New: PicoAPRS-Lite APRS Transceiver Module

PicoAPRS with GPS receiver

New Firmware V011 dated 29. January 2019:
On the developers website you can find the latest firmware for download.
Besides buffixes and new features the developer also included a game :) See the full changelog on the download site.

Flappy Bird on PicoAPRS

PicoAPRS now in Version 3!
Since June 2018 we ship the Picoaprs in version 3. This new version has the following modifications:

  • Even smaller and lighter! The case is slightly slimmer and slightly shorter, reducing the volume by about 1/4. This also requires a new holder (Pico-Clip).
  • V3 receives not only the GPS staellites, but also the GLONASS signals. The result is an even quicker fix of position and better accuracy of position than before.
  • New battery: Without cable, very easy to exchange. Now a standard sized LiPO battery from a digicam is used. The charger is also a new model supporting this new battery. Please check for the correct version "V2" or "V3" when purchasing a spare battery.
Antenna not included
PicoAPRSについての日本語の情報は こちら になります。

"Worlds smallest APRS transceiver with TNC" offers many applications. Matchbox-sized, built-in GPS receiver.

The transceiver can not only be used as APRS tracker and receiver for APRS data, but also as TNC (KISS protocol) for computer.
The graphical OLED display (128x64 pixel) shows received APRS packets such as position reports, APRS messages and status information.
When receiving position reports the distance and cardinal direction to the sender is shown.
Each of the four most recently listened in stations, including distance and cardinal direction as well as received messages are saved and can be retrieved via menu.

The own GPS coordinates are also shown, allowing the PicoAPRS to be used as a GPS receiver as well, for example for Geo Caching.
It's possible to save a fixed GPS position. This position is used when GPS positioning is not working. The fixed GPS position is then only used to show distance and cardinal direction of received stations. A speedometer is also included. You can choose to have your speed displayed as either km/h, mph or knots.

All handling is done with two push buttons. With the help of a versatile menu system the transceiver can be individually configured and operated without using a computer.
The device comes almost fully preconfigured. Just save the call sign and you're ready to go.
The transmit power is approx 1 Watt and can be switched down to 0.5W. The own position data is transmitted as a compressed MIC-E APRS message to keep transmit duration as short as possible. This also helps to save battery power. Of course received messages in compressed MIC-E can be decoded and displayed as well.

The built-in 850mAh LiIon battery allows operation up to 10 hours [1] depending on configuration.
The HF receiver can be deactivated to save a lot of power, the Pico-APRS then functions as a pure APRS tracker. To extend battery lifetime even further the GPS receiver can be turned on and off in programmable intervals and the display can be dimmed. While charging the charge current is being displayed. A buzzer is used for alarms and confirms button touches (can be turned off).

The PicoAPRS can now fulfill functions of a POCSAG pager. In contrast to a normal pager the device can even send an acknowledgement when receiving a message. This shows the sender that his message has been received successfully. Messages can be sent directly to other radio amateurs ion the APRS system, or even to E-mail adresses. A simple reply function allowes the use of pre-made standard replies. Just select "Reply", select the prepared text and send. Ready!

While en route you can send a link to your position on to your destination by e-mail. With this function the people you are visiting can easily see where you are and when to start brewing a fresh coffee. This works worldwide without a mobile phone system, without roaming bills, without a mobile phone. The own callsign including SSID is embedded in the link, the recepient just needs to click on the link.

The new tactical 'follow' function is helpful for example when skiing with a partner. Just select the callsign of the partner, select 'follow' and you will continously see the position and direction of the followed station. When receiving new position reports the display is updated automatically. Or you can use this function while driving in a convoy with multiple vehicles.

The built-in micro USB connector is not only used to charge the built-in battery and for upgrading the firmware, but also to use the tranceiver as a USB-GPS mouse or as a TNC at a computer. This allows you to set up your own APRS Digipeater or iGate in a breath! We will provide a guide for this in the near future. Via a menu you can choose wether the PicoAPRS should automatically turn on once connected to a USB power source. This is especially useful in cars when your power source is switched on upon startin the car.

The transmitter utilzes a 7-pole low pass filter to suppress unwanted harmonics. The main processor is well known from the Arduino world, it's an ATmega 1284p. The current software uses a little more than half of the available memory, this allows for a lot of further developments in the future.

The tiny size of just 33 × 56 × 18 mm is close to that of a matchbox. The weight (without antenna) is just 44 g. This is perfect to carry the Mini APRS Transceiver with you all thetime, whether on a hiking trip, on a journey with your bike or boat or even when skiing.

PicoAPRS Display

The Pico-APRS was developed by Taner Schenker (DB1NTO).

[1] Depending on how frequently the position data is to be sent, whether APRS packets are to be received, whether the GPS receiver should be switched off automatically when not in use, and how often the display can be switched off

  • Menu items (to be extended):
  • Device off
  • Recently listened in stations
  • Received messages
  • APRS symbol
  • GPS status and display of GPS data: coordinates, absolute altitude, Maidenhead (QTH) LOCATOR, GPS date, number of satellites, course
  • USB mode (AUS, GPS, TNC)
  • Save current position as "default position"
  • Transmit power (1 Watt / 0.5 Watt)
  • Send Beacon
  • Time zones for adjusted displayed time
  • MyCall, SSID
  • Receiver exchange ON/OFF (OFF = just tracker for sending position report)
  • Frequency
  • Autoclose (closes received messages after an adjustable time automatically)
  • Display timeout ("screensaver")
  • GPS power saving (ON/OFF)
  • Display contrast (low / high)
  • APRS comment text
  • Information display
  • Reboot

No charger or antenna included. Thanks to the standard micro USB connector, the charger of any newer mobile phone can be used for charging. Alternatively, charge with any USB charger or USB port of a PC. For suitable USB cables see accessories list.
Any antenna with SMA connector can be used as an antenna, for recommendations see our accessories list. The tiny device makes you want to use a tiny antenna as well, but small antennas have a comparatively poor efficency, of course, and we only have 1W of transmit power. When used in a vehicle, an external antenna is recommend, for example a magnet base antenna.

Order No.
PICOAPRS PicoAPRS APRS Transceiver 199.00 € Add to shopping cart In stock, shipped in 1 to 2 days.
PICOAPRSNOBA PicoAPRS, no battery 194.00 € Add to shopping cart In stock, shipped in 1 to 2 days.
Info freight charges
picoAPRS contains a LiPO battery which unfortunately is treated as a dangerous good, and thus will not be transported by the postal service office (= DHL in Germany). So, for overseas countries the product may be shipped by UPS only, with excessive freight charges.
To overcome the problem we offer the Product without a battery as well, for cheap shipment by DHL.
The batteries are available everywhere easily. For V.2 (up to may 2018), it is a standard LiPO battery for RC drones. Part no is 902540, for example used for Syma X5SW/X5SC quadrocopters. For PicoAPRS V.3 (supplied from june, 2018) it is a battery like NP-48 for Fuji Digicam
Link: Download of Drivers, Firmware (opens in new window)
Download: Bedienungsanleitung PicoAPRS V.2 (DE)
Download: Bedienungsanleitung PicoAPRS V.3 (DE)
Download: User Manual PicoAPRS V.2 (EN)
Download: User Manual PicoAPRS V.3 (EN)
Link: Changelog (EN) (opens in new window)
Download: Test report pico-APRS by Swiat Radio 12/17 (Polish)
Download: Test report pico-APRS by QST 9/2018 (EN)
Download: 1:1 printable picoAPRS paper model

Link: First Impression and Test Report (JP) (opens in a new window)
Download: Article about picoAPRS in CQ-JA Nov. 2017 (JP) (opens in a new window)


PicoAPRS Mount

PicoAPRS Mount PicoAPRS Mount

Mount for PicoAPRS. Can be attached anywhere thanks to the included Velcro strip. The USB port stays accessible.

Order No.
PICO-CLIP Mount for PicoAPRS V.2 15.80 € Add to shopping cart In stock, shipped in 1 to 2 days.
PICO-CLIP_V3 Halterung für PicoAPRS V.3 15.80 € Add to shopping cart In stock, shipped in 1 to 2 days.
Info freight charges

Recommend equipment and magnet base antennas

Equipment and magnet base antennas
Order No.
17023 DIAMOND SRH-805 equipment antenna, length 4,5cm 18.50 € Add to shopping cart In stock, shipped in 1 to 2 days.
17021 DIAMOND SRH-815S equipment antenna, length 15cm 21.00 € Add to shopping cart In stock, shipped in 1 to 2 days.
17037 DIAMOND SRH-771 equipment antenna, length 36 cm 13.50 € Add to shopping cart In stock, shipped in 1 to 2 days.
17022 DIAMOND SRH-36 equipment antenna, length 36 cm, very flexible 31.00 € Add to shopping cart In stock, shipped in 1 to 2 days.
20117.SMA DIAMOND MR-77S magnet base antenna, 4m cable, base 65mm diameter 36.00 € Add to shopping cart In stock, shipped in 1 to 2 days.
20119.SMA DIAMOND MR-75S magnet base antenna, 3m cable, base 30mm diameter 31.50 € Add to shopping cart In stock, shipped in 1 to 2 days.
20111.SMA No-name magnet base antenna, 3m cable 22.90 € Add to shopping cart In stock, shipped in 1 to 2 days.
40074.06 USB/Micro-USB cable, 60cm 3.90 € Add to shopping cart In stock, shipped in 1 to 2 days.
40074.1 USB/Micro-USB cable, 100cm 4.50 € Add to shopping cart In stock, shipped in 1 to 2 days.
42860 SMA quick release connector 7.90 € Add to shopping cart In stock, shipped in 1 to 2 days.
42854.02 Adapter SMA-plug(m)/BNC-jack(f), ultra short, black 11.40 € Add to shopping cart In stock, shipped in 1 to 2 days.
35051 USB battery charger V.2 8.50 € Add to shopping cart In stock, shipped in 1 to 2 days.
35055 Spare battery LiPO 3,6V/850mAh for Pico-APRS V.3 12.50 € Add to shopping cart In stock, shipped in 1 to 2 days.
35061 USB battery charger for LiPo Akku V.3 13.50 € Add to shopping cart In stock, shipped in 1 to 2 days.
Info freight charges

Here are more equipment antennas.

USB charger to charge spare batteries without the device.
A maximum of 4 batteries can be charged simultaneously, with charge control indicator. Requires a USB connector as power supply.

35051: USB charger
35051: USB charger side view
42854.02: Adapter SMA-plug(m)/BNC-jack(f)
Pico-APRS PicoAPRS Production
testing PicoAPRS PicoAPRS Functional test

Customer Feedbackto the PicoAPRS

A customer write in December 2016

From: ON8SD
    To: WiMo

   It was worth the waiting! PicoAPRS, the smallest APRS-transceiver in the world is working like a charm!
   DB1NTO had done a fantastic job! Next stop, trying to find a good antenna to get the most of the 1W
   output because this one has to become an emergency device while trailrunning !

PicoAPRS-Lite APRS Transceiver Module New


PicoAPRS-Lite: popular PicoAPRS' little brother.

A tiny APRS tracker weighing just 7.2 grams*!
Even though the PicoAPRS-Lite was developed with balloon flights with APRS payload (Pico balloons and stratosphere balloons) in mind, it can naturally also be used for many more APRS purposes.
Thanks to its small measurements of just 27.8 x 66.9 x 6.3mm this tiny tracker can, for example, be installed nearly invisibly in cars. This allows for APRS usage without annoying wiring in the car or too short antenna cables.
You can even carry the tracker around in your pocket!

An SMA antenna jack is offered separately since its weight of about 2 grams is an unnecessary extra load for the light Pico balloons. This is also the reason why the tracker is being delivered without a case.

Special functions of the PicoAPRS-Lite:

  • Automatic or manual frequency tuning on request. E.g. automatic for worldwide balloon flights.
  • In areas without APRS coverage and with automatic frequency tuning the ISS APRS frequency is used to be heard even in these situations.
  • Temperature and air pressure sensor. The values will be sent as an APRS comment in every position.
  • As an energy source a small solar cell with buffer capacitor can be used, as well as single-use or rechargeable batteries. Voltage range ca. 3.2 - 5V.
  • When using a solar cell the PicoARPS-Lite will stay in battery-saving mode use only about 0.1mA until the buffer capacitor has stored enough charge, then sends a beacon and will go back into battery-saving mode to recharge for another beacon if needed. Even with just one solar cell which supplies the buffer capacitor with just a tiny amount of current it can operate forever in sunshine! Ideal for a world trip with a balloon.
  • Even when using batteries the energy-saving mode will be used between beacon transmissions to extend the battery's lifetime.
  • Micro USB port for settings configuration with a terminal software.
  • Integrated GPS module with balloon mode up to 80km height, ideal for stratosphere balloons.
  • Transmission power configurable between 0.5 and 1W.
  • 7-pol lowpass filter to eliminate unwanted spurious emission.
  • Status LED
  • Firmware updates via USB possible. Future wishes of users and product improvements can be uploaded later.

Beware that this device has no voltage regulation!
When operating with a solar panel and buffer capacitor the service voltage will usually drop to zero at night. With sunrise the device will be operational soon again.
It's important that the tracker can be used with as little power as possible. A voltage regulator would cause a voltage drop which would be inconvenient during sunrise/sundown.
To limit the maximum operating voltage a beacon will automatically be transmitted when reaching about 5V in balloon solar mode to use up stored energy. Doing so the maximum operating voltage won't be exceeded even when the idle solar cell provides too much voltage.

*1) Weight without antenna jack, case or any energy source.

Optional accessories:

  • SMA jack for circuit board mounting, upright, with long thread, for single hole fixing.
    If the device should be in a case and used with a regular antenna.
  • Lithium polymer battery 3.6V/800mA, as well as compatible connector cable for an external energy source.
    Beware, the PicoAPRS-Lite has no voltage regulator for batteries! Never charge batteries via USB!
  • Small USB charger for 4 LiPo batteries max.

Available by the end of January 2019.

Order No.
PICOAPRSLITE APRS Transceiver module 139.00 € Add to shopping cart In stock, shipped in 1 to 2 days.
42907 SMA jack long, thread mount 7.40 € Add to shopping cart In stock, shipped in 1 to 2 days.
35051 USB charger with 4 battery connectors 8.50 € Add to shopping cart In stock, shipped in 1 to 2 days.
35052 Battery connector cable 3.80 € Add to shopping cart In stock, shipped in 1 to 2 days.
Info freight charges

PicoAPRS LITE goes to space

On 21. April a small version of the PicoAPRS will fly with an experimental rocket starting from Poland.

PicoAPRS Lite on RC Glider