The uMonitor kit

I must admit I'd waited for a long time for this kit to show up. I'd even looked forward to winter so I could finally get my chance to stop the aircraft building for a bit to try something else. Below are a few shots of how I got on.

uMon Kit

Once the box finally arived I did a quick inventory. What I noticed was a well organised kit with clear plain instructions. All the parts were clearly labeled and where required the correct precautions were taken to avoid component damage.

uMon Main halfway


Here is the main PCB halfway through.

The only thing I did differently was to solder the integrated circuits to the PCB. The kit supplies high quality sockets to make it easier for people not used to hadling such devices. Since I've lost count many years ago of how many chips I've soldered, I skipped the sockets.

uMon CPU


This is the complete CPU board. Note the sockets for the EPROM on the left.


Anti static precautions are required to handle the IC's but everything is explained in detail in the assembly manual.

uMon Final Construction


Final assembly of the unit.. Everything fits very nicely.

uMon 1st Powerup


Applying power to the unit for the first time !! HOORAY !!


Don't know if its fault free yet but it doesn't look too bad.

uMon in Panel


I thought I'd better see what it loos like in the panel. (Sigh)

I have to burn it in now (hot and cold endurance testing) then calibrate the instrument. So did I enjoy it.. you bet... and would I recommend it.. definately..   

18th Jan 2004

I decided that I wanted to be able to store engine parameters like a flight recorder would for use during my test flying so I thought I'd set to and design an interface for the uMonitor. The uMonitor has a serial output capability but it is proprietary in that it isn't a standard RS232 interface used in computers so what I needed to do was design an interface. First I read the info on the serial port and wired it apropriately in order to enable the serial output. (See the Rocky Mountain info sheet) then I needed to decide how to interface to it. I decided I would program a PIC chip since it seemed the easiest way to adjust things until I got it working. Once I got the prototype working I designed the PCB for it and got Express PCB in the USA to make a couple for me, below is the result.

If you would like to do this also, I would be happy to help. One word of warning is that if you intend running your uMonitor on the bench, ensure you wire the Oil pressure port to ground so that your Tacho doesn't keep running adding bogus flight time.

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This is the very simple schematic.. click the piccy for the PDF of it and click HERE for the bill of materials.
Next came writing the code for the main microcontroller (16F84). If you want to see the code click HERE for the pdf of it. If you are set up to program PICS and have MPLAB click HERE for the source code.

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After I tested it all and got it working it was time to make a prototype PCB. and make that work before getting on to the PC software.

As fate would have it, I had an engine failure in my aeroplane now. If I had been just a bit quicker I could have used the save parameters from this project.   Hopefully I won't need it again when I've done it.

Early interface

The first crack at the PCB. A couple of minor stuff-ups but it works fine. The next version of board will be better.
As far as the PC software goes, I have now got working software that stores each parameter every update (Every second). It uses MS Access so that the data can be easilly displayed in any form or even exported to other applications. I will one day wite some software for the IPAQ PDA to show graphical representations of the data. I'm too busy test flying right now though. Might be a good winter project.

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