edit: BTW did you manage to get it working?
BTW I don't know if anyone would be interested in this, but I have found that the RF22 library is not compatible with timer based hardware servos. Very weird and hard to debug. It is because the interrupt driven read function takes too long, messing up servo PWM timings. I had to modify the library quite a bit, but now I have hardware servos! If anyone else have problems with the servo library I'll let you know what to change.
I'd be interested in buying a booster pcb from you (same layout as Melih for the same chip), maybe if you could design it in a way that the resistors, caps, diodes, etc would be of a bigger size, for easier diy work...Do you manufacture these pcbs by yourself?
Can you upload your modifyed library or explain here what to change? Did you solved the glitches issue with this mod?
Quote from: Dfidalgo on Apr 12, 2012, 01:18 pmte]Edit: Important notice, please make sure that you can find a 5V source on your radio, this board does not have a voltage regulator for the arduino, so you can not power it direct from your TX battery. Well, my TX is a Graupner MC-19, I think that a LM7805 can solve the problem dont? Anyway, I do intent to use your tx uhf with a joystick that generates the ppm signal from another arduino (details here: http://www.ianjohnston.com/content/index.php?option=com_content&view=article&id=30:project-rc-ppm-trainer-port-joystick) I have done this on my homemade console that you can see here at work:http://www.youtube.com/watch?v=wIUw7Lfdme4The joystick will be a old but cool "Top Gun" , and a pair of old T2m rudder pedals, all for FPV obviously.
te]Edit: Important notice, please make sure that you can find a 5V source on your radio, this board does not have a voltage regulator for the arduino, so you can not power it direct from your TX battery.
Yeah except I really don't know much about RF design... If I tried to make one of those high power amps it would probably catch fire!
The joystick will be a old but cool "Top Gun" , and a pair of old T2m rudder pedals, all for FPV obviously.
No need to worry about that since at would be runing it at 1/7 of its total output power and in such conditions you dont even need a heatsink for the chip..
One step at a time, let me get this simple board working properly first!
In the meantime I'd like to ask you, which vreg could be a suitable replacement for the one Melih uses - mic5205...I read the datasheet and saw it has a really low dropout voltage or something like that..Is there any other which has a low dropout voltage but a higher maximum current?So you use LM1117?Regarding Melihs design besides powering the atmega and rfm22, does anything else use power (maybe the driving of the servos? and if so do they use such a small amount)? Because that mic5205 has a small max current..Thanks!
The RF22 only draws 85mA at full power, plus maybe 20mA for the atmega. Also the transmission only happens in quick bursts so it's not always on. The mic5205 should be plenty, since servos are powered separately from the BEC. I think any regulator will work as long as the drop out voltage is not much more than 1V, obviously lower is better to prevent brownouts.
Thanks! you gave a very clear answer ...Why does flytrons TX module have 2 vregs, mic5205 and a LM2937?
What you think about a integration of the RFM12BP with your circuit in the future? Seems to be very similar to rfm22 but with 500mw. It is possible without modifications on your code?