eschrom
Well-Known Member
Outstanding DIY work you're doing there, Oahu. Best of success to you. Any chance you'd be willing to write up an instructable? After you work the kinks out, of course. ;D
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Oahu's X-ponder
- Thread starter eschrom
- Start date
wbpace
Well-Known Member
Oahu,
I see you are using a PIC with an 32 bit ARM Cortex. What software are you planning to use? Or are you rolling your own?
O'Bill
I see you are using a PIC with an 32 bit ARM Cortex. What software are you planning to use? Or are you rolling your own?
O'Bill
o'Bill ,
I think PIC is a 16 bit mcu on a different instruction set then an Arm chip, but yes its a 32 bit Arm Cortex M0 44mhz clock. There is no ready made software that I am aware, the code is written in C.
Eschrom,
I am not sure what the Instruct able would entail, PCB assembly? Most everything on the board is SMD and the board features lots of 8 mil traces the assembly would be better done by a pick and place machine. My intent is to have all the SMD stuff done by machine and reflowed at an assembler, the only thing left will be a few through hole components for hand soldering, things like switches and connectors.
I am assembling my boards by hand but thats pita and requires some practice.
My current Idea is to have a milled aluminum enclosure for the RF board then the digital stuff can live on the outside of the aluminum enclosure under 3d printed lid. Not sure that requires much instruction.
An instructable on how to do Microwave circuit design is called a textbook and I have no desire to write that much about the subject.
I think PIC is a 16 bit mcu on a different instruction set then an Arm chip, but yes its a 32 bit Arm Cortex M0 44mhz clock. There is no ready made software that I am aware, the code is written in C.
Eschrom,
I am not sure what the Instruct able would entail, PCB assembly? Most everything on the board is SMD and the board features lots of 8 mil traces the assembly would be better done by a pick and place machine. My intent is to have all the SMD stuff done by machine and reflowed at an assembler, the only thing left will be a few through hole components for hand soldering, things like switches and connectors.
I am assembling my boards by hand but thats pita and requires some practice.
My current Idea is to have a milled aluminum enclosure for the RF board then the digital stuff can live on the outside of the aluminum enclosure under 3d printed lid. Not sure that requires much instruction.
An instructable on how to do Microwave circuit design is called a textbook and I have no desire to write that much about the subject.
wbpace
Well-Known Member
Oahu,
You are correct, a PIC is not an ARM (is not a 68K, is not a PPC, is not a MIPS, is not a.. - I've worked on all of them, and more). I just took that from the header line of the google search (google atsamc21g18a). I know better and should have not used that mixed terminology - I just repeated the Google spew without editing. I've no excuse except to say mea culpa.
I wish you best of luck and will watch your progress with interest. It's a big task.
O'Bill
You are correct, a PIC is not an ARM (is not a 68K, is not a PPC, is not a MIPS, is not a.. - I've worked on all of them, and more). I just took that from the header line of the google search (google atsamc21g18a). I know better and should have not used that mixed terminology - I just repeated the Google spew without editing. I've no excuse except to say mea culpa.
I wish you best of luck and will watch your progress with interest. It's a big task.
O'Bill
Bill,
Guess you read the silk screen very carefully to lift the part number! I have 5 boards of the prototype(Minimum ordering quantity) showing up if you are interested in lending a hand on the Coding side that would be great, could send you the one of the extra boards. You would have to populate them, but that might not be an issue for you. I am working in the atmel studio IDE with their provided Software Frame work(library). I Still need to layout the RF front end, so I really will not be coding it till am done with the RF side. However writing the code to talk with gps on spi, reading the barosensor, user interface stuff, doesn't require the RF board.
There are two arm chips in this radio the ATSAMC21G and the ATSAMC21E, one for the main logic board the other for the panel mount display and user interface.
I think for all intents and purposes the Panel mount is ready to go and just needs programming.
Oahu
Guess you read the silk screen very carefully to lift the part number! I have 5 boards of the prototype(Minimum ordering quantity) showing up if you are interested in lending a hand on the Coding side that would be great, could send you the one of the extra boards. You would have to populate them, but that might not be an issue for you. I am working in the atmel studio IDE with their provided Software Frame work(library). I Still need to layout the RF front end, so I really will not be coding it till am done with the RF side. However writing the code to talk with gps on spi, reading the barosensor, user interface stuff, doesn't require the RF board.
There are two arm chips in this radio the ATSAMC21G and the ATSAMC21E, one for the main logic board the other for the panel mount display and user interface.
I think for all intents and purposes the Panel mount is ready to go and just needs programming.
Oahu
eschrom
Well-Known Member
Once again, I applaud you for the effort but isn't this more expensive than just buying one?
Nope, not by a long shot.
Just google what a Mode S transponder cost that meets the 2020 mandate. Some models require a separate altitude encoder and waas gps source, which adds cost to the complete solution. If you already have a Mode C transponder your can add UAT transceiver , those are significantly cheaper then a Mode S transponder. However you still need to have a Mode C transponder which are not cheap either. So to meet the mandate you either have to buy a Mode S transponder plus anything else it needs or a Mode C transponder plus a UAT transceiver plus the altitude encoder for the mode C. If you already own a Mode C transponder then a UAT is a pretty good deal. However if your Mode C is some King or Narco from the 70's and it kicks the bucket well the cost is going to suck.
I designed my version to have every thing in one box, WAAS GPS, Altitude Encoder, UAT receiver, and the 1090 transmitter. Its by no means inexpensive either there is not cheap way around 250 watt microwave transmitter, thats the bulk of the cost.
Just google what a Mode S transponder cost that meets the 2020 mandate. Some models require a separate altitude encoder and waas gps source, which adds cost to the complete solution. If you already have a Mode C transponder your can add UAT transceiver , those are significantly cheaper then a Mode S transponder. However you still need to have a Mode C transponder which are not cheap either. So to meet the mandate you either have to buy a Mode S transponder plus anything else it needs or a Mode C transponder plus a UAT transceiver plus the altitude encoder for the mode C. If you already own a Mode C transponder then a UAT is a pretty good deal. However if your Mode C is some King or Narco from the 70's and it kicks the bucket well the cost is going to suck.
I designed my version to have every thing in one box, WAAS GPS, Altitude Encoder, UAT receiver, and the 1090 transmitter. Its by no means inexpensive either there is not cheap way around 250 watt microwave transmitter, thats the bulk of the cost.
Hopefully Oahu will continue to make progress on a very cost effective solution to what can be a potentially very expensive mandate to comply with by 2020. The least expensive solution I have seen on the market is the Garmin GDL 82 which sells uninstalled for about $1,800. The GDL 82 has a GPS WAAS receiver, a UAT transmitter and through some clever engineering uses an existing Mode C transponder. Cost effective if one has an aircraft with a compatible Mode C transponder, not so cost effective if a new Mode C transponder has to be installed with the GDL 82. Oahu's solution should be a lot more cost effective.
Oahu, my hangar partner is somewhat of an electronic whiz as well; he is currently partnered in a venture that makes most of the drone autopilot modules. He has access to a board manufacturing plant as well, PM me if you want his contact information.
Mitch
Oahu, my hangar partner is somewhat of an electronic whiz as well; he is currently partnered in a venture that makes most of the drone autopilot modules. He has access to a board manufacturing plant as well, PM me if you want his contact information.
Mitch
The GDL 82 is does not actually use the Mode C transponder for anything, other then the squawk code. The Mode C signal passes through the device to the antenna with out any interference or alteration. All the GDL 82 does is transmits a separate signal on 978 MHz out the same Antenna, which is terrible from an efficiency stand point. Mode C and MOde S run at 1090 MHz and most antennas are tuned for that frequency.
