PIC based weather monitor for Astro
Updated April 30, 2010, driver updated to report PWS (Personal Weather Station) info to Wunderground
Update April 14/15, 2010 PCB's Arrived!
Update April 13, 2010, 7 day connected graphs and page cleanup
Update Arpil 7, 2010, out for PCB! images below
Update Mar 31, 2010
Update Oct 7, 2009
Page created June 26, 2009
My other projects:
Replacment clone of the Meade 909APM
USB to ST4 adapter
Enable "PWS and Airports" and "Rapid Fire Updates" and select "Greenbox Observatory"
Note: Unit may be on or offline at any time and possibly offline for extended periods of time as development of software continues
PCB's arrived April 14, 2010
So far I have tested the short range BT module and the main PCB for cloud temp, gentle heater, ambient temp.
All looks good so far! The unit is running outside now to check capability of 'gentle heater' to keep dew off.
I hope tonight like last night, I had to scrape ice on the car windows!
The gentle heater is the 'camping configuration' where you set it in the field and it only provides cloud, light, ambient readings
and a buzzer to wake you if clouds roll in or clouds roll out.
Sensors are: Thermopile left in the white cap, ambient light, ambient temp, humidity.
Board left is main board, board right is short range bluetooth module
First 'light' night, clouds rolled through for a while
Input/output of the GC-Weather1 (click image for PDF of image)
PCB layout as ordered 4/7/2010 (1.9"x3")
Optional short range Bluttooth module 1"x1.75" as ordered 4/7/2010 (10M Class 2)
7 days of weather monitoring
Connected via bluetooth 7 days
Notice the blue line (sky brightness, higher is darker) versus white line(measured sky temp, lowere is clearer)
My light pollution is so bad even the cds photocell light detector can see the clouds :-(
End of update for 3/31/2010
Current unit. Pegs out top are for bird determent, bluetooth inside downtube
12V power input
Update July 16, 2009, results of the bluetooth connection.
So far the unit works well. It has been up and running since my last post (7+ days). I had one connection running 4+ days (until wife needed the netbook for a trip) and another connection since then. The flexibility of feeding it 5V power on pin 9 of the DB9 lends itself to no extra power cables which other seem to require. This was all in a coexistent environment with wireless networking and microwave ovens. Both PC side machines only connect wireless to the net and both are within 15 feet of a microwave oven. When the microwave is on the laptop closest to the oven it looses connection to the net but the bluetooth unit seemed impervious to it, just kept on being connected.
Here is a screen shot before disconnecting the netbook:
Update July 9,10 2009
GUI display of unit running bluetooth connected
Distance to head about 140ft, PC inside house and through a double layer sliding glass door.
RS232 to bluetooth adapter used
PC side adapter used
Time interval: 07/08/2009 08:06 PM -> 07/09/2009 05:40 AM EDT, samples every 4 minutes
A semi clear night (hazy skies), notice the left display blue dome shaped line.
This is the ambient light detector showing darkness.
July 10 with random clouds moving through and some wind at beginning of the night
Notice the domed shaped blue line, the ambient light detector. My light pollution is so bad the
ambient light detector picks up the added sky brightness from clouds anyplace in the sky.
Compare the range shown for ambient with the screen shot from July 9 below
July 9 a mild night
From July 3, 2009
Still to do - attach bluetooth to rs232 serial adapter (on order)
Add the SSR relay chip inside (TLS227A)
Test, test, test
Sensor plate (reason for needing the micro-mill :)
Recessed area for floating the rain sensor/heater in heatsink grease and clamped down
Using the built in heater only for the whole head the power requirements with heater on are <0.6A @12V
The thick film heater on the underside of sensor is 42ohms for ~0.3A @ 12V (3.4W)
Capable of heating sensor head to > 40C above ambient in 5MPH winds
Looking down on top of the mounted unit
Looking up at the unit mounted
Mounted outside of Greenbox (my observatory)
Old anemometer seen in background
PC GUI display
Image showing prototype board, provides for features of:
- Cloud detector via thermopile
- Rain sensor - capacitive type with integrated heater
- Ambient temperature (DS18S20)
- Humidity (HIH-4000-001)
- Wind detector - 'Hot transistor 2N4401' type
- Ambient light (daylight) detect
- Heater for sensor head
Yet to add to prototype:
- Add relay output
- Add rs232 interface
- Add wind cup anemometer support/selector
- Fabricate head to carry sensors
- Mount in case
- Test, test, and more test
- Try a few different bluetooth to serial adapters
Base proto board:
Provides selector for CDS photocell, Photo transistor/photodiode
Power requirements subject to change(bluetooth rs232 unknown as of now)
- Heaters off, hot transistor wind detector: 100ma-200ma @ 12V
- Heaters on, hot transistor wind detector: 1.4A-1.6A @ 12V
- Heaters off, moving cup anemometer: 50ma @ 12V
- Heaters on, moving cup anemometer: 1.35A @ 12V