Substitutions

Any reason for not substituting 1N4005 with say 1N4004 or 1N4007. Or 7805 for 78L05? I know that with 78L05 it is bigger, but is this it's only differance? Some of these parts are obsolete such as the H21L01.

A substitution list would be nice if there can be substitutions that is?

The 1N400X diodes are just different max reverse voltages. From memory 1N4001 is the lowest at 50V and is quite adequate for 12V system so any in the series will do.

I think you got the 78L05 the wrong way round. 7805 is bigger than 78L05. It will work but it won't fit the PCB.

Yes the H21L01 does seem to be obsolete, I can't even find a datasheet.

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[www.hydraraptor.blogspot.com]

Sorry Nophead, you are right I did get the 78L05 and 7805 reversed, I didn't notice the pin configuration before I asked. On the H21L01 Robot Objects sells an H21A2 could this be used to replace repraps suggested part?

Slotted Optical Switch, Fairchild H21A2 (SNSR-FCH21A2)



The Fairchild H21A2 Phototranistor Optical Interrupter Switch has become a standard for encoders and similar applications. It combines an infrared (IR) LED and compatible phototransistor in a single, IR opaque housing.

The gap in the housing provides a means of interrupting the signal from the IR LED to the phototransistor, switching the output from "on" to "off." And the two holes in the sensor housing make it very easy to mount the sensor on your robot.

INPUT (IR Emitter)
continuous forward current (IF): 50mA
reverse voltage (VR): 6V
OUTPUT (Phototransistor Sensor)
collector to emitter voltage (VCEO): 30V
emitter to collector voltage (VECO): 4.5V
collector current (IC): 20mA

Perhaps these will help with your optoswich question, I just ordered 6 of them.


Ron

[nl.farnell.com]

Edited 1 time(s). Last edit at 07/29/2007 05:31PM by Ron Luttik.

> Yes the H21L01 does seem to be obsolete, I can't even find a datasheet.

I believe that the last two characters in its name are the letters O and I (oh and eye), not 0 and 1 (zero and one). Its information page is at [www.fairchildsemi.com] and states that it is in full production. This may help you find both the part and information about it.

Its datasheet is at [www.fairchildsemi.com]. It is in stock at both DigiKey and Mouser, as far as I can tell. Mouser part number is 512-H21LOI, and Digikey part nuymber is H21LOI-ND .

Jonathan

Thank you both Janathan and Ron, I was just about ready to buy the emitter and collector and build my own housing to fit.