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If you're silly enough to try this, then at your own risk be it!
Left-Right Reversing Television
This cunning piece of meddling with the electrickery inside a television set gives the ability to see the pictures of the screen reversed, as in a mirror. Right is left and left is right, hovering in the fog of the wicked night.*
In the entry-level version, it's just fixed with the picture reversed. In the de-luxe version, a switch is added so it's possible to switch between normal mode and reversed mode.
The electronics of this are a bit like the business of how to make a television into an oscilloscope, but the psychological ramifications are much more interesting than the electronics. Some of this page is the same as that page, as the method is similar.
Now before going into details about the method of construction, a safety warning. Televisions are dangerous if you open them up, and opening up a television set without making the correct precautions first can be hazardous. So, before opening up the television you should check that you own it or have the permission from whoever owns it, or it could be risky as the owner of the television might get cross about it! Electricity is also dangerous, so you should be sensible about that too.
Now, here's what to do:
1. Locate the deflector coil assembly. This is a big coily thing which is all around the neck of the television tube. Or to put it another way, the tube neck is right in the middle of the television, and the deflector coil assembly is around it and further forward.
2. Locate the wires going to the deflector coil assembly. Ideally there should be four of them. Two of these are the horizontal and two of them are the vertical. It is the two which are the horizontal which are of interest here.
3. Find out which are which. (Worth taking time to get right rather than guessing, as an unlucky guess can blow the frame output!). To find out which are which, you need to snip the wires one at a time and reconnect them one at a time in turn and see what happens. If either of the horizontal are disconnected, then there's no horizontal, so you see a vertical line. Special care should be taken not to electrocute yourself.
Having found which two wires are horizontal, you SWAP THEM! This reverses the picture left-right. Very curious.
Now the de-luxe version:
1. Get a double-changeover switch. This is of the type with six connectors. Two of these are "common", two of them are "position 1" and the other two are "position 2".
2. Connect the two wires from the deflector coil assembly to the two "common" on the switch.
3. Connect the other two wires to the two "position 1" terminals.
4. Connect an extra pair of wires from the "position 1" terminals to the "position 2" terminals but swapped over.
5. Test the whole arrangement in both positions and make sure it all works.
So, there it is, the ability to have left-right reversed television. If you watch telly with a mirror - image picture it looks mostly the same, and if someone coming into the room not knowing this will probably not notice to start with. Unfamiliar landscapes and people look the same with the picture left-right reversed. Then you start to spot the exceptions...
# They're driving on the wrong side of the road. Easily mistaken for being in a different country.
# Text is reversed. This is the obvious difference, but text on screen is sufficiently rare that it's possible to maintain the illusion for some time!
# Geography looks VERY STRANGE. Weather reports showing reversed geography with alien land-formations, etc.
# That which is familiar becomes unfamiliar. Scenery which you have become accustomed to being that way round sometimes looks near unrecognisable the other way around.
# Various other symmetry conventions are reversed. These suddenly become noticed because the assumptions are at odds with the observations, and the differences then show up as if magnified. For example, clocks, the preference for putting a stamp on the top-right of an envelope, which side coats fasten, left-handedness with knife and fork, etc.
Another similar trick that can be done to a telly is the oscilloscope conversion
Extra note: I have been asked if the same electrical principle can be applied to the vertical coils to make the television picture turn upside-down, for example for the purposes of projector tv systems. See http://groups.msn.com/DiyProjectionTV (gone) ... YES! It can. In fact both horizontal and/or vertical can be reversed in the same tv. And, in the double de-luxe version, TWO reversing switches are installed, one for horizontal and one for vertical!
Special safety note: On some televisions, there are dangerously high voltages even a while after the set has been switched off. Make sure you find out if the set you are working on is of that type by using a neon screwdriver, rather than the hard way!
Sinister note: A special mention about a hidden danger of left-right reversing. Try to avoid dwelling on looking at your own face. The reason for the danger is not in any actual asymmetry, but in the cruel illusion which the brain creates. If you are having trouble because of a perception of facial asymmetry, I can tell you why it creates this illusion, how it works, and what can be done about it. Don't panic! Write in. e-mail
* Variant on a line from the Scottish Play by Shakespeare, giving a poetic hint that there's something a bit "sinister" about the whole affair.
I used your web page to convert a security monitor and camera to a rear view mirror system for my streetrod, a '46 Mercury. It worked perfectly. Thanks for the info. The retail versions of the rear view systems are 259 US dollars and up. I used a 79 US dollar system.
South Mills N.C. USA
I just thought that I'd let you know that a reversing camera for my motorhome in the UK would set me back about £180, on the other hand a small 12v black and white domestic system is about £40. The problem obviously is that it isn't a mirror image which makes it very difficult when reversing. Using the left - right reversing as described on your website it works a treat and has saved me £140 thanks very much, reversing is so much easier and because on the domestic system I have two way audio which you don't have on the "proper" model, if anyone is at the back of the motorhome, I can actually talk to them through the system advising them to MOVE. I would never have thought of doing this as I have no electrical knowledge whatsoever had it not been for your website, thanks again.
It would be nice to find a way to perform these tricks with a flat-screen, but so far we only know how to do this because of the way the CRT works.