Project 4 - Phototransistor

Hi All,

I've noticed a few details about my kit (no wooden base, only 1 red and 1 black long wire) that make me feel like the contents and components may have been switched up since the manual was printed. I wanted to confirm in my picture, is this a phototransistor?

It kind of looks like what is printed in figure 1,

but nothing like what is printed in the "getting to know your parts" section or on the page prior to figure 1.

I hooked it up in module 4 as if it was one. The LED definitely seemed to change colors as I placed my fingers over them to hide the light, but not as I would have expected once the gels were applied. I did read through the thread of the dude having trouble with the green gels. I couldn't get any where near expected results.

Also I didn't find anything in my kit matching the picture that acts as kind of a gel-mount for the alleged phototransistor. Are these not provided anymore?

Thanks!

A give-away for a CdS photo resistor is the zig-zag appearance of the front face.

Note that a photo transistor is a completely different device.

I wanted to confirm in my picture, is this a phototransistor?

Yes. I just built project 4 and was a bit confused too.

By the way the picture in the book is all wrong. It shows the phototransistor facing the other way, but the anode should be connected to the power.

lukasauren:
By the way the picture in the book is all wrong. It shows the phototransistor facing the other way,

Does your version of the book have the same photo as the one Bendezium posted? That shows photoresistors, not phototransistors. Or do you have the newer version of the book with the phototransistors?

Which photo are you talking about? The one with the components on the breadboard or the schematic?

What do you mean by "anode"? Transistors don't have anodes, they have a base, collector, and emitter. In the case of the phototransistor you only have collector and emitter pins.

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