / brighter/ whiter and focus better, yet still last longer than a 240V lamp. The power lost in the resistance was only a minor nuisance in the grand scheme of things. Most of these were showing films of tens or low hundreds of feet at a time, so not on for all that long. Some did have transformers for the lamp, but as the motors were often universal, the transformer restricted an inherently AC/DC machine to AC only.

Before the advent of halogen projection lamps, professional / commercial 16mm projectors for AC only often used 115V lamps run from an external transformer. In fact the whole projector was often 115V including motor and amplifier. For DC service where the mains was not 115V, a 230V lamp did away with the need for a huge resistance but at the expense of fragility. Many later substandard projectors for AC only used 12/24V lamps up to 250W run from a transformer, or a secondary on the induction motor winding.
__________________
Three anodes good, six anodes better!

Last edited by Lucien Nunes; 17th Sep 2018 at 7:49 pm.
Lucien Nunes is offline   Reply With Quote
Old 17th Sep 2018, 7:50 pm   #26
Kentode
Pentode
 
Kentode's Avatar
 
Join Date: Mar 2015
Location: Todmorden, West Yorkshire, UK.
Posts: 219
Default Re: What's this? A quiz.

Thanks for the information Lucien, so it might be good for 50 Watts, that's handy.

I'll post the outcome of my experience with it, especially the heat dissipation.
__________________
Regards, Ken.

BVWS member
Kentode is offline   Reply With Quote
Old 17th Sep 2018, 9:36 pm   #27
MotorBikeLes
Octode
 
Join Date: Dec 2012
Location: Kirk Michael, Isle of Man
Posts: 1,104
Default Re: What's this? A quiz.

I am not going to start googling, but i think the Wim-wam was a bit like perpetual motion and transmutation, a genuine belief of earlier times.
That was the impression I got from parental questioning. There really were less enlightened times (in a scientific sense, maybe not in other senses).
Les.
MotorBikeLes is offline   Reply With Quote
Old 18th Sep 2018, 8:43 pm   #28
ricard
Octode
 
ricard's Avatar
 
Join Date: Mar 2006
Location: Lund, Sweden
Posts: 1,248
Default Re: What's this? A quiz.

I've got a 16mm Eumig projector from the 1950's, which while currently fitted with a 250V lamp originally could be fitted with an 120V lamp, requiring an external voltage dropper of a similar type (I've never seen the dropper in real life, only pictures). The socket for the dropper is still there, but there's a short circuit plug for it (which must be unplugged if for whatever reason one wants to run the projector without the lamp turning on).
ricard is offline   Reply With Quote
Old 19th Sep 2018, 7:16 am   #29
raditechman
Heptode
 
raditechman's Avatar
 
Join Date: Feb 2007
Location: West London, UK.
Posts: 595
Default Re: What's this? A quiz.

The GBL516 16mm projector used a resistance box.
Article on link below includes picture of the resistance unit.
John
http://www.villagehallcinemas.co.uk/...m_9_gbl516.htm
raditechman is offline   Reply With Quote
Reply

Thread Tools



All times are GMT +1. The time now is 11:43 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 - 2018, vBulletin Solutions, Inc.
Copyright ©2002 - 2018, Paul Stenning.