SM7PNV's blog

Hi all.
I just released my latest low power, low cost WSPR transmitter.
This one has a built in GPS with built in antenna and is optimized for low current consumption and weight.
It can be powered from a single LiPo or from USB.
It cost only 39$ and operate on a single band as set with a low pass filter (sold separately).
Any band from 137kHz to 70 MHz
More info here : https://www.zachtek.com/product-page/wspr-tx-mini-transmitter

Hi all.
I just released an expansion card to my WSPR-TX_LP1 transmitter.
It expands the transmitter with four switched low pass filters.
With this combo the transmitter forms a standalone WSPR transmitter with on-board GPS that can do band hopping on four or more bands.
It is possible the lowest cost multiband WSPR transmitter available today. And it's Arduino based with open source.
I hope you find it interesting.

Hi.
I just released my new WSPR Desktop transmitter.
It is an open source Arduino based transmitter just like the previous one.
This one comes built in a box with four low pass filters and covers either 137kHz-3,8MHz or 7-18MHz or 21-50MHz depending on what model you order.

Configured from a PC software but will operate standalone using it's built in GPS for time keeping and position.
Powered from 5V USB so it suitable both for the shack and on the road or hike.

Hi all.
As a follow up to my WSPR receiver I have just released my standalone all band WSPR transmitter with built in GPS for the radio amateur experimenter.
It is built to be both simple to use and to be a platform to be expanded from for the experimenter.
Some quick features:
1 Standalone operation, no PC required for operation.
2 Works on any Ham band from 136kHz to 70MHz
3 Is powered from 5V.
4 Pre-built and tested except for the output Low Pass filter that needs to be built by the user.

Hi.
Go here :https://www.zachtek.com/single-post/2018/06/08/First-WSPR-RX-Customer-pu...
to read some more on my WSPR receiver but also for some observation on the effect of the local noise level for WSPR reception.

73
//Harry

Hi all.
I just released my WSPR Receiver for sale on my Webshop.
It is a complete one-band receiver built in box trimmed and ready to use.
Use this instead of tying up your regular Ham tranceiver for receiving WSPR.
Just plug in between Antenna and computer, can even be powered from a free USB port.

It takes about 0.4Watt of DC power, has a 10ppm crystal, about -127dBm (0.1uV) sensitivity measured for a 3dB S/N ratio in 500Hz bandwith.
It is frequency calibrated against my Rubidium standard before delivery.