The ZL1SIX Ocean Floater

13 months free drifting in the South Pacific Ocean




An ocean going marine buoy containing a GPS and QRP-Labs Ultimate3S based transmitter. This project is intended to drift in the Pacific Ocean at the mercy of the tides, currents and wind directions while sending its position, battery voltage and temperature information via HF radio telemetry in WSPR and JT9 modes.

It transmits once per hour on the 30 meter Amateur Radio band. The receiver 'dial frequency' required to decode the digital signals is 10.138700 MHz USB (the normal 30m band WSPR frequency). The WSPR trail is near the top of the WSPR waterfall segment, and the JT9 signal is found about 150 Hz higher on the waterfall.


00:00 UTC 14 May 2016 - departed New Zealand from Opua Marina on board yacht Windflower
21:00 UTC 17 May 2016 - released at Maidenhead locator RG93SQ and drifting in the Pacific Ocean


ZL1SIX Ocean Floater ZL1SIX Ocean Floater


Daily update as at 00:00 UTC 25 June 2017: the position after 403 days in the ocean was QH64OW
Direct line change over the last 24 hours: 28 km drift at 251 degrees, average speed 1.17 km/hr
Direct line change from the drop off point: 3003 km at 289 degrees, average speed 0.31 km/hr
(apparent speed is slow due to doing loops following the wind patterns as well as the ocean currents)
Link to 'Nullschool' ocean current map at the Floater's position on 25 June 2017 at 00:00 UTC


ZL1SIX Ocean Floater


Ocean Floater JT9 Telemetry Ocean Floater JT9 Telemetry

Ocean Floater Battery Cell Voltage
The black curve is the manufacturer's capacity test result for a fixed resistance load, but the boost-inverter regulator ICs in the Ocean Floater will cause a steady increase in the current drawn as the supply voltage drops, thus the Floater's battery bank will discharge faster towards the end of its life. The JT9 telemetry reading "BAT" is now indicating that each 0.01 volt drop is occurring in about a day (as of late March) rather than every 2 days in Feb, every 4 days in Jan, and every 6 to 7 days during the third quarter of 2016.

Link to a text file of JT9 decodes received from 01 Jun 2017 onwards
Link to a text file of JT9 decodes received from 01 Apr 2016 up to 31 May 2017
Link to a text file of JT9 decodes received from 01 Feb 2016 up to 31 Mar 2017
Link to a text file of JT9 decodes received from 01 Dec 2016 up to 31 Jan 2017
Link to a text file of JT9 decodes received from 01 Oct 2016 up to 30 Nov 2016
Link to a text file of JT9 decodes received from 01 Aug 2016 up to 30 Sep 2016
Link to a text file of JT9 decodes received from 12 May 2016 up to 31 July 2016
Link to the last 20 WSPR reports of 'The Floater'
Link to 'The Floater' voyage archive, technical details and project build photos

JT9 decodes will be appreciated via e-mail to zl1rs@yahoo.com

Many thanks to the following who have contributed in some way to this project:
- VK2FAK, VK2EIK, ZL2ABN, E51WL, VK4RV, ZL2VF, K4COD, W3BH, VK5EI, ZL3CX, KL7L, W7CSD, VK3WE, VK3ZYC, VK3NFI, VK3KCX, VK5KJP, VR2UIF, AK4AT, VK2CMP, VK4ALF, VK4EHT for JT9 decodes
- Hans G0UPL ... for the excellent QRP-Labs kits and inspiration via his Voyager ideas
- The ZS boys ... for ideas from their similar project at the SARL forum (may need to register?)
- Andy VK3YT ... for the PCB with GPS and high efficiency inverters
- John & Lyn Martin of the Island Cruising Association for releasing the Floater from their yacht "Windflower" and their newsletter item (3.1MB pdf download) about the Floater
- to the several people who provided encouragment and moral support!