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Multi-Mode Transmitter for Balloons

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Multi-Mode Transmitter

MODES• Hellscreiber• RTTY• DominoEX• SSTV• CW• APRS (soon)

• Onboard GPS

• In/Out Temp

• Battery monitor

• 1 W on HF

• 0.3 W on VHF (FM or SSB) Frequency Agile from 3.5 MHz to 148 MHz

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MMT schematicA

A

B

B

C

C

D

D

E

E

1 1

2 2

3 3

4 4

(REMOVE R14 for pass ive)

ANT 1 is PASSIVE (REMOVE if active)

Jump if TTL GPS

to Garmin GPS

Vin

GND

Vout

U6Vin

GND

Vout

U712

J3

C9 C10 C11

+3.3+5V+12V

C12 C13 C14 C15

D3

12

J4 D4

2-A2GPS232

2-A2GPSINV

2-A2GPSTTL

Inventek GPS1 2 3 4 5 6 7 8 9

18 17 16 15 14 13 12 11 10

U8

4.7k

R9

+3.3

0.1C6

+3.3

JP2

1

2

3

JP3

1234

J6

0.1

C7

33

R10

33

R11

27pC8

27pC16

1

TP1

1

TP2

R12

R13

C17 C18

123

J7

27pC19

33nH

L5

+3.3

0

R14

ANT1

1 TP3

TXB

TXA

RXB

RXA

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MMT schematicA

A

B

B

C

C

D

D

E

E

1 1

2 2

3 3

4 4

GPS

123 4

56

16.386M VCXO

U3

27262524

188

16

151319

14

1211107

652321

203

2228

CY8C29466 U4

+3.3

+3.3

+3.3

16

1213

3

1

211

14

15

4 CY22393U5

R1 R2 R3 R4

+3.3

C4

R5

R6

12345

J2

1

2

3

JP1

R7

R8 LM61

1 2 3

U1+3.3

2N3866A

Q1

L1

L2

+12V

C1

123

J1

+12V+3.3

1-E3GPS232

1-E3GPSINV

1-E3GPSTTL

1 2 3 4

5 6 7 8

ASDX015A24R

U2+5V

L3

C2 C3

1

2

J5

C5

L4

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Multi-Mode TransmitterInventek GPS

- Built-in helical antenna- Battery backup- For hot starts <1s- TTL or RS-232 outputs

MMT-XMT

- Multi Mode XMT

-Can be used with any GPS (TTL or RS-232)- Serial output for Zigbee or Maxstream 9Xtend

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MMT Hellscreiber transmission• On/Off keyed mode

• 8.163 msec per pixel

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DominoEX mode• MFSK mode

• 18 tones

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dl-Fldigi • UKHAS mod called dl-FLdigi for uploading data to SpaceNear.us server

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Spacenear.us/tracker website

Displays positions decoded by dl-FLdigi onto a Google Map with chart and telemetry display box

- Designed by members of the UKHAS group

- Ground stations receiving telemetry are shown as towers

- Parachute comes out during descent

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Spacenear.us/tracker website

- Shows landing prediction in real-time (light blue target)

- - Can also upload chase car position directly to server via a wireless cellular link

Telemetry must be uploaded in the following format:$$callsign, sequence, time(UTC), lat, lon, alt(m), sats, batt, temp*<cksum>

$$WB8ELK,128,17:25:00,3441.03,-08554.20,26771,08,8.52,-9*7F

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Camcorders for balloons• Hobbypartz $59 thumbdrive camcorder

Tachyon XC helmetcam

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915 MHz telemetryMaxstream (Digi) 9Xtend

- 1 Watt output- 9600 baud or 115k baud- Long range with yagi on ground

- Up to 100 mW out- 900 and 2400 MHz versions- Great for wireless comms

between payloads- With a high-gain yagi it’s possible to directly link up to the balloon during flight

Digi XBee Pro XSC

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915 MHz telemetry

- Serial data from the MMT-XMT is sent to the XBee Pro for payload to payload comms or directly to the ground

- Ground station end showing XBee Pro mounted to the back of an 8 dB patch antenna

Digi XBee Pro

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915 MHz telemetry

- For improved range and

better pattern directly below the balloon you can use a “Nanowheel” antenna by Olde Antenna Labs (sold by www.hamtv.com)

- 900 MHz rubber duck shown for size comparison

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Remote control your ground station• Logmein.com

Control your radio with:

Fldigi

Ham Radio Deluxe

MixW

MultiPSK

Remotely log

Onto your

Computer via

Logmein

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Hardware control – Iobridge.com • Controls relays and sensors via Ethernet/Web

connection

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Hardware control – Iobridge.com • Internet-controlled AZ/EL Rotor via the Iobridge interface

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Field Day Balloon 2010

- Predicted a landing on top of the Huntsville Amateur Radio Club’s Field Day site

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Field Day Balloon 2010

Huntsville Amateur Radio Club members watch as the balloon parachutes down directly across their field day site

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Field Day Balloon 2010

Missed landing on the HARC Field Day site by 0.75 miles

Landed right in the middle of Lady Ann Lake

Field Day location

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Field Day Balloon 2010

A conveniently placed kayak saves the day