Hello,
I'm the official spokesman (and solitary member) of the Delta V Factory team.
Just a quick introduction to where this team/I stand.
I registered for the prize last November, and I've finally come up with some sort of near final design I'll probably test soon.
It's along the lines of most of the other teams, a rockon/ballocket, the balloon being a hydrogen filled weather ballon (about 2 kilo lifting ability), followed by two rocket stages. First rocket stage will give the satellite the altitude (aiming for 110-150 km), second will give it the velocity. Both are spin stabilized. After ascending to around 80 000 feet, the rocket is released from the balloon, and a "rocket belt" fires on the outside producing tangential thrust and spin. After the spin stabilized first stage takes the contraption to 110-150 km, the thing is de-spinned by a yo-yo type device like those used on early (real) satellites. The now slowly spinning contraption is tilted by the firing of a small tip rocket so while spinning it changes its inclination. Once a magnetic field detector determines it's pointing in the right direction and an accelerometer determines it's at the right inclination the last stage separates, fires another spin inducing rocket belt, and then ignites.
The final stage is a metal can shaved down to reduce weight, covered with wrapped carbon fibre, a pvc base and a nozzle, and a tiny transmitter. It's in a similar vein to the Wikisat team in that respect. The entire thing, empty, will weigh in at around 12 grams, and it'll have 600 grams of propellant, giving us a mass propellant ratio of 50. The propellant for everything is solid magnesium ammonium nitrate composite propellant, and with a (theoretical, anyways) isp of 230-240 s, in theory it'll give us orbital velocities.
The transmitter will be powered by a button cell, that'll load up a supercap which will discharge into a LCR circuit, modulated by a varicap, producing a beep on a VHF marine frequency every 20 seconds or so. The idea is that any receiver with access to vhf marine frequencies should be able to pick up the signal for tracking, or at least with something like a Yagi antenna to boost the signal. Also with an elongated polar orbit, it should be in the line of sight over much of Europe and parts of NA atleast for part of the orbit, making verification of a near impossible feat that much less difficult. I may throw in a thermistor to modulate the power output, if natural radiative heat dissipation doesn't prevent the temp from varying too much.
Anyways, I hope to do some static tests soon to characterize the propellants, as well as to see if the rocket can actually fire without blowing up instantly. Then it's testing the transmitter, and finally I'll fire the thing entire thing from the ground. If all goes well, I was hoping to try directly for the prize without any further intermediate testing. I figure the chances of anyone succeeding are so remote that extensive testing will only help marginally anyhow.