Q1 fell off

simplesimson

Hi,
my Diode Q1 fell off. Maybe something hit it a while ago. Or it just got ratteled off over the years. How do i know which way to solder it back on? polarity I think polarity is important .. And if its broken, what is the correct spare part?

Couldnt find the layout so I hope somebody can help me.

Regards
Simon

jay_s_uk

might help us if you tell us what board you are talking about.
also the revision if applicable

simplesimson

The board looks like this one from filafarm. Thats also where i got it about 2 years ago.
I just tryed to meassure the voltage drop and had to see that the endcaps still are in the soldering on the board. Meaning only the middlepart of the diode break lose.
So i need a replacement diode.

jay_s_uk

The schematics can be found here https://github.com/dc42/OrmerodSensorBoard

dc42

The polarity does matter. There is a green square on the back of that part, offset from the centre. It should be oriented on the side towards the black capacitor, away from the board edge.

simplesimson

Thanks a lot for your help guys. I ordered it and am looking forward to repair it.

simplesimson

source: https://github.com/dc42/OrmerodSensorBoard/blob/master/SchematicAndPCB/Mini-differential-IR/V1.2/board.png
@dc42 the parts arrived. but i think i have to point the green square on the back as shown on the scematic or? so that its towards the corner of the pcb, away from the black capacitor, or?

Regards, Simon

EDIT: I tryed it as you described. I had to face green square to the outside for it to read