Gender
Male
About
Location
Kenmore, WA
About Me:
Science enthusiast since old enough to drool ;) Electrical engineer by profession - avionics design. Been flying R/C since junior high. Built my own R/C radio in high school. Now building gas turbine powered F-18. Fly electrics, nitro, slope and thermal gliders. Wish job didn't take so much time away from my hobbies or I'd be building and flying more models.
Please tell us a bit about your UAV interest
Very interested in building an aircraft with autonomous ability to stabilize itself and navigate. Would enjoy attempting to build from scratch but time doesn't allow.
Hometown:
Seattle
Activity Feed
"If you were really going to go the home-made USB cable route, CAT-5e would be a good choice. Here's some rated to -40C. Not sure about price but probably fairly cheap: …"
"Well, USB needs one twisted pair for each direction. If you can't find an off-the-shelf outdoor type, maybe you could buy the indoor type and just use the electronics by replacing the cable with two silicone twisted pairs. I do see an indoor one…"
"Hi Thomas,
I'd think you would want to mount the modem on top of the pole and run data & power over the 60 feet (using a $30 active USB extension) rather than the coax because losses can be quite high. Try this calculator -…"
I'd think you would want to mount the modem on top of the pole and run data & power over the 60 feet (using a $30 active USB extension) rather than the coax because losses can be quite high. Try this calculator -…"
"Hello, anybody still here? I still have an old APM 2.6 and want to know how to add these analog channels in the flight code and the MP code.
Thanks,
Dan"
Thanks,
Dan"
"Larry, are you still around? It looks like you were able to add some analog channels by changing the AP code but what about Mission Planner? Didn't you have to change it too to tell it where and how to display the data? Is this info documented…"
"Interesting. Thanks"
"Hi, since you've got the RC link working, how is the latency? Have you had a chance to fly with it yet? Scott W said:
Thanks. I tried various settings last night and could never get them to talk, so I guess I'll give up for now too. 900x to 900x…"
Thanks. I tried various settings last night and could never get them to talk, so I guess I'll give up for now too. 900x to 900x…"
"Thanks for the info, Kent!"
"Hmmm ... I wonder if Seppo would take a 900 as a trade-in on a 900x ;-) Kidding! "
"Hi ID,
A good thing about these modems is that they use spread spectrum whereas GSM is narrow band. When a spread spectrum receiver de-spreads the incoming signals, narrow band signals are significantly spread out and therefore reduced while the…"
A good thing about these modems is that they use spread spectrum whereas GSM is narrow band. When a spread spectrum receiver de-spreads the incoming signals, narrow band signals are significantly spread out and therefore reduced while the…"
"Seppo, a couple other questions - I assume encryption will only be available on the "+" version, true? And is there any impact on the throughput?
Thanks,
Dan"
Thanks,
Dan"
"Hi Seppo,
Yes, a long time - but good to hear the news! Over the years, I've purchased 3 RFD900s from you and wanted to know if the Telem + PPM passthrough is a firmware update. My modems are all RFD900, not RFD900+, if that makes any…"
Yes, a long time - but good to hear the news! Over the years, I've purchased 3 RFD900s from you and wanted to know if the Telem + PPM passthrough is a firmware update. My modems are all RFD900, not RFD900+, if that makes any…"
"Yes, that's true - if they're too close to each other and running at higher power, the receiver front end can be over-driven, causing distortion and corrupting the signal. I always ran mine at lowest power when in the house and kept them around 10…"
"You're right about the cap installation, James.
If there's too much voltage drop when the modem transmits and the voltage spikes below something like 4.9V, it may upset it. You cannot tell just by using a voltmeter - you need an oscilloscope to see…"
If there's too much voltage drop when the modem transmits and the voltage spikes below something like 4.9V, it may upset it. You cannot tell just by using a voltmeter - you need an oscilloscope to see…"
"Hi Carl,
I had something similar with the RFD900s. It turned out to be the voltage drop during each transmit burst. I had to add a 100uF cap right at the modem because the supply wires were a little small for the distance I ran them. Have you tried…"
I had something similar with the RFD900s. It turned out to be the voltage drop during each transmit burst. I had to add a 100uF cap right at the modem because the supply wires were a little small for the distance I ran them. Have you tried…"
"Hi Carl,
I've never added a special ground plane. The cable shield acts as one half of the antenna so that, although it's called a monopole, it's really a dipole. If the antenna and cable are mounted so that they are in-line, the radiation pattern…"
I've never added a special ground plane. The cable shield acts as one half of the antenna so that, although it's called a monopole, it's really a dipole. If the antenna and cable are mounted so that they are in-line, the radiation pattern…"
