The WSPR Desktop transmitter is a standalone multi-band WSPR transmitter with built in GPS for the radio amateur/experimenter. Some quick features: Standalone operation, PC required for configuration but not for operation. For transmission on a variety of HF Bands (2-5), based on model and user-choice. Is powered from USB. Comes with built-in GPS module and includes external GPS antenna with long cable for easy installation. Use the PC configuration software to set up your call-sign and band-choice and after that it can operate in standalone mode. Timing and Maidenhead position is automatic from the GPS network.

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

Needs only 5V 250mA so can be powered from a phone charger or USB power pack. Contains an Arduino with open source software.

Software and Schematic is published on documentation page. Available in three models. Model Low for bands 2190m and 630m

(136kHz and 474kHz)

Model MidPlus for bands 160m, 80m, 40m, 30m, and 20m (1.8MHz, 3.5MHz, 7MHz, 10MHz and 14MHz)

Model HighPlus for bands 17m,15m, 12m, 10m and 6m (18MHz, 21MHz, 24MHz, 28MHz and 50MHz)

Once you have set up your call-sign it will operate independently indoors or outdoors with minimal requirement of interaction from the user. 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 200 mW is 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? The product comes with an external GPS antenna and a USB cable but without a power adapter.



The PC configuration software is available for download form this web or GitHub.