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[There is an english translation in the comments section. It was done by PedroDaGr8, to whom I am grateful]
Los otoscopios a lámpara suelen poseer dos características poco eficientes: el alto costo de reemplazo de su lámpara y el gran consumo que estas lámparas poseen, agotando rápidamente sus pilas o baterías.
Este instructivo muestra cómo convertir un otoscopio Heine para que funcione con un led sin tener que soldar, el cual tiene un muy bajo costo de reemplazo, muy bajo consumo y puede incluso mejorar el nivel de iluminación.
Si bien el método es generalizable a prácticamente cualquier marca y modelo de otoscopios, otros poseen interiores diferentes que puede requerir algunos cambios en estos pasos. En otro instructivo se abordará alguno de ellos.
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Signing UpStep 1Elementos
- Otoscopio Heine.
- 3 leds (si todo sale bien utilizarán sólo uno, pero puede que lo conecten al revés y se queme, o que las patas se rompan, o que queden cortas, por lo cual es mejor comprar de más aprovechando lo baratos que son). Deben tener las siguientes características:
- Blancos
- 5mm
- Luz fría (es la luz que no es amarillenta, pero atención: hay leds de luz fría que tienen un tono azulado. Esos tampoco son adecuados. Pruébenlos antes de compralos).
- 20 grados de ángulo de apertura (la más común). Debido a que la luz es dirigida internamente por fibras ópticas, otros ángulos no parecen influir.
- La mayor cantidad posible de milicandelas (mcd) -intensidad luminosa-. Aquí utilicé uno de 18.000 mcd, pero uno de muchas menos (por ejemplo, 4.000) puede que ilumine muy bien debido a la concentración que producen las fibras. Hay que probarlo. La diferencia de precio entre los de menos mcd y los de más mcd es muy poca.
- Alicate o tijera grande.
- Pinza.
(Podría necesitarse soldador y estaño en caso de surgir ciertos inconvenientes según el modelo del otoscopio y del led que se consiga -ver Paso 5-).
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First Page: Otoscopes have two major drawbacks: the high cost of replacing the bulbs/lamps and their rather limited battery life.
This instructable shows how to convert a Heine otoscope to LED without soldering. Which results in a much lower replacement cost and even increased illumination over the standard bulb/lamp.
While this method is more or less generic to any otoscope, some may have different designs/layouts which may necessitate changes to some of these steps. I will address some of these in another instructable.
Step 1: Elements
- Heine Otoscope
- 3 LEDs (only need one but it is better to have a few spare in case problems arise) The LEDs should have the following characteristics: *White
*5mm
*Neutral White (the author states cold white but without blue tint and not
warm white which has yellow tint, usually this is called neutral white).
*20 degree angle emission (because the light is collimated by fiber
optics other angles do not seem to have an issue, this is just the most
common) [a bit confused with the last part here but I think that is what
he is saying]
*Get the brightest LED you can, these are 18000mcd, though a weaker
one such as 4000mcd may still work fine due to the collumating effect
of the fiber optics.
-Wire cutters (the author calls them scissor pliers but a later image
shows wire cutters)
-Pliers
(Soldering iron and solder may be necessary if problems arise, if this happens come back later). [I assume for the aforementioned instructable]
- Degrees: it's perfectly interpreted (other degrees seem to make no difference).
- Wire cutters: that's the correct translation of "alicate" but the second part "o tijera grande" means "or a big scissor", because the leg of a led can be cut easily.
- Soldering iron: I was not clear enough. Now I have change it, directing the reader to the Step 5 in that case)
Thanks for your interest.
I consider the instructable translated and will include a note to these translation entries.
Thanks again
Because of this, I've tested its color quality with the users themselves: they say that a bright white led has similar color properties that the original lamp.
Step 5: Closing the otoscope
Turn the power switch on.
Close the otoscope slowly, making sure that the negative lead of the LED will touch the threads of the lower metal part or the metal at the top, where the LED is inserted. If the LED is lit before the otoscope is fully closed, the positive lead of the LED may be too long, but in the end you know everything works right so far. Just turn the otoscope off, open it and trim the positive leg a bit. Repeating until the otoscope works properly.
Depending on how the otoscope is threaded, the negative lead of the LED may prevent the device from closing properly. An alternative (though the original option is the preferred method) is to try to have the negative lead touch the metal of the upper section by bending the lead a bit backward. If it still does not turn on, because it doesn't make good contact with the metal, you will need to solder the negative lead in place. There are a number of instructables on how to solder LEDs, which should be done with some care so that you do not burn the LED. DO NOT SOLDER THE POSITIVE LEAD TO THE BATTERIES.
Authors edit: Added a photo of the soldered version with an LED that could not be fully inserted.
Step 4: Installing the LED
Insert the LED in the top where the bulb/lamp was previously.
Unfortunately, despite having the same spec'd diamter (5mm) tiny differences between LEDs cause some to not fit completely in the whole, while others will fit just fine. In my case, some that I acquired at a local business fit just fine while others stuck out a bit.
Although some stuck out a bit, it did not appear to affect the intensity of the light emitted from the otoscope. When the LED does not insert completely, you may have to cut the short leg (negative/cathode) less than directed and the long leg (postive/anode) more than directed. This is because the negative leg will now be deeper inside the metal otoscope (where it should touch the metal), while the positive leg will be closer to the lower section (where the batteries are with which the positive leg must touch). This is to prevent the leads from breaking or losing contact when closing/reassembling the otoscope.
Step 3: Prepare the LED
The LED has a short leg (corresponding the cathode/negative leg) and a longer leg (corresponding to the anode/positive leg).
1) Bend the short leg 90° in the forward direction (as shown in the picture). [I combined steps 1 and 2 for clarity]
2) Cut the leg with wire cutters to around 5mm*
3) Cut the other one at 3mm*, leaving it straight.
*Due to the differences between otoscopes, it is prefferable to cut the leads a little longer than necessary (for example 7mm and 5mm) and the trim the leads back to the proper lengths later on in the process.
Step 2: Open the Otoscope
Unscrew the top section.
Remove the lamp (it may be necessary to use pliers)