Matronics Email Lists Forum Index Matronics Email Lists
Web Forum Interface to the Matronics Email Lists
 
 Get Email Distribution Too!Get Email Distribution Too!    FAQFAQ   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups   RegisterRegister 
 ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 

HomeBrew Engine Monitor

 
Post new topic   Reply to topic    Matronics Email Lists Forum Index -> AeroElectric-List
View previous topic :: View next topic  
Author Message
andymeyer



Joined: 31 Mar 2015
Posts: 17
Location: SW MI

PostPosted: Sun Dec 01, 2019 6:10 pm    Post subject: HomeBrew Engine Monitor Reply with quote

So, A few years ago, a friend gave me an 8 channel EGT/CHT system that displayed on a small 2.8" screen that was stuffed in a 5"x5"x2" box. A pain in my EZ, but it gave me EGT/CHT. I added a panel meter to display MP.
Come the day of Arduino... I'm addicted, but a bit over my head in some of the electronics - doing my best studying data sheets, etc..., but would love a second or third set of eyes on what I'm doing. Overall plan - full fledged engine monitor. Cool

So far - DAQ in back by the engine - A Teensy 3.6 spewing serial data via a MAX3232 to the cockpit.
8 AD8495's to read the thermocouples - I went this way since my thermocouples are grounded. I almost went with the MAX31855, but that's not for grounded thermocouples.
2 analog channels to read the voltages from the Lightspeed ignition for MP and Timing. 0 - ~0.5V signals
1 PWM channel to read RPM from the Lightspeed (10V PWM signal.
1 voltage divider to read the 5V oil pressure (EOP) signal at ~3 volts...
1 resistor divider to read the oil temp (EOT) thermister or RTD... I have a westach sender right now, plan to keep it. http://www.chiefaircraft.com/wes-399ot.html
1 spare resistor divider for carb heat in the future.
2 spare 3.3v analog ins for future fun. Any ideas here?
The Teensy 3.6 uses the two long lines of headers to mount right on top of the base board... Skip a few pins on the left side to simplify routing...

This will send RS232 data up to the instrument panel to a Teensy4.0 driving 2 2.8" cap touch screens. I've already got the breadboard for the displays working. The Teensy4.0 will also collect fuel flow, air temp, Volts and Amps, and read aviation data from the GPS.
I have an air data computer (Pitot, Static and temp) that will spew serial to my Avidyne IFD540 and to the Teensy4.0 for fuel economy calculations, TAS, etc...

I designed the air data computer, but it was pretty basic. My magnetometer so far has been a fail - can't get it to calibrate. Confused I want to pull the trigger on this board, but would really appreciate any inputs that the collective expertise here may have. I'm way beyond myself on this one... I'm also more than willing to share my design and code if that's of interest.

I designed this in Fritzing - easy for a hack to learn. Started trying Upverter, but progress was slow so I went back to Fritzing.

Questions:
Is my ground plane right? Tried to split analog and digital...
Am I asking for trouble with any of my signal routing?
Resistor and cap values logical? Any reason not to use 1% resistors on a small project like this?
The 10uF power supply cap - tantalum? or is there a better option for this these days?

Files are located at:
https://drive.google.com/open?id=1Ue5_RDt7YqWEHsvDSzuea_owb4BEpKAi

Thanks!

Andy


- The Matronics AeroElectric-List Email Forum -
 

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?AeroElectric-List



JLCSMT_Sample_BOM1.xlsx
 Description:

Download
 Filename:  JLCSMT_Sample_BOM1.xlsx
 Filesize:  8.4 KB
 Downloaded:  12 Time(s)

Back to top
View user's profile Send private message
nuckolls.bob(at)aeroelect
Guest





PostPosted: Tue Dec 03, 2019 7:21 am    Post subject: HomeBrew Engine Monitor Reply with quote

At 08:10 PM 12/1/2019, you wrote:
Quote:
--> AeroElectric-List message posted by: "andymeyer" <meyerkc135(at)gmail.com>

So, A few years ago, a friend gave me an 8 channel EGT/CHT system that displayed on a small 2.8" screen that was stuffed in a 5"x5"x2" box. A pain in my EZ, but it gave me EGT/CHT. I added a panel meter to display MP.
Come the day of Arduino... I'm addicted, but a bit over my head in some of the electronics - doing my best studying data sheets, etc..., but would love a second or third set of eyes on what I'm doing. Overall plan - full fledged engine monitor.


An ambitious project . . . kudos.

The easiest way to get a sense of your
projects qualities is through the schematics.
ECB art doesn't tell us much at this
stage.

Quote:
So far - DAQ in back by the engine - A Teensy 3.6 spewing serial data via a MAX3232 to the cockpit.

<snip>


Quote:
I designed the air data computer, but it was pretty basic. My magnetometer so far has been a fail - can't get it to calibrate. Confused I want to pull the trigger on this board, but would really appreciate any inputs that the collective expertise here may have. I'm way beyond myself on this one... I'm also more than willing to share my design and code if that's of interest.

Schematics with values first . . .

Quote:
Questions:
Is my ground plane right? Tried to split analog and digital...

Not generally useful on small boards especially
since they eventually come together at Vss
anyhow.

Quote:
Am I asking for trouble with any of my signal routing?
Resistor and cap values logical? Any reason not to use 1% resistors on a small project like this?
The 10uF power supply cap - tantalum? or is there a better option for this these days?

chip tantalums are fine. let's see the road-maps-for-
electrons first . . .



Bob . . .


- The Matronics AeroElectric-List Email Forum -
 

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?AeroElectric-List
Back to top
andymeyer



Joined: 31 Mar 2015
Posts: 17
Location: SW MI

PostPosted: Wed Dec 04, 2019 6:23 pm    Post subject: Re: HomeBrew Engine Monitor Reply with quote

Well Bob, That's the funny thing. I got so frustrated at the schematic tools that I skipped that step, but I'll go back to it 'cause I know it's the right thing to do. Let me see if I can get something that's understandable.

Andy


- The Matronics AeroElectric-List Email Forum -
 

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?AeroElectric-List
Back to top
View user's profile Send private message
nuckolls.bob(at)aeroelect
Guest





PostPosted: Thu Dec 05, 2019 7:43 am    Post subject: HomeBrew Engine Monitor Reply with quote

At 08:23 PM 12/4/2019, you wrote:
Quote:
--> AeroElectric-List message posted by: "andymeyer" <meyerkc135(at)gmail.com>

Well Bob, That's the funny thing. I got so frustrated at the schematic tools that I skipped that step, but I'll go back to it 'cause I know it's the right thing to do. Let me see if I can get something that's understandable.

Andy

I suggest that a 'program' is not
necessary and, unless you're really
'salty' with one, clumsiness of
implementation gets in the way of
design deliberations.

Get a tablet of quad-ruled paper,
a #2 pencil, straight edge and a
'pink pearl' eraser.

Sketch your schematic in functionality
blocks. Download this drawing for
an example.

http://www.aeroelectric.com/Misc/9018-600D_DACard_P1.pdf

Here's the signal conditioning card for
a Arduino based DAS system. It took three
pages to define all the functions for an
8 channel i/o shield. Do your design in similar
fashion . . . push and pull the ideas around
on paper with a draw/erase capability that
is probably faster than a CAD program.

When the details are stacked up to a good stopping
point, scan the pages and post to the List.
Then folks here can begin to compare your
handiwork with their own knowledge and
experience for the development of suggestions.

A Pentel 0.9MM HB pencil and Pink Pearl are
my own first-line design tools.




Bob . . .


- The Matronics AeroElectric-List Email Forum -
 

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?AeroElectric-List
Back to top
Display posts from previous:   
Post new topic   Reply to topic    Matronics Email Lists Forum Index -> AeroElectric-List All times are GMT - 8 Hours
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum


Powered by phpBB © 2001, 2005 phpBB Group