2018-02-18

Premise

Wasn't sure if the RF4463PRO was going to be heard properly in the air.

Worried about attenuation due to chips being tuned for 433MHz.

Wasn't able to hit the city from roof like last time.

Decided to launch some helium party balloons with a simple transmitter and avr to drive it.

No GPS.

Two objectives:

• Confirm real-world receivers understand my transmissions from this new chip
• Confirm transmission range

Success. Many receivers understood. Max distance ~178 miles.

TX Details

Simple dipole made from wire, active element taped high on string, gnd low on string.

Quarter wave, 19" lengths.

Transmitted every 5 seconds a static message with incrementing sequence number.

1200 messages received before going offline.

No idea why or where (and did not care nor plan to care).

First: 2018-02-18 12:13:02

Last : 2018-02-18 14:09:27

So ~2 hours

It was a bad idea to transmit every 5 seconds. Used way too much airtime.

Balloon Lift

Balloons 13

Balloon lift 64

(avg balloon lift) 4.9

Payload weight 43.2

(free lift) 20.8

Results

It works.

Max range seen: 178 miles (est)

Extremes:

• DE - N3KNT-1 (178 miles)
• NY - KC2OUR-4 ( 47 miles)
• NJ - MAYLDG ( 96 miles)
• CT - EKONCT (128 miles)
• RI - N1LMA-15 (127 miles)