Transponders for Dummies.....me. Need explanation please.

Joe Pires

star hoarder
So I see a lot of information about adding ADSB to an aircraft that already has a Mode S transponder. I do not have any transponder yet would like to become compliant by 2020. I live and fly within Class B airspace, I know I am supposed to have Mode C but I do not. So is there an extremely compact reasonably inexpensive way to add all 3 in a single upgrade. Remember for dummies..no jargon, no assumptions about what I am supposed to know please.

If not is there an efficient way to add Mode S with adsb, starting from no transponder.
 

EdL

Comm Rotor Gyro, ASEL
Joe

Take a look at the Trig TT22 transponder, TN72 GPS source, and TA70 GPS antenna, $2569 bundled at Aircraft Spruce. You can save about $300 off that if you use a generic, much smaller GPS antenna for $20 on Amazon instead of the TA70. That’’s the setup I have, including the generic antenna, and it works well and is 2020 compliant. I think the Garmin GA25 antenna, for $29 at Spruce, would also work and be a name brand. Heads up that you’ll need to swap out the antenna connector if you use a non-Trig one but that’s easy. I’m not sure I’ve seen a less expensive route for Mode C/S plus ADS-B Out that’s 2020 compliant.

/Ed
 
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You do not need mode S unless you are going to flying in class A airspace (Above 18,000 ft) or in certain foreign airspace.
That will likely changes in the near future as the world tends to do whatever the USA does.

Mode C will suffice. for the Transponder requirement.

The ADSB requirement can be legally implemented with a Mode ES transponder or a UAT transponder.
Mode ES is Mode S with the Extended ADSB Squitter add-on.
Mode S (ES) meets the legal minimums with ADSB-Out and can deliver ADSB Traffic IN.
Modes S will require a separate UAT Reciever if you want to receive the Weather products.

The UAT variation gives you ADSB-Out plus ADSB-In including ADSB -Traffic IN and the Weather Products including Live WX Radar, METARs, SIGMETs, Winds aloft, and more.

If you are starting from scratch consider that a Sandia STX360 can supply a Mode C transponder Plus UAT ADSB-in and Out in a single box for ~$3200
Their STX360R is the same package minus the panel display for ~$2800 if you will be using an EFIS Glass panel display instead of an iPad.

The $20 GPS Antennas are Not ADSB compliant.
They do not meet the WASS and RAIM position source requirements of 14 CFR91.227.
 

Flowsleeve

Junior Member
I also find myself in the same situation. Believe I am looking at purchasing the iFly 740 Bundle. Then I just need to find a Mode - C transponder to couple with it.
Does anyone have a better suggestion?


Thanks,
Chris
 

eutrophicated1

Designated Acronym-Nazi
I'm really glad that all those who replied to the request for information listened so well. I had to duck out of the forum for a while so I wouldn't be hit by flying acronyms and sundry jargon. You all did see that Joe specifically requested, "No Jargon", right?
 

HighAltitude

in transition
Chris, the package you posted is different than the Huey chief package posted. He is showing a combo transponder/ADS-B system.

Joe,
I would wait for that package (echoESX). Since you are in a controlled airspace, then you are stuck with a trig or sandia transponder and a package like flowsleeve posted if you can't wait a month or two for the ESX.
 

EdL

Comm Rotor Gyro, ASEL
Just an additional thought or two:

Re the Sandia (and the uAvionix, for that matter), make sure the price includes an acceptable GPS. The Trig bundle does. Also, the Sandia appears to be the rectangular panel mount type - do they have one that will fit a 2 1/4” hole?

Re uAvionix, I think they’re a good up-and-comer but their primary focus is drones. Sandia and Trig have certified stuff and (much more) airplane background. Plus I fell for their “coming this fall” with the updated Pingbuddy a few years back and it never made it to market - plus, again because of their drone activity, that particular one would have only displayed ship-to-ship traffic and no ATC-based traffic or even weather.

/Ed
 

Joe Pires

star hoarder
I have been flying in Mode C area for a decade without one....so I can wait months easily..but am I right that the ECHO ESX will not meet the requirement for mode C?
 
eutrophicated1;n1137805 said:
I'm really glad that all those who replied to the request for information listened so well. I had to duck out of the forum for a while so I wouldn't be hit by flying acronyms and sundry jargon. You all did see that Joe specifically requested, "No Jargon", right?
Yes, we saw that.
Just asking about ADSB is using the jargon.
It would be unreasonable to ask everyone to type "Automatic Dependent Surveillance-Broadcast" every time they referred to ADSB which is properly abbreviated "ADS-B".

Explaining what ADSB is and how it works could easily require a few thousand words just to get through the basics.
All of this information is already available from a multitude of sources on the internet.
We like Joe, but he is going to need to at least get himself up to speed on ADSB by doing a little research on his own.

This is like wanting to build your own GPS receiver from scratch asking how GPS works in simple enough terms so that anyone could understand it.
GPS and ADSB are not simple systems and there is not going to be a simple answer.

His summary question was, "... is there an efficient way to add ... ADSB, starting from no transponder."?

This is the information, in as simple a form as we can get it to, that he is being provided.

Joe,
Do want a bare minimum but legal ADSB OUT only system, No traffic, No weather?
Or do you also want ADSB IN with the additional data available in flight?

The ECHO ESX will meet all the ADSB requirements, a Mode ES Transponder (ADSB Out) plus UAT ADSB-IN.
It is currently in "Coming Soon" status. Not yet available.
 
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Joe Pires

star hoarder
Actually my question includes that I am flying in airspace that requires a Mod C Transponder. So I meant to ask if it was not clear on how to become fully compliant.
 
Joe Pires;n1137844 said:
Actually my question includes that I am flying in airspace that requires a Mod C Transponder.
So I meant to ask if it was not clear on how to become fully compliant.
Transponders come in 4 basic flavors.

Mode A ... Squawk and IDENT.
Mode C ... Mode A Plus Altitude.
Mode S ... Mode C Plus TCAS Collision Info, ICAO Code.
Mode ES ... Mode S Plus ADS-B (Extended Squitter)

Modes C, S, and ES all meet the requirements of Mode C.

You can't buy a new Mode A Transponder anymore, so any Transponder will meet the Basic Mode C requirements for Class B airspace today.

The ADS-B OUT function is an extension of the TCAS Collision avoidance system.
To meet the minimum ADSB requirements you will need to transmit basic Mode C plus UAT ADS-B out Data ... Or Mode ES which incorporates the ADS-B Out Data.

The Mode C or ES transmission is the beacon that allows other aircraft to see your location.
You are not required to receive the ADS-B data but without it, you will be blind in seeing approaching traffic or weather.

Mode C or better will allow Airliner TCAS systems to alert the pilots to your presence.

Basic mode C will only inform a TCAS equipped aircraft that you are within a specified mile range.
Your Altitude will be known but your direction will not. "Traffic 2 miles, 5700 ft."
The distance is based on how strong a signal is received Air-to-Air, so it is not very accurate.
2 miles could be anything between 1 and 4 miles.

ADS-B will allow everyone to know what everyone else is doing in great detail.
"Propeller Traffic, 11 o'Clock, 2 miles, SouthWestBound, Descend through 5700 ft. at 70 kts."
 
Transponders come in 4 basic flavors.

Mode A ... Squawk and IDENT.
Mode C ... Mode A Plus Altitude.
Mode S ... Mode C Plus TCAS Collision Info, ICAO Code.
Mode ES ... Mode S Plus ADS-B (Extended Squitter)

Modes C, S, and ES all meet the requirements of Mode C.

You can't buy a new Mode A Transponder anymore, so any Transponder will meet the Basic Mode C requirements for Class B airspace today.

The ADS-B OUT function is an extension of the TCAS Collision avoidance system.
To meet the minimum ADSB requirements you will need to transmit basic Mode C plus UAT ADS-B out Data ... Or Mode ES which incorporates the ADS-B Out Data.

The Mode C or ES transmission is the beacon that allows other aircraft to see your location.
You are not required to receive the ADS-B data but without it, you will be blind in seeing approaching traffic or weather.

Mode C or better will allow Airliner TCAS systems to alert the pilots to your presence.

Basic mode C will only inform a TCAS equipped aircraft that you are within a specified mile range.
Your Altitude will be known but your direction will not. "Traffic 2 miles, 5700 ft."
The distance is based on how strong a signal is received Air-to-Air, so it is not very accurate.
2 miles could be anything between 1 and 4 miles.

ADS-B will allow everyone to know what everyone else is doing in great detail.
"Propeller Traffic, 11 o'Clock, 2 miles, SouthWestBound, Descend through 5700 ft. at 70 kts."
Awesome info Bill!
I learned more from that than sifting thru reams of online classes, but watch out for the acronym nazi. His shuffleboard game might be over and his computer time reinstated. :)
 

Tyger

Active Member
Uncle Willie;n1137849 said:
Transponders come in 4 basic flavors.

Mode A ... Squawk and IDENT.
Mode C ... Mode A Plus Altitude.
Mode S ... Mode C Plus TCAS Collision Info, ICAO Code.
Mode ES ... Mode S Plus ADS-B (Extended Squitter)

Modes C, S, and ES all meet the requirements of Mode C.

You can't buy a new Mode A Transponder anymore, so any Transponder will meet the Basic Mode C requirements for Class B airspace today.

The ADS-B OUT function is an extension of the TCAS Collision avoidance system.
To meet the minimum ADSB requirements you will need to transmit basic Mode C plus UAT ADS-B out Data ... Or Mode ES which incorporates the ADS-B Out Data.

The Mode C or ES transmission is the beacon that allows other aircraft to see your location.
You are not required to receive the ADS-B data but without it, you will be blind in seeing approaching traffic or weather.

Mode C or better will allow Airliner TCAS systems to alert the pilots to your presence.

Basic mode C will only inform a TCAS equipped aircraft that you are within a specified mile range.
Your Altitude will be known but your direction will not. "Traffic 2 miles, 5700 ft."
The distance is based on how strong a signal is received Air-to-Air, so it is not very accurate.
2 miles could be anything between 1 and 4 miles.

ADS-B will allow everyone to know what everyone else is doing in great detail.
"Propeller Traffic, 11 o'Clock, 2 miles, SouthWestBound, Descend through 5700 ft. at 70 kts."
Some additional info re the above: There are two possibilities for ADS-B "Out". It can be broadcast on either 978 MHz UAT (using TCAS) or 1090 MHz (ES) via a transponder. Mode ES just uses 1090 MHz. Ground stations pick up ES "Out" signals; these stations then rebroadcast the data for ADS-B "In" on aircraft so equipped. My understanding is that 1090 ES "Out" data does NOT go air-to-air, except to TCAS aircraft that have been modified to also process 1090 ES signals. So, two Mode ES equipped aircraft will NOT "see" each other unless they both have ADS-B "In" AND are close enough to a ground station to receive "In" data therefrom. Also, ground stations usually only broadcast the data for "In" when they are actually receiving "Out" data from aircraft in the area.

Importantly, to meet the "Out" requirements for a GPS source, your GPS receiver must be permanently installed (i.e. not a portable), and also be WAAS enabled. That is, the satellite position information must augmented by WAAS ground reference stations (https://www8.garmin.com/aboutGPS/waas.html)
 

eutrophicated1

Designated Acronym-Nazi
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Hueychief replied
09-07-2018, 12:27 AM
Transponders come in 4 basic flavors.

You're so right, chief, I'm also a "master computer systems engineer", with specialties in 5 major programming languages, 5 operating systems and DBA on 4 major DBMS's , and I can throw a boatload of acronyms on you in a heartbeat. Yet I'm also experienced enough to know the importance of proper documentation practices on all this stuff. Hence my continuing efforts to improve the "Gremminger" terms and acronym file.
 
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