Cybercow
Well-known member
Found these in an estate sale box I got a while back. My Peak Atlas DCA75 says they are Darlinton BJTs with an hFE of about 32,000. For two reason s I suspect they are some type of opto-device:
1) they have transparent bodies and
2) when I put them in direct sunlight, they read as dual Zener dioes, but if I cover them with a bit of black heatshrink, they read as shown in the first photo.
(I removed the heatshrink after obtaining the reading.)
When I test them in a darkened room and a lit LED in proximity of the device's face, they continue to read as Darlingon BJTs, but with higher and varying hFE values - depending on the brightness of the lit LED.
Any idea what the part/device number might be? No printing on them all. Never seen such a device before.
I know they are some sort of phototransistor, I'd just like to identify the part number.
1) they have transparent bodies and
2) when I put them in direct sunlight, they read as dual Zener dioes, but if I cover them with a bit of black heatshrink, they read as shown in the first photo.
(I removed the heatshrink after obtaining the reading.)
When I test them in a darkened room and a lit LED in proximity of the device's face, they continue to read as Darlingon BJTs, but with higher and varying hFE values - depending on the brightness of the lit LED.
Any idea what the part/device number might be? No printing on them all. Never seen such a device before.
I know they are some sort of phototransistor, I'd just like to identify the part number.
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