Twin Headlamps

Hi All,
Twin headlamps were something to aspire to back in the 70s.
We’re they mostly a pair of main beam and a pair of dipped?
Or were they main/dip in each unit?

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

On my Mk III Cortina it was a pair of main beam & a pair of dipped
--
from KT24 in Surrey, England
"I'd rather die of exhaustion than die of boredom" Thomas Carlyle
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Ditto on my Alfa Sud. Outers were dipped beam and inners main.
Tim
--
Please don't feed the trolls

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

If Lucas, most common was a twin filament dip, and a single filament main beam. So one pair only on dip, both pairs (with a higher beam from the dip units) on main.
--
*Acupuncture is a jab well done*

Dave Plowman snipped-for-privacy@davenoise.co.uk London SW
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
snipped-for-privacy@o2.co.uk used his keyboard to write :

Sealed beam units, one pair had dip, one main. Another car had one pair of combined with a separate pair of mains. Dips were always switched off when mains were on.
My present car is a four headlight xenon job, but the dips remain on with mains.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
message used his keyboard to write :

I think when I saw twin-headlight cars in the 70s with their main beams on, all four headlights were lit, so I presume one pair of lights had twin filament dip/main and the other pair had just main. I don't remember seeing cars where one pair of lights went out when the other came on.

I think most of the cars that I've owned in the last 20 years have kept the dipped filament on when the beam is on.
What was the main reason that cars changed from sealed beam to replaceable bulb in fixed reflector? My mum's Renault 6s and my dad's later Citroen GS in the 1970s used bulbs, but his Hillman Hunters and his Ford Sierra used sealed beam. Maybe bulbs started out as a French (or other European) thing, and British cars carried on for longer with sealed beam.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
NY wrote:

You mean that twin filament bulbs are using both simultaneously?

I think the cost of replacement was too high. Also it was a design constraint, you were stuck with a standard shape.
Chris
--
Chris J Dixon Nottingham UK
snipped-for-privacy@cdixon.me.uk @ChrisJDixon1
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Chris J Dixon pretended :

No, not in a combined unit - always one on or the other.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
I well remember my first P6 Rover - a Mk1 3500. Standard Lucas 5 3/4 sealed beams. Dips were 37 watt and pathetic. Far worse than a standard Lucas 7" sealed beam.
Changed them to Cibie halogen units which at 55 watt were a big improvment. Had to re-wire, so the dips stayed on with main beam.
Later, twin filament halogen bulbs became available. And with those you could run both filaments at the same time. Arranged them so main beam had all 8 filaments running. Half a kilowatt of light. ;-)
Had a switch so dips were either two or four filaments.
--
*When the going gets tough, the tough take a coffee break *

Dave Plowman snipped-for-privacy@davenoise.co.uk London SW
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Wed, 20 May 2020 10:56:13 +0100, Dave Plowman (News) wrote:

Hopefully all switched through an appropriately rated relay and fuse ?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Twin relays, actually. Fed from the main battery cable via fuses. Even a small amount of voltage drop makes a big difference to the light output.
--
*No hand signals. Driver on Viagra*

Dave Plowman snipped-for-privacy@davenoise.co.uk London SW
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Wed, 20 May 2020 13:03:57 +0100, Dave Plowman (News) wrote:

When the (not road legal :)) 90/100W halogen conversion bulbs became available I rigged up a relay system for my car to fit them.
I also rigged up a relay to disengage the fog light when the ignition was off, since it seemed beyond the wit of manufacturers :)
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Ignition switch already near its limit?
--
*Friends help you move. Real friends help you move bodies.

Dave Plowman snipped-for-privacy@davenoise.co.uk London SW
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Wed, 20 May 2020 16:46:47 +0100, Dave Plowman (News) wrote:

Dunno ? But I rigged up a relay that once energised fed it's own primary so the foglight stayed on as long as the ignition was on. Ignition off, foglight off, and needed to be switched on again. Made it impossible to accidentally leave it on. (I frigged the foglight switch to remove the lock, so it was just push-to-make ...)
That was 25 years ago ...
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

Thinking of modifying the behaviour of switches, my dad modified the cigarette lighter (none of us smoke) so it make a simple latching switch. And he wired it in series with the ignition switch as a crude anti-theft device. This was in the 1970s. I imagine today's car thieves would find a way round that :-( I remember he got my grandpa to turn a steel disc which had the same profile as the cigarette lighter element so the contacts would still hold it in the "in" position. He had to remember to reverse the changes when he sold the car!
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Yes. My latest car has H7 twin filament bulb and H7 single filament, in separate housings within the headlamp/sidelight/driving light/indicator cluster. I'm sure the dipped filament remains alight when the high beam is on.
Yes, just checked. There is a difference between headlights on at light switch (when main beam is both dipped and main filament) and headlamps being flashed with light switch off (which is only main beam filament).
But older cars with sealed beams or H4 bulbs seemed to turn the dipped filament off when the main beam was turned on - which meant that *both* filaments (dip and beam) were constantly being switched on and off as each oncoming car approached (dip the headlights) and went past (back to default state of high beam). I wonder if keeping the dipped filament on all the time was done partly to reduce the thermal shock of it being turned on and off all the time, as well as the more obvious advantage of providing a bit more light.

I always wondered why sealed beam lights became so common, given the much higher replacement cost and the much larger object to carry around as a spare. I suppose there was one less variable in getting the headlamp alignment correct, in that filament was always in exactly the same place in relation to the reflector, rather than there being a bit of variation if the bulb wasn't perfectly seated in the reflector housing. I always wonder whether I should get my alignment checked after changing a bulb, because of seating variations between bulb and reflector.
Embarrassing admission. After having my car 12 years, I discovered that it has an extra set of lights for daylight running lights, which were turned off at a menu on the dashboard. These are dimmer-than-dipped filament bulbs in a separate housing, rather than LED: my car is probably just too old for LED technology to be bright enough, so they used filament.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
NY laid this down on his screen :

I think happened, when halogen lamps came along.
It began with ordinary bulbs, then along came sealed beams - which improved massively on separate bulbs, then halogen bulbs (brighter, whiter) demanded separate reflectors and lens again. They couldn't make halogen work in a sealed beam unit.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

To allow halogen bulbs. Although these days you could have a truly sealed beam with a halogen capsule.
--
*IF A TURTLE DOESN'T HAVE A SHELL, IS HE HOMELESS OR NAKED?

Dave Plowman snipped-for-privacy@davenoise.co.uk London SW
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Wed, 20 May 2020 08:17:52 +0100, Harry Bloomfield, Esq. wrote:

Not all cars with twin headlamps were sealed beam.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Jim GM4DHJ ... explained on 20/05/2020 :

The twin headlights, or the aspiring?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.