digitech

My Feedback: (10)

Digitech Electronics JetCat text info screen development.

Developed by Sandor Kruise (Digitech Electronics BV / Carsten Groen)
Some Highlights:
This Unit Developed by us, was specially designed for JetCat users worldwide using JetCat engines or ECU
The Unit is a very lightweight 32 characters display back-lighted.
The unit can be placed inside your model, it is very small.(The unit will be approx 53 x 20 mm (the active area in the display is 36 x 10 mm). )
The unit can be directly connected to your ECU , or the JetCcat LED I/O interface
The display will show you critical info on “rolling mode” info screens.
NO need to connect the large GSU anymore except if you want to program something.
The Small info screen can be connected all the time.
Your model can stay with the cockpit closed and you can see what is happening on startup !.

The display will show the following:
Last off condition
RPM
RPM currently commanded by the user (via your transmitter)
EGT in Celcius
Current pump voltage
Total Fuel left in Metric ML or U.S Ounces
Current fuel consumption pr. minute ( Metric ML or U.S Ounces)
Current state during startup (PreHeat, LearnLO, etc)
Plug Failure (kero and gas)
Battery Voltage.

Developing :
We want from you as our customer, some feedback about the different rolling screens we have made.
We based the screens on what we as pilots often would like to see during a start/run:

On boot up of the JetCat ECU it will show you the following as show in the picture Below.

Boot-screen with version of software is shown for a few seconds.
Then it will show Last off condition, Battery voltage, and ambient turbine temperature.
It will show this, until a start attempt is done.
As soon you start the turbine the info screen will change to show :
Temperature of turbine , Battery voltage , RPM , and starting sequence.(it will show also if your plug is failed or other critical info)

As soon it is in running mode, the screen will change again to show the following 2 screens (they will move forth and back in about every 3 seconds)
Screen 1
Pump voltage , Battery voltage , Fuel left/ Fuel consumption by ml/minute (millilitres)
3 seconds wait
Screen 2
RPM (read from sensor / RPM commanded by the throttle. / Pump voltage

If you now switch turbine off , the screen will change into idle mode (same as when the system was powered on)
It will show Turbine temperature , Battery voltage , last Off condition of engine (RC off, fuel fail etc)

Since the unit is produced as we speak, we can still change the software and make changes to the firmware.
We are open to suggestions if you have any idea’s, we might have overlooked something to show on the screens etc.
We discarded the idea of showing the Failsafe count , since personal I never seen one in the first place.
But we can enable this again!
Also info about typical cable length is appreciated.
We can offer the unit in different packages.
RTR Ready to Run
DIY
We made the solder pads to connect the cable to the ecu extra large so that the user CAN Re-solder a shorter or longer cable to the unit.
The unit is so small that a Female RJ connector would simply be to big to mount on the PCB.
The display itself is directly connected to the PCB board and does NOT have to be connected by the user it is ready made
The unit itself is protected against DIY modellers who have sometimes a Brain fart and solder the positive to the negative J
Don’t worry the unit is protected against that and will simply wont work!.
It will not blow up your ECU , by connecting it the wrong way.

About firmware
We are thinking about also optional delivering a programming data cable , but could be difficult for users to DIY (firmware upgrade)
Another option could be Fixed screens but can be set by users by holding a combination of buttons on the original GSU from JetCat
It will NOT be a open source firmware , simply because it is copyrighted software and we spend lots of time on developing and purchasing prototype boards and parts.

We are looking forward to info on the subject and hope it will be a nice topic and we hope to make this unit the way the people want it to be.
Below are some pictures and a PDF for you to look at.
Below you will see the changes we will make after user input.

EDIT :

Added : Fuel left and Fuel consumption will be added also in U.S Ounces mode showing Ounces a minute ( eu and US version)
Added : Failsafe screen Enabled again
Added : add GPS readout to the display also, so that when you land, and the display detects that a GPS is connected to the ECU, it will show max speed, travel distance etc etc
And maybe the same if a pitot tube is mounted
EDIT: Fuel restriction detection (Pump voltage will blink if the value is higher then last known setting to detect possible fuel problems) if restarted the new value will be stored as the "new"max voltage.

Harley Condra

My Feedback: (4)

Pretty neat!
What is the projected unit price?

Some of us would prefer fuel consumption in ounces/minute, and the failsafe icon and count.
Also, the RJ-11 connector on the PCB would be more foolproof than soldered wires.

digitech

My Feedback: (10)

Hi Harley

the price will hopefully be around 50 euro,s incl local vat for EU customers that are vat charged
and about 55 usd in outside europe.
the failsafe count and icon is no problem we can enable this screen again and will be shown at startup screen and will change to last user off condition
as for the Imperial mode yes good idea and we can enable this inside the Program will maybe be user selectable.
as for the RJ connector , this is difficult as i mentioned the unit is so small the RJ connection would be bigger then the thickness of the total unit.
but it will have pull protection , the pics you see are prototypes.


Next Opt : GPS info
we will also enable this feature also , it will detect if the unit is attached and will show gps info

Carsten Groen

Thinking also about showing (in idle mode) the last max pump voltage, that way when you shutdown the engine, you can have a look at it, and make a "mental" note of it, if it goes up between a number of runs, you have some kind of restriction in the fuel supply
It's good to get a small "brain storming" about this, there is probably things that we/I did not think about in the first place!

PS: The final unit will be one complete unit, the flat cable shown in the photos will be "hidden" between the two printed circuit boards.
The unit will be approx 53 x 20 mm (the active area in the display is 36 x 10 mm).
The display is transreflective, very easy to see in sunlight (and has green backlight also for the "night flyers" )

Carsten Groen

Harley,
if you want fuel in oz, would you also like the EGT in Fahrenheit ?
(in other words, if a user wants ounce, does he also want F instead of Celcius ?)

readyturn

My Feedback: (9)

The temperature should remain in celcius in my opinion, as that is really a standard for engine operation.

Fuel flow in U.S. ounces verse that of Imperial would make more sense for those of us in the U.S. or just keep it in ML.

The product looks good and should be a convenience at the field.

Harley Condra

My Feedback: (4)

No, I'll go along with readyturn on that one.

digitech

My Feedback: (10)

Noted and edited in the first post

we can let the user decide for Celcius or Fahrenheit.
or if more people vote for celcius we will leave that alone

lov2flyrc

My Feedback: (24)

Nicely Done!

digitech

My Feedback: (10)

Thanks nice to see some positive news sometimes .
i might even come over on your stand at florida jets and have our picture taken together.

gruntled

I am feeling the love.

lov2flyrc

My Feedback: (24)

LOL... I welcome it!
Business is Business but I'll still buy you a beer ;-)

digitech

My Feedback: (10)

funny thats what i said when opening a letter from my ex wife about monthly payments

BaldEagel

Congratulation a nice looking product, any idea when it will be available, I'll have two please.

Mike

digitech

My Feedback: (10)

Cheers
we are hoping April.

Selleri

Sweet work guys! [8D]

So you would have to disconnect the screen if you want to connect the GSU?
Just thinking from aesthetics point of view, when you've gone to the trouble of hiding everything except the JC I/O interface behind panels.
Maybe it is just best to get a Y splitter after the ECU so you can connect both at the same time?

Carsten Groen

As I'm currently waiting for a GPS unit for the ECU, I have no real data to look at.
So, can any of you with a GPS tell me if the G-force is of any use ? If it is calculated from GPS data I would guess it has not too much value, but I might be wrong !?
Trying to decide how much info should be shown in idle, too many screens is not ideal from a user standpoint....

Sverrir, exactly

olnico

Hi Sandor,

I always check the following significant data after a flight and write it on my flight log:
Max RPM in flight
Min RPM in flight
Max EGT in flight
Start EGT
Max pump voltage in flight

Min and mx RPM are very important to check the turbine operational enveloppe. If min RPM was too low in flight, I then increase it in the limits menu.
If max RPM in flight goes over the limit I then reduce it in the limits menu similarly.
Max EGT is very significant of the combustion cycle. If it goes higher than the limit, it is typically because the acceleration parameters are too high in the limits menu.
Start max EGT tells me about the ramp/gas parameter
Max pump voltage has already been covered by Carsten...

The evolution of these data with time also tells a lot on the turbine health and when to send it back for service...

If these data could be made available after a turbine shutdown, it would be really good.
You could also supply the unit with a word file containing a flight log including the above data and a short explanation note on how to use it...

GSR

My Feedback: (145)

Excellllllllent!!. Put me down for three.

Carsten Groen

Good input Oliver!
I'm currently looking at changing/adding screens to the device, my only concern is that there simply is too much data.
So it all boils down to try to minimize the number of screens, but still be able to "deliver" the most important data to the user, without having to wait for a high number of screens to pass by

JetCatJimmy

Is there a reason why a larger screen wasn't chosen?

Carsten Groen

Jimmy,
the reason was primarily that the unit should be small, so it could be mounted in dashboard, or anywhere else in a plane.
Also it should be possible just to "stick" it ontop of the ECU if no other place was available.
Even though the display is small, it is very easy to read, with a very high contrast.

JetCatJimmy

Yes, it's very legible. I was thinking of pixel real estate. If there were more pixels there could be more info, but I didn't realize it would be mounted in the plane. Thanks!

Carsten Groen

Ah yes, by "size" I only thought about physical size
But you are right, more pixel enables more info, the problem quickly becomes cost, this one is a mix of relatively low price, good quality, and small size, so it's, as always, a tradeoff.

JetCatJimmy

Definitely understand there. It's a LOT of information to "mash up".