Cheap Sensors@Goldmine
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Just received an order of various sensors from Electronic Goldmine and after some bench testing, two sweethearts rose to the top.
Phototransistor: http://www.goldmine-elec-products.com/prodinfo.asp?number=G17837 has a particularly nice response to a candle flame. Might be of interest to anyone doing the Trinity Firefighting contest. $1.29, I'll buy more.
Photoreflective sensor: http://www.goldmine-elec-products.com/prodinfo.asp?number=G18740 is TINY and has a nice response to white/black lines on paper using only room light for illumination. Didn't even fire up the onboard LED, rated for up to 60 mA! With the proper resistors, could work nicely for line sensing or wheel encoders. $1.00, you can't make one this cheap.
I was less impressed with these photocells: http://www.goldmine-elec-products.com/prodinfo.asp?number=G15177 I ordered 4. Two of them were fairly matched but the other two were quite dissimilar. Shouldn't we have photocell manufacturing down pat after 75 years?
Phototransistor: http://www.goldmine-elec-products.com/prodinfo.asp?number=G17837 has a particularly nice response to a candle flame. Might be of interest to anyone doing the Trinity Firefighting contest. $1.29, I'll buy more.
Photoreflective sensor: http://www.goldmine-elec-products.com/prodinfo.asp?number=G18740 is TINY and has a nice response to white/black lines on paper using only room light for illumination. Didn't even fire up the onboard LED, rated for up to 60 mA! With the proper resistors, could work nicely for line sensing or wheel encoders. $1.00, you can't make one this cheap.
I was less impressed with these photocells: http://www.goldmine-elec-products.com/prodinfo.asp?number=G15177 I ordered 4. Two of them were fairly matched but the other two were quite dissimilar. Shouldn't we have photocell manufacturing down pat after 75 years?
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Comments
http://www.goldmine-elec-products.com/prodinfo.asp?number=g17290
Hand Held Magnifier
http://www.goldmine-elec-products.com/prodinfo.asp?number=G17336
Tweezer Assortment
http://www.goldmine-elec-products.com/prodinfo.asp?number=G17664
Stop buying up all the stock! Let some others get in on the bargains, whydontcha?
Those CdS cells you pointed to: they're different even in the photo (one is much thicker than the other). Not surprising you got dissimilar results.
The retro-reflective sensors look cool. It's also nice to see these are the same kind Rodan uses in his fights with Godzilla. They gotta be good.
-- Gordon
The more I think about them, the more uses I come up with. Touch sensors, proximity sensors, general object sensors, Hot Wheels car sensors. They're plenty sensitive. Even though they're just a phototransistor (as opposed to the wonderful but sadly discontinued Hamamatsu P5587 sensor, which had internal amplifiers & schmitt trigger output) they can be made to work just fine with some hardware & software tweaks.
Heck, for a buck each, I'll buy 'em all up and scalp 'em to my beloved forum pals.
"psst, wanna buy some sensors??"
{now, trying to get picture out of my mind}