<![CDATA[WeatherDuino Forum - User support forum for 4Pro Weather Station Transmitters]]> https://www.meteocercal.info/forum/ Thu, 30 Apr 2026 10:05:46 +0000 MyBB <![CDATA[4Pro TX Parts]]> https://www.meteocercal.info/forum/thread-2357.html Mon, 03 Mar 2025 20:19:13 +0000 HeavyWeather]]> https://www.meteocercal.info/forum/thread-2357.html WeatherDuino 4Pro TX Board Parts

Hello everybody!

I have done a little work to help those struggling to find parts to complete your transmitter boards. I have created a list on DigiKey for everyone to access, but for the moment it is only a parts list for the specified countries/setups. If you would like a parts list for 433 MHz, a different country, or specific specifications of your TX board, PM me and I will absolutely be willing to create more lists for you!

Be warned though. I made this list a week ago and had to use some substitutes for obsolete and out-of-stock parts, but they should still work the same. You can also PM me for any questions, issues, or tips on ways I can improve the lists for you all.

These lists are not just lists but links to DigiKey where you can order the exact amount of parts you will need for a board. The list contains parts that you may or may not need, depending on your choice of setup, so feel free to ask me about it.

I will edit this post and update this thread as I add, edit, or update the lists.

US & AU 915 MHz LoRa Parts Link:

Updated March 3, 2025.
https://www.digikey.com/en/mylists/list/MDHR29ENAA

EU 868 MHz LoRa Parts Link:

Note:
This part list does NOT include the 868 MHz LoRa module, as it is out of stock and special order through DigiKey. Eventually, I can post a second link to the LoRa module separately.

Updated March 4, 2025.
https://www.digikey.com/en/mylists/list/Z5OPUTSMVV


US & AU 315 MHz OOK Parts Link:

WIP

EU 433 MHz OOK Parts List:

WIP]]> WeatherDuino 4Pro TX Board Parts

Hello everybody!

I have done a little work to help those struggling to find parts to complete your transmitter boards. I have created a list on DigiKey for everyone to access, but for the moment it is only a parts list for the specified countries/setups. If you would like a parts list for 433 MHz, a different country, or specific specifications of your TX board, PM me and I will absolutely be willing to create more lists for you!

Be warned though. I made this list a week ago and had to use some substitutes for obsolete and out-of-stock parts, but they should still work the same. You can also PM me for any questions, issues, or tips on ways I can improve the lists for you all.

These lists are not just lists but links to DigiKey where you can order the exact amount of parts you will need for a board. The list contains parts that you may or may not need, depending on your choice of setup, so feel free to ask me about it.

I will edit this post and update this thread as I add, edit, or update the lists.

US & AU 915 MHz LoRa Parts Link:

Updated March 3, 2025.
https://www.digikey.com/en/mylists/list/MDHR29ENAA

EU 868 MHz LoRa Parts Link:

Note:
This part list does NOT include the 868 MHz LoRa module, as it is out of stock and special order through DigiKey. Eventually, I can post a second link to the LoRa module separately.

Updated March 4, 2025.
https://www.digikey.com/en/mylists/list/Z5OPUTSMVV


US & AU 315 MHz OOK Parts Link:

WIP

EU 433 MHz OOK Parts List:

WIP]]> <![CDATA[I2C problems]]> https://www.meteocercal.info/forum/thread-2350.html Sat, 21 Sep 2024 22:46:16 +0000 devonsun]]> https://www.meteocercal.info/forum/thread-2350.html
However there seems to be a problem with the I2C bus. On startup, the transmit LED only flashes 5 times then hangs. Looking at the serial monitor it fails to read or send the temperature/humidity data (SHT31). If I disable the T0 and T1 options in config options the system continues sending all the other data, and the test i2c detect sketch does not find any devices. If I fit the same arduino nano to an old Pro 2 Tx board with the same SHT31 it works perfectly, even with just the USB input as power.
On the 4Pro board the SCLOCK bus is high at 5v but the SDAT is only around 3 volts. Looking at the schematic, I would expect SDAT to be normally high 5V. I've checked the 4K7 pullup R6 and it is correct. Could the problem be one or more faulty I2C bus extender chips (IC3/4)perhaps? It's obviously not a dead short. Any other ideas before I start trying to isolate the SDA input pins on the bus extenders? Thank you.
Devon Sun]]>
However there seems to be a problem with the I2C bus. On startup, the transmit LED only flashes 5 times then hangs. Looking at the serial monitor it fails to read or send the temperature/humidity data (SHT31). If I disable the T0 and T1 options in config options the system continues sending all the other data, and the test i2c detect sketch does not find any devices. If I fit the same arduino nano to an old Pro 2 Tx board with the same SHT31 it works perfectly, even with just the USB input as power.
On the 4Pro board the SCLOCK bus is high at 5v but the SDAT is only around 3 volts. Looking at the schematic, I would expect SDAT to be normally high 5V. I've checked the 4K7 pullup R6 and it is correct. Could the problem be one or more faulty I2C bus extender chips (IC3/4)perhaps? It's obviously not a dead short. Any other ideas before I start trying to isolate the SDA input pins on the bus extenders? Thank you.
Devon Sun]]> <![CDATA[Connections for transmitter unit]]> https://www.meteocercal.info/forum/thread-2268.html Fri, 27 Oct 2023 14:04:41 +0000 Sun_Dancer]]> https://www.meteocercal.info/forum/thread-2268.html
I have finally finished my 4Pro transmitter unit.
Can the UVM-30A and the solar cell for solar radiation measurement be connected to the 4Pro transmitter unit directly without the solar/UV interface?
It is not yet clear to me how the solar cell or the UVM-30A are connected. I am currently using the interface, but I would like to do without it.
The transmitter unit can be supplied with voltage via a solar module. If I connect this to the 12V interface and if so, what does the battery look like, is it also connected to the 12V interface and/or do I need a charging module for the battery ?
My last question concerns the TX LED and the fan LED. In the parts list, the FAN LED is specified as a "Blue" LED, the TX LED has no color assigned. Can I also use other colors for the LEDs? As far as I remember, some colored LEDs also have different voltages. Would I have to replace resistor R8 with a different value to change the voltage for the FAN LED?

I just had a question about the HTU21 temperature sensor. I wanted to try out a different T/H sensor instead of the SHT31 and the HTU21. I received this sensor:
Si7021 Humidity Sensor Temperature Sensor I2C SHT21 HTU21 GY-21 Sensor Module
Can someone tell me exactly what kind of sensor I have? I can't find any explanation about the sensor on the web. In the firmware for the transmitter unit I can set 1 for SHT21 or 2 for HTU21 for TH Sensor0 and then I get identical values displayed on the serial monitor.
Can anyone give me a hint about this?

Greetings.....]]>
I have finally finished my 4Pro transmitter unit.
Can the UVM-30A and the solar cell for solar radiation measurement be connected to the 4Pro transmitter unit directly without the solar/UV interface?
It is not yet clear to me how the solar cell or the UVM-30A are connected. I am currently using the interface, but I would like to do without it.
The transmitter unit can be supplied with voltage via a solar module. If I connect this to the 12V interface and if so, what does the battery look like, is it also connected to the 12V interface and/or do I need a charging module for the battery ?
My last question concerns the TX LED and the fan LED. In the parts list, the FAN LED is specified as a "Blue" LED, the TX LED has no color assigned. Can I also use other colors for the LEDs? As far as I remember, some colored LEDs also have different voltages. Would I have to replace resistor R8 with a different value to change the voltage for the FAN LED?

I just had a question about the HTU21 temperature sensor. I wanted to try out a different T/H sensor instead of the SHT31 and the HTU21. I received this sensor:
Si7021 Humidity Sensor Temperature Sensor I2C SHT21 HTU21 GY-21 Sensor Module
Can someone tell me exactly what kind of sensor I have? I can't find any explanation about the sensor on the web. In the firmware for the transmitter unit I can set 1 for SHT21 or 2 for HTU21 for TH Sensor0 and then I get identical values displayed on the serial monitor.
Can anyone give me a hint about this?

Greetings.....]]> <![CDATA[TX board TX LED always on]]> https://www.meteocercal.info/forum/thread-2264.html Sat, 09 Sep 2023 02:17:51 +0000 HeavyWeather]]> https://www.meteocercal.info/forum/thread-2264.html
I have finally built my station and all seems to be well on the receiving side, but my TX board seems to have the TX LED constantly on, and no data is being sent. Let me know what my next steps should be.

Thanks, Michael]]>
I have finally built my station and all seems to be well on the receiving side, but my TX board seems to have the TX LED constantly on, and no data is being sent. Let me know what my next steps should be.

Thanks, Michael]]> <![CDATA[SMA connector]]> https://www.meteocercal.info/forum/thread-2193.html Sun, 25 Sep 2022 07:23:05 +0000 gtbwise]]> https://www.meteocercal.info/forum/thread-2193.html i am used to seeing the 4 support legs and centre through the board

geoff]]> i am used to seeing the 4 support legs and centre through the board

geoff]]> <![CDATA[antenna choice]]> https://www.meteocercal.info/forum/thread-2192.html Fri, 23 Sep 2022 12:19:43 +0000 gtbwise]]> https://www.meteocercal.info/forum/thread-2192.html
i will be using LoRa 915mhz transmitter on my system

what type of antenna are people using and where did you buy from ?

geoff]]>
i will be using LoRa 915mhz transmitter on my system

what type of antenna are people using and where did you buy from ?

geoff]]> <![CDATA[parts price]]> https://www.meteocercal.info/forum/thread-2186.html Fri, 02 Sep 2022 05:23:37 +0000 gtbwise]]> https://www.meteocercal.info/forum/thread-2186.html newby here

contemplating buying weatherduino 4 sender and receiver boards
can anyone give me a rough price for the parts on a sender board ?

geoff]]> newby here

contemplating buying weatherduino 4 sender and receiver boards
can anyone give me a rough price for the parts on a sender board ?

geoff]]> <![CDATA[TX serial monitor output]]> https://www.meteocercal.info/forum/thread-2167.html Thu, 05 May 2022 06:34:10 +0000 Nigel]]> https://www.meteocercal.info/forum/thread-2167.html As stated in another thread I've finally connected up my TX with wind and rain sensors.  All complete guess work as to wiring to the sensors.  I have powered up the unit and I have a LED flashing every now and again.  Werk has correctly suggested I enable debugging print to serial monitor.  The question I have is should I be seeing plain English or something machine readable only on the serial monitor.  From Werk's comment "coherent" I'm thinking it should be in plain English.  In which case I have debugging to do as I have a series of interesting but meaningless characters printing out on the serial monitor.
Nigel]]> As stated in another thread I've finally connected up my TX with wind and rain sensors.  All complete guess work as to wiring to the sensors.  I have powered up the unit and I have a LED flashing every now and again.  Werk has correctly suggested I enable debugging print to serial monitor.  The question I have is should I be seeing plain English or something machine readable only on the serial monitor.  From Werk's comment "coherent" I'm thinking it should be in plain English.  In which case I have debugging to do as I have a series of interesting but meaningless characters printing out on the serial monitor.
Nigel]]> <![CDATA[4Pro Universal Transmitter - General Usage & Assembling Guide]]> https://www.meteocercal.info/forum/thread-2067.html Wed, 18 Aug 2021 23:11:37 +0000 werk_ag]]> https://www.meteocercal.info/forum/thread-2067.html General Usage & Assembling Guide


1 - Setting the embedded Solar Irradiance / UV Index interface

1.1 Measuring Solar Radiation
The Solar Radiation / UV interface can be used with commercially available silicon photodiode pyranometers, provided their output voltage does not exceed 1.1V, for example the Apogee SP-110 Pyranometer. Although much cheaper than a professional thermopile pyranometer, commercial silicon photodiode pyranometers are still expensive, probably costing far more than the rest of the weather station combined. For this reason the WeatherDuino project is primarily designed to use a simple solar sensor based on a design by Charles G. Wright which uses a silicon photovoltaic cell, see Measuring Solar Radiation

Instructions below apply when using a 2Volt - 120mA, mini solar panel (please don't ask for support to other types of mini solar panels).

R14* = 1 Ohm Metal Film, 1%
RV1 = Adjust to 2.7K

Using those values your solar irradiance sensor is able to give you readings up to 1500 W/m2, with considerable precision, however for better results further calibration, by slightly adjusting RV1, is recommended.
Under ideal conditions (a cloudless day, around noon in mid-summer) the solar irradiance measured by the WeatherDuino solar sensor should be similar to the theoretical maximum.
The theoretical maximum solar irradiance for any location at any day of the year can be found using the Apogee Clear Sky Calculator.

If you intend to use the Apogee SP-110 Pyranometer as solar irradiance sensor, then R14* must not be installed.

1.2 Measuring UV Index
Instructions below apply when using the UVM-30A UV sensor.

RV2 = Adjust to maximum value (10K Ohm)
RV3 = Adjust to minimum value (0 - 100 Ohm)

If you intend to use the VEML6075 as UV sensor, then RV2 and RV3 don't need to be installed.


2 - The JP1 jumper
The JP1 jumper must be installed only when using a FineOfset wind vane.

Example of a FineOfset wind vane, sold under several brands.
.jpg FineOffset_WindVane_250px.jpg Size: 31,07 KB  Downloads: 495


With any other type of supported analog wind vanes (like Davis 6410 or 7911), JP1 should not be installed.
For a complete list of Weather Instruments supported by WeatherDuino, please refer to this page: https://wiki.weatherduino.com/supported_...nstruments


3 - LoRa or OOK radio
The transmitter can operate with LoRa or OOK radios. Depending on which mode you will intend to operate your transmitter, there are some components that you may decide not install.

3.1 Operating in LoRa mode
OOK radio, VR2 (78L09F), C4 and C5 don't need to be installed

3.2 Operating in OOK mode
LoRa radio, IC1 and C2 don't need to be installed.

3.3 Radio Select Shunt
Depending on operating mode (LoRa or OOK) there is an small shunt (RCS) that should be done using a drop of solder.
  • For LoRa, put a drop of solder between the right and centre pads.
  • For OOK, put a drop of solder between the left and centre pads.

.jpg RF_Jumper_500px.JPG Size: 52,79 KB  Downloads: 485
]]> General Usage & Assembling Guide


1 - Setting the embedded Solar Irradiance / UV Index interface

1.1 Measuring Solar Radiation
The Solar Radiation / UV interface can be used with commercially available silicon photodiode pyranometers, provided their output voltage does not exceed 1.1V, for example the Apogee SP-110 Pyranometer. Although much cheaper than a professional thermopile pyranometer, commercial silicon photodiode pyranometers are still expensive, probably costing far more than the rest of the weather station combined. For this reason the WeatherDuino project is primarily designed to use a simple solar sensor based on a design by Charles G. Wright which uses a silicon photovoltaic cell, see Measuring Solar Radiation

Instructions below apply when using a 2Volt - 120mA, mini solar panel (please don't ask for support to other types of mini solar panels).

R14* = 1 Ohm Metal Film, 1%
RV1 = Adjust to 2.7K

Using those values your solar irradiance sensor is able to give you readings up to 1500 W/m2, with considerable precision, however for better results further calibration, by slightly adjusting RV1, is recommended.
Under ideal conditions (a cloudless day, around noon in mid-summer) the solar irradiance measured by the WeatherDuino solar sensor should be similar to the theoretical maximum.
The theoretical maximum solar irradiance for any location at any day of the year can be found using the Apogee Clear Sky Calculator.

If you intend to use the Apogee SP-110 Pyranometer as solar irradiance sensor, then R14* must not be installed.

1.2 Measuring UV Index
Instructions below apply when using the UVM-30A UV sensor.

RV2 = Adjust to maximum value (10K Ohm)
RV3 = Adjust to minimum value (0 - 100 Ohm)

If you intend to use the VEML6075 as UV sensor, then RV2 and RV3 don't need to be installed.


2 - The JP1 jumper
The JP1 jumper must be installed only when using a FineOfset wind vane.

Example of a FineOfset wind vane, sold under several brands.
.jpg FineOffset_WindVane_250px.jpg Size: 31,07 KB  Downloads: 495


With any other type of supported analog wind vanes (like Davis 6410 or 7911), JP1 should not be installed.
For a complete list of Weather Instruments supported by WeatherDuino, please refer to this page: https://wiki.weatherduino.com/supported_...nstruments


3 - LoRa or OOK radio
The transmitter can operate with LoRa or OOK radios. Depending on which mode you will intend to operate your transmitter, there are some components that you may decide not install.

3.1 Operating in LoRa mode
OOK radio, VR2 (78L09F), C4 and C5 don't need to be installed

3.2 Operating in OOK mode
LoRa radio, IC1 and C2 don't need to be installed.

3.3 Radio Select Shunt
Depending on operating mode (LoRa or OOK) there is an small shunt (RCS) that should be done using a drop of solder.
  • For LoRa, put a drop of solder between the right and centre pads.
  • For OOK, put a drop of solder between the left and centre pads.

.jpg RF_Jumper_500px.JPG Size: 52,79 KB  Downloads: 485
]]> <![CDATA[Weather Station in New Mexico, US]]> https://www.meteocercal.info/forum/thread-2051.html Sat, 24 Jul 2021 15:43:09 +0000 Nmweather]]> https://www.meteocercal.info/forum/thread-2051.html
.jpg wind and rain small.jpg Size: 435,63 KB  Downloads: 391


It's mounted on the roof with a stand made of electrical tubing. 

I made a cart with a supplier based on the BOM for the 4Pro transmitter, while relatively familiar with electronics I am by no means an expert, if anyone has the time to review my order I would greatly appreciate it. My hope is that others can use the cart for their own orders, I added two of  the 915 mhz radio as I will need a second for the receiver. A couple of the items I had to use my judgement to get what I think is the correct equivalent part. specifically:
C6 - BOM calls for 50v but it looks like another 16v part like C5, C7, and C8
IC1 - I believe this the right part but not totally sure
IC2 - I believe this the right part but not totally sure
IC5 -  I believe this the right part but not totally sure, the part in this cart is a two channel
T1 -  I believe this the right part but not totally sure
VR1 -  I believe this the right part but not totally sure, this supplies 800ma at 3.3v but not a "...and 1A Low Dropout (LDO)..."
R14 - I don't see this one installed
RV2- I don't see this one installed
FANLED / TXLED - I ordered two of the same blue LED

Also I'm unclear what this is, don't see anything related to it on the BOM:

.png Screen Shot 2021-07-24 at 9.36.00 AM.png Size: 54,2 KB  Downloads: 392



I really appreciate any help or comments, also if there are obvious ways to save money, i.e. cheaper parts from the same vendor let me know and I can revise the cart to make it more useful for others, this is the link:

https://www.digikey.com/short/73nt5ntb

Thanks  a lot!]]>
.jpg wind and rain small.jpg Size: 435,63 KB  Downloads: 391


It's mounted on the roof with a stand made of electrical tubing. 

I made a cart with a supplier based on the BOM for the 4Pro transmitter, while relatively familiar with electronics I am by no means an expert, if anyone has the time to review my order I would greatly appreciate it. My hope is that others can use the cart for their own orders, I added two of  the 915 mhz radio as I will need a second for the receiver. A couple of the items I had to use my judgement to get what I think is the correct equivalent part. specifically:
C6 - BOM calls for 50v but it looks like another 16v part like C5, C7, and C8
IC1 - I believe this the right part but not totally sure
IC2 - I believe this the right part but not totally sure
IC5 -  I believe this the right part but not totally sure, the part in this cart is a two channel
T1 -  I believe this the right part but not totally sure
VR1 -  I believe this the right part but not totally sure, this supplies 800ma at 3.3v but not a "...and 1A Low Dropout (LDO)..."
R14 - I don't see this one installed
RV2- I don't see this one installed
FANLED / TXLED - I ordered two of the same blue LED

Also I'm unclear what this is, don't see anything related to it on the BOM:

.png Screen Shot 2021-07-24 at 9.36.00 AM.png Size: 54,2 KB  Downloads: 392



I really appreciate any help or comments, also if there are obvious ways to save money, i.e. cheaper parts from the same vendor let me know and I can revise the cart to make it more useful for others, this is the link:

https://www.digikey.com/short/73nt5ntb

Thanks  a lot!]]>