Chelmsford landing planned for SSDV Balloons

Image from the SUPER balloon launched by Dave Akerman M0RPI on July 12, 2014

434 MHz SSDV image from the SUPER balloon launched by Dave Akerman M0RPI on July 12, 2014

Radio amateur Philip Crump M0DNY plans a number of High Altitude Balloon (HAB) flights this weekend transmitting Slow Scan Digital Video (SSDV).

SSDV picture from a PIE balloon - Image credit Dave Akerman M6RPI/2E0LTX/M0RPI

SSDV picture from a PIE balloon – Image credit Dave Akerman M6RPI/2E0LTX/M0RPI

The launches will take place from Gilwell Park near Epping Forest and the balloons are expected to land around Chelmsford in Essex.

They are planned as part of the Gilwell 24 Scouts Activity event, taking place from 9am Saturday, July 12 through the night to 9am Sunday, July 13 in Gilwell Park. The plan is to monitor predictions/weather, prepare the payload, launch when convenient, then Philip M0DNY will chase, recover and repeat, up to 2 additional times.

The balloons are 100g hwoyees, and so are only expected to reach around 14 km altitude due to the weight, and increasing chances of wet landing for a longer flight. A Raspberry Pi is being used for the SSDV, and will store images as well as short but frequent video clips.

Due to tracker issues Philip may be flying a borrowed SUSF tracker on 434.613 MHz, replacing his one on 424.125 MHz.

The USB frequencies used will be
• 434.200 MHz – G24HAB – 600 baud SSDV
And either:
• 434.125 MHz – GILWELL24 – 50 baud RTTY
• 434.613 MHz – GILWELL24 – 50 baud RTTY + 300 baud TurboHAB FSK (SSB)

The 434.613 MHz tracker will alternate between 50 baud RTTY and 300 baud binary TurboHAB. To decode the binary error corrected format you need this decoder: , which has been updated since last time. To decode the binary protocol you first need to change ‘Encoding’ to BIN and ‘Baud’ to 300. Upon changing the callsign and position you need to press ‘Update’ for the new data to be used. It will be interesting to see the relative performance, the error correction should make most difference where there is noise or fading.

First launch is tentatively scheduled for 2pm BST Saturday. Philip will post updates on Twitter and #highaltitude. There will most likely be a live stream of the launches check

David Akerman M0RPI and Heston Blumenthal with balloon - Image credit M0RPI

David Akerman M0RPI with balloon – Image credit M0RPI

Dave Akerman M0RPI is also launching on Saturday between 10-11am from Ross On Wye. His balloon will be transmitting on three frequencies one of which will be Slow Scan Digital Video (SSDV).

$$SUPER: 434.450 MHz, 300 baud RTTY, 880 Hz shift, USB, 8, N, 2, SSDV
$$UAD: 434.480 MHz, Domino EX22
$$UAR: 434.475 MHz, 50 baud RTTY, 400 Hz shift, USB, 7, N, 1

There should be live video streaming on BATC.TV The chase car is M0RPI_chase:

The balloons should have a radio range of up to 700 km providing coverage over a large part of the British Isles and into Europe.

Listen to the Balloons via the Web

Radio amateurs Noel G8GTZ, Martin G8JNJ and Phil M0DNY from the Southampton University Wireless Society, have established an Internet accessible WebSDR receiver near Basingstoke in the UK. It has special helix antennas optimised for balloon and satellite reception in the 144 and 434 MHz bands and can be listened to from anywhere in the world. Listen using the WebSDR at

Online real-time tracking of balloons

See the received SSDV images on the web at

Beginners Guide to Tracking using dl-fldigi software

Slow Scan Digital Video (SSDV) Guide

To get up-to-date information on balloon flights subscribe to the UKHAS Mailing List by sending a blank email to this address:

Follow the launch day chat on the #highaltitude IRC channel at

The Chelmsford Amateur Radio Society have a new short training course for those wishing to become radio amateurs starting on September 4. To find out more speak to Clive G1EUC on
Tel: 01245-224577
Mob: 07860-418835
E-mail: training2014 at

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