Raspberry Pi QRP TX Shield for WSPR on 20 Meters
Nowadays, one of the most impressive QRP modes is Joe Taylor, K1JT's WSPR (pronounced "whisper") mode. WSPR stands for "Weak Signal Propagation Reporter." Programs written for WSPR mode are designed for sending and receiving low-power transmissions to test propagation paths on the MF, HF and recently, UHF bands. Users with Internet access can watch results in real time at wsprnet.org.
The QRPi board (or shield as referred by the community today) is an inexpensive way of turning a Raspberry Pi single-board computer into a QRP transmitter.
Traditionally, a LPF removes harmonics from a transmitter output, but leaves any broadband noise intact. With the QRPi board design the harmonics are filtered by a LPF, and the broadband noise is filtered by a BPF.
To protect the clock generator output stage of the Pi, a buffer amp is provided for isolation. This also provides a boost to the TX signal.
So join the group of Whispering Raspberries on 20 meters by ordering a TAPR 20M-WSPR-Pi today.
The QRPi (20M WSPR-Pi) comes to you assembled and tested.
Pablo, WA6RSV, alerted us to the fact that not everyone realizes what a Raspberry Pi is. He said "one week ago I thought a Raspebrry Pi was a dessert! (I like apple pie!). Nobody explained to me that it is a normal computer just like your Mac or PC . You can use it just like a windows PC to browse the internet, write an email etc....The concept is as follows 1) you buy it and you plug in a monitor, usb mouse and usb keyboard. 2) If the Micro SD does not have the OPERATING system (Like windows or OSX in MAC but for this contraption it's called NOOBS/Raspbian) you go get it at https://www.raspberrypi.org/ and copy it into the MicroSD which is also the hard drive/ram ) After installing the operating system then it will work like a NORMAL computer with everything including the built in WIFI (if a Pi 3) will work."
Note to international customers. This product (if ordered alone) will be shipped via letter post for $17.00, not the amount calculated by the website. The checkout page will show the incorrect amount, but it will be corrected manually during the order processing by the TAPR Office.
The price for the 20M WSPR-Pi is:
$ 29 US for members of TAPR
$ 29 US for non-members+ shipping/handling if applicable.
A note regarding email addresses: When checking out please use an
email adress other than @earthlink.net, @hotmail.com, @live.com,
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ALSO There is a problem with Chrome inaccurately reporting that the connection is insecure when you are attempting to complete your order. We suggest using a different browser to place the order.
Both problems are being worked on, sorry for the inconvenience.
Shipping and Handling
Shipping and Handling within the US will be by USPS Priority Mail.Note to international customers. This product (if ordered alone) will be shipped via letter post for $17.00, not the amount calculated by the website. The checkout page will show the incorrect amount, but it will be corrected manually during the order processing by the TAPR Office.
International shipping costs are calculated as closely as possible. If the actual cost exceeds the estimate by more than $10.00, TAPR will contact you to get approval for the additional funds. TAPR uses insured Priority Mail International, unless the purchaser requires something else.
Documentation20M WSPR-Pi (QRPi) software installation guide for different HAM TX modes
The TAPR 20M-WSPR-Pi project team is:
- Steve Bible, N7HPR, project manager
- Zoltan Doczi, HA7DCD, designer
- John Koster, W9DDD, logistics
20M WSPR-Pi at the 2015 ARRL & TAPR Digital Communications Conference