I thought I’d do a little summary for you on what’s cooking under the surface at the moment here in Finland while we are waiting for the flying season to slowly begin.
These have been very popular, looks like the good old DIY-spirit is truly alive and well! I’ve had a lot of contact with people both just saying their DIY-stuff works but also some messages saying things are not going so well.
There’s pretty much two scenarios for issues, one is regarding the Jeti Altmeter where I did the sensor with BMP180 sensor since that’s what was in my “million box”. Since BMP180 is updated to BMP280 everywhere in Ebay people are of course getting those, unfortunately there’s two main issues:
- BMP280 uses different I2C address (0x77 vs. 0x76)
- BMP280 really should be used with BMP280 library
This makes some frustrating moments with DIY-people since it seems to be a bit of a lottery if it works or not. Solution will come soon, I have ordered some BMP280’s from two different sources and I will make a separate program with identical functions for the Jeti Altmeter. This all should be done in about two weeks, my forst shipment of BMP280’s should be here quite soon.
The Jeti Hall RPM-sensor will get some add-on information at some point too. I have on the to-do list a day of internet search and datasheet-day. Reason is that omnipolar hall-sensors that work with 3.3V do not grow on trees. I have no plans on changing the actual sensor in my design since the omnipolar modle gives so rich possibilities but i will take into account some common or easily available bipolar sensors and explain the needed code-changes for that.
I’ve used Arduino Pro Mini as 8Mhz 3.3V version to all my sensors for some reasons, I happened to have some, they give 3.3V to other components like RFID-board and they are cheap to get as clones. Code and functions is of course straight compatible with genuine Arduino of same model but looks like many of you want to use Arduino Nano for easy PC-attachment since Nano has USB built-in where Pro Mini needs a FTDI cable.
For some reason people are having issues with Nano and getting it to identify itself to receiver. One reason might be the software serial library combined with custom speed of serial (9700baud) added with the fact that Nano is 16Mhz where Pro Mini’s I made all programs for is 8Mhz. So my guess is that timing is a bit off, receiver, especially REX-receiver, is quite picky on that point.
Once again, solution is on the way, my shipment of Nano’s will be here soon so I’ll do some testing and if need to be I’ll make own files for those who do not care that much about the size of sensor. nano is after all a bit bigger than Pro Mini.
DIY is not dead!
Quite many of these have been made according straight contacts, emails and forum messages and this really makes me glad. I’m happy to see that while stuff can be bought from manufacturers there’s still people who like to tinker and make stuff themselves.
I have planned a few in-depth tech articles too. At least one of them includes a bit more oscilloscope work, some of measurements are already done but quite a lot more needs to be done before story is ready.
Also if my ideas go as planned there will be some sort of reviews from somewhat not-so-usual angle soon, these depends also from some external decisions so these falls under category “maybe, and hopefully” at the moment.
There’s the annual Model Expo toy & model fair in Finland coming up soon so that’s three days there representing RC Heli’s with Finnish RC Heli association. We also have 4 flight shows per day there where I’m speaking non-stop so it will be quite busy this year. Finnish Speed Cup 2017 for RC-Helis with my Sleipnir speed-measurement system will have one practice event before summers five competition events that will start in the end of May, that needs to be prepared too.
Then there’s the traditional “four helicamps in four weekends” coming up by the end of May. This year it will be 2+2 weekends back-to-back with one “maintenance weekend” in the middle, might be needed with my flying style…
So, it’s getting busy, but hey, we always have evenings on the weekdays…
As always, if you have ideas on what to write about, projects you’d like to see done a how-to for or anything else, do not hesitate to contact!