This is the master page for all of my Near Space Ballooning projects

• Bob - My first tracker, Arduinio Pro 328 3.3v, NTX 2 and uBlox MAX 6 on a Veroboard shield
• ProMini - My second tracker, Arduinio Pro Mini V2 328 3.3v, RFM22B and uBlox Max 6, currently dead bug style
• ProMini2 - My third tracker, Arduinio Pro Mini V2 328 3.3v, RFM22B and uBlox Max 6, currently dead bug style

A new series of trackers on my own PCB's, inspired by pAVA and such like.

• HabTrk V006 - B1 - V006 Board 1
• HabTrk V006 - B2 - V006 Board 2

• Launch 1 - Completed 01/12/2012
• Launch 2 - awaiting HabTrk for backup tracker
• Launch 3 - Mini launch using just HabTrk tracker

• Frequency - documentation of my own thoughts on frequency use

Frequency range legally available is 434.04MHz - 434.79MHz according to IR2030.

Point in time analysis using SDR and external collinear:

• 434.040MHz - Start of legal band
• 434.046Mhz - Weak interference
• 434.075Mhz - NTX2
• 434.078Mhz - Weak interference
• 434.099Mhz - Weak interference
• 434.110Mhz - Weak interference
• 434.112Mhz - Weak interference
• 434.121Mhz - Weak interference
• 434.127Mhz - Weak interference
• 434.169Mhz - Medium interference
• 434.267Mhz - Weak interference
• 434.320 to 434.330 - Strong interference
• 434.330Mhz - Weak interference
• 434.347Mhz - Weak interference
• 434.361Mhz - Weak interference
• 434.369 to 434.379 - Strong interference
• 434.375Mhz - Emergency Comms
• 434.392Mhz - Weak interference
• 434.475Mhz - Internet voice gateway, 25khz
• 434.500Mhz - Internet voice gateway, 25khz
• 434.518Mhz - Weak interference
• 434.525Mhz - Internet voice gateway, 25khz
• 434.550Mhz - Weak interference
• 434.581Mhz - Weak interference
• 434.600Mhz - Repeater input, 25khz
• 434.613Mhz - Weak interference
• 434.625Mhz - Repeater input, 25khz
• 434.650Mhz - NTX2
• 434.650Mhz - Repeater input, 25khz
• 434.675Mhz - Repeater input, 25khz
• 434.700Mhz - Repeater input, 25khz
• 434.725Mhz - Repeater input, 25khz
• 434.750Mhz - Repeater input, 25khz
• 434.775Mhz - Repeater input, 25khz
• 434.790Mhz - End of legal band

Thinking about frequency spacing, to be able to receive multiple transmissions with one dongle:

Typical RTTY bandwidth is 650Hz, we probably want at least 3,000Hz gap to keep audio spectrum separate.

Frequency drift research is very difficult, actual examples found are down at 1.1 or 5.7khz, advice is that they could drift 20khz. 50khz spacing seems a reasonable suggestion to allow for +20khz of one and -20khz of another.

We want to restrict the spacing to the FunCUBE Dongle bandwidth of 192,000hz, 50khz plus drift fits easily within this bandwidth.

Any questions you can get in touch with me at kevin a t unseen d o t org.