Topic: About the Solar Sensor

[wxtech]

You may know that I was a technician before retiring.  If it has screws, that's an invitation to open for exploration.  If it doesn't have screws, then I must saw it open.  Anyway, I had a cruddy Solar and UV sensor pair that needed cleaning.  I thought longer cables would allow me to terminate all the Davis sensors in a J-box.
So now, I have an enclosure with easy connections to Solar, UV, rain gauge, anemometer, 2 solar power panels, and the aspirator fan motor.
The project begins.

[wxtech]

Opening the solar sensor enclosure, I find the circuit board.  I draw a schematic from the board pattern.

[wxtech]

I provided a schematic of the solar sensor on other topics.  I don't know where that schematic came from.  This is the first time I've seen the circuit pattern and now I've drawn my version of the circuit.  Attached is a diagram that I believe is correct.

[wxtech]

The UV sensor has similar connections.  Yellow is +3volts power pulse, red & black are common, green is a voltage level output to the SIM during the time that the power is applied.  I did not open and diagram the UV circuit.  The UV circuit board picture is attached.
If anyone has a UV sensor that has failed, send it and I'll open it and diagram the circuit.  I'll repair it if possible, no guarantee.

[linuxfreak]

Hey Al,

Could you post the part number off of the UV sensor, the metal can sensor chip that is???  Can't see it too well in the photo.

George

p.s. - While snooping around about the PIN diode for the solar sensor I found the following 2 items.

[wxtech]

Hey Al,
Could you post the part number off of the UV sensor, the metal can sensor chip that is???  Can't see it too well in the photo.
George
p.s. - While snooping around about the PIN diode for the solar sensor I found the following 2 items.

The sensor part number would be good to know.  But I didn't read or write the component P/N.  I'll go back in and do some more snooping. 
The top of the UV sensor enclosure is white plastic.  But visible light enters only through the small (1/8") bump.  What I saw was purple-blue light coming in only through that small spot to the light sensor diode.  The shape of the plastic forms a lens to filter light from above and a portion from a lower angle.
What other information should I gather in the next exploration of the UV sensor?  I'll consider making a schematic if I can easily remove the metal shields from the circuit board.
The UV circuit board uses surface mount components for a more crowded device.  It'll be more difficult or impossible to diagram it.  I'll send pictures.

[wxtech]

Hey Al,
Could you post the part number off of the UV sensor, the metal can sensor chip that is???  Can't see it too well in the photo.
George

The numbers on the can are 3446, then a space and 5C.  It is in a TO5 window can just like the solar sensor.  It has 3 leads.  The center lead is connected to the can.
It is labeled D1 on the circuit board.
Al

[DaleReid]

Al,
Curiosity got the best of you, I see.

You'll need to amend your statement about screws to include silicon seal.

[Skywatch]

Can you get a picture of the top of the solar sensors sensing component?

[wxtech]

Can you get a picture of the top of the solar sensors sensing component?

Top view of the VTB5041 sensor on the solar sensor circuit board.  That's a screwdriver blade that I'm using to hold the board for the picture.

[Skywatch]

Awesome!