Some quick features:

1: Standalone operation, PC required for configuration but not for operation.

2: Works on any Ham band from 136kHz to 70MHz

3: Is powered from 5V. 250mA

4: Pre-built and tested except for the output low-pass filter that needs to be built by the user.

5: Comes with built in GPS module and included external GPS antenna.

Timing and Maidenhead position is automatic from the GPS network.

Take it camping, move it to another QTH, use it mobile.

6: Includes an Arduino Pro Mini with open source software.

7: Does band hoping, can transmit on all bands from 137kHz to 70MHz or on just a few, you decide.

8: PC Software to configure the transmitter over USB.

Low-pass filters sold separately

The WSPR-TX LP1 works on any Ham band from 136kHz to 70MHz and is powered from 5V. Once you have set up your call-sign it will operate independently indoors or outdoors with minimal requirement of interaction from the user. There is no need to have it connected to a computer, no need to set the time or to interact with it in any way. The WSPR-RX_LP1 takes care of everything needed automatically for you.

The GPS provides the timing necessary to ensure that the WSPR transmission is occuring at the correct time. The GPS also provide the position information needed to calculate the Maidenhead code that is transmitted. This is a great feature as it means the users don’t have to know the Maidenhead grid before getting on the air. This can be very convenient if you take the transmitter to a new location or use it in a mobile application.

The output power around 300mW is in my opinion just perfect for WSPR operation. With a dipole antenna it will give you continent coverage most of the time but when the conditions are favorable it will give you trans-continent contacts so at this power level it easy to see how the daily conditions change. The input power requirements are 5V 100mA at idle and 250mA when transmitting. This makes it possible to use a laptop computer, phone charger or a USB Power pack to power it in mobile or stationary operation mode. What better way to test out your portable antennas than to stick this in your backpack with a USB power pack and try out different antennas or mobile QTHs?

Advanced but not high cost, minimal assembly required by the user.

To keep kost down and to minimize the amount of version I need to build and keep in stock I have not populated the Low Pass filter on the output. The buyer will have to purchase it separately and build it to complete the transmitter (or use an external filter). Everything else is built, calibrated and tested. See the shop for Low Pass filter options.

For more information including links to the Source code and Schema - see the documentation page.  Link to documentation page

Link to PC Software for configuration

The product comes with the board built and tested and an GPS antenna with 3m cable. Low pass filter not included.