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I'm at the head-scratching phase of looking at the panel space available on my Onex. Are any of the currently available 'magic boxes' (MGL, Dynon, etc) capable of supplying transponder, ADS-B as well as radio and the other functions?

Ed
N???NX
Since military paint schemes are popular, and the Air Force had the Blue Canoe, I might paint it in dessert colors and call it the Khaki Kyak.
Just east of Graceland

Ed -

The answer is: Sort Of!

If you are referring to EFIS systems, most of them do not actually contain a radio or a transponder *inside* the main system. However, both MGL and Dynon units can easily integrate with a reasonable assortment of radios & transponders, allowing you to operate them via the EFIS unit.

For example, my MGL iEFIS Discovery Lite controls my Trig Mode-S transponder (which will be ADS-B compliant when I add the certified GPS in a year or two), and it also controls my MGL radio. For safety/redundancy, I still mounted my radio in the panel (so I can control it if the EFIS has a problem); but the Transponder is in the baggage area and has no panel-mounted controls other than the EFIS.

Dynon gear works very similarly, and although they might not have quite the same budget price-point as MGL their equipment is very very nice (I live near Dynon HQ and know folks there). There's a bit more "polish" put into their stuff - for example, I had some RFI issues with my MGL EFIS and in talking with my Dynon acquaintance he mentioned how Dynon had those issues in the beginning, but now designs and tests extensively to avoid that sort of thing.

Setting up this kind of centralized control requires ~4-6 extra wires to be run, but its not hard. There's plenty of information out there on which radios & transponders work well with each manufacturer, if you decide to head in this direction. And you can always ask questions here!

--Noel
Sonex #1339
(first flight waiting on my Turbo to be rebuilt)

P.S. Here's a photo of my panel. The main instruments you see are the Discovery Lite, an MGL ASX-1 (backup airspeed/altimeter instrument), and the V6 radio. To save panel space, the new MGL radio model can be remotely mounted (i.e. no separate control-head on the panel). https://flic.kr/p/21TkcYs

I agree with everything Noel says. I would add that MGL offers a "uAvionix EchoUAT ADS-B IN/OUT 2020-Compliant Package" which satisfies the 2020 ADSB out requirements. (The package also includes ADSB in functions.) I'm strongly considering installing it. The price is right at $1,400.

-- Michael
OneX N169XE
MGL Explorer iEFIS w/ Sandia transponder

At Airventure 2018 I looked at Garmin, MGL and Dynon. The 7” Skyview SE from Dynon is the front runner right now for my Onex. It is an econo version of their Skyview system.

NWade wrote: an MGL ASX-1 (backup airspeed/altimeter instrument)

Do you need separate pitot/static lines and a separate pitot tube for this B/U instrument? Or can you split the lines somehow?

Unless you have a fully redundant electrical system with separate buses I would think hard about relying on the ASX-1 as a backup instrument. I had a voltage regulator go bad on my aerovee and take out the EFIS. I was very glad to have a backup airspeed indicator that was not reliant on any power to work. To answer the question, yes it can be tied into the existing pitot/static lines with some T fittings.

Keith
#554

Keith -

You're right to point this out as a potential failure mode. Personally, I don't like the idea of a voltage regulator frying *anything* in my panel! That's why I use the Bob Nuckolls over-voltage protection circuit (sold by B&C Specialty). Given the number of voltage regulators that seem to have failed on various Jabirus & AeroVees, it seems like cheap insurance and a prudent precaution.

As for the ASX-1 - a major reason why I like it is that it has a back-lit display and displays both Alt & Airspeed. This is important to me because the most-critical time for me to need that information is if I lose my primary EFIS at night. (During the day I am comfortable with my flying skills - as an experienced sailplane pilot - to be able to set the aircraft down without reference to instruments, if necessary).

Lastly, I can power the ASX-1 with a switch and a 9V battery. It makes for a simple wiring job, and I can simply swap the battery out every time I give the airplane its annual condition inspection. I personally use a SPDT switch to enable it to run from main power or the 9V; but you could easily use just the 9V to isolate it from the main bus and only use it in emergencies (the 9V should give you a few hours of run-time).

And yes, David, you can simply use a "T" fitting on the lines and run them to both instruments.

Enjoy,

--Noel

Noel, thanks! T-split is simple.

Brilliant idea with the 9V battery and switch.

Sorry if this is a simple question, but for Engine probes (oil temp, oil press, CHT, EGT) can you also split all those lines to go to backup instruments? It's difficult to find things on this but I'm sure I'm not using the right terminology in my searches.

dtibbo wrote:Sorry if this is a simple question, but for Engine probes (oil temp, oil press, CHT, EGT) can you also split all those lines to go to backup instruments? It's difficult to find things on this but I'm sure I'm not using the right terminology in my searches.

No, most temperature probes are thermocouples that rely on a specific level of resistance in the probe and the wires leading to them (which are usually a very specific type of wire). For that reason, you cannot "splice them" to multiple outputs.

Hope this info helps,

--Noel

That does, thank you!

So with backup pressure or temperature probes, I'd need a totally independent wiring from source to display. And if there's only one CHT tap, then I couldn't wire a splice to the backup.

I'll contact the engine manufacturer for more information about possible backup options for probes.