Transponder

[TommyRust]

Can someone give me a simple explanation on how a transponder works. Do any of ya'll have them installed in your gyros? Hard to install?

[gyropilot]

Tommy,

Try this article... pretty much explains it all:

http://www.public-action.com/911/transpon/

I have a Microair T2000 on my GyroBee:

http://home.usaa.net/~gyropilot/Thun/Avionics.jpg

That's it just below the GPS. My GyroBee has no battery, so the transponder is run off an alternator (through a voltage/rectifier/regulator) only when the engine is running (a Rotax 503).

Microair and Becker are currently the only two manufacturers making a compact lightweight transponders which will fit in a 2.25" instrument hole. But they aren't cheap and they're still long enough that they won't fit in a small instrument pod (this is the reason mine is external to the pod - for now).

Microair's web site is: http://www.microair.com.au/

You can check out one of the two Becker compact transponders at: http://www.becker-avionics.de (http://www.becker-avionics.de/666571_ProductStockCAT.cfm?Group=PTR&SubCategoryID =1&Sub_SubCategoryID=1&Code=CAT) The other is simply a high output power version of the same thing.

It's not overly difficult to install one, but tedious maybe. In addition to the transponder, you'll likely need a "blind encoder" also, which feeds pressure altitude information to the transponder, as well as a stub antenna. Some fancier altimeters have a bind encoder feature built in (particularly digital ones), so that could be used if you have one.

Then you need a data cable to run between the transponder and the blind encoder. You'll have to modify an RS-232 cable yourself to suit, or have one fabricated at an avionics shop. After a trip to Radio Shack and with wiring charts from Microair and the blind encoder manufacturer in hand, I fired up the trusty soldering iron and made my own cable.

You'll also have to connect the blind encoder to your pitot static system (if you have one), that way your altimeter and transponder will agree on the pressure altitude.

Once you install the transponder, you'll have to take your gyro to an avionic shop to have the system tested. This test is required every two-years (per the FAR's) and is noted in the aircraft log book. It only take a few minutes to do once they set everything up. They basically just check to see everything working like it's supposed to (responding to interrogation) and the altitude Mode-C reporting feature of the transponder is reasonably agreeing with what your altimeter says.

Let me know if you have any additional questions and I'd be happy to do my best to answer them.

Regards,

John L.

[joeheli]

Where I can get a voltage/rectifier/regulator system? Do have some picks of the instalation? ;D

[TommyRust]

John, Thanks for the input, I went to a airplane salvage yard and can pick up the whole package for about $400. I think I have enough space in my pannel to mount it. I removed a lowrance from my pannel and I wonder if the power connection from it can be used with the transponder?

[gyropilot]

Tommy:

If you can fit a full-sized transponder in your panel... go for it! Yellow-tagged used ones from a salvage yard are quite reasonably priced compared to new ones.

Jose:

No pictures, but this is the unit I'm using:

http://www.aircraftspruce.com/catalog/elpages/voltregpwrsup.php

Regards,

John L.

[CLS447]

John, I hate to nitpic but,..... Could you please replace those slotted round head screws with either SS phillip head or cap screws?

That is some nice instrumentation & layout. It deserves better hardware. I'm sorta kidding!

[joeheli]

John, thank you !! I am goin to order it . Now the problem is
how to install the unit.

[gyropilot]

CLS447 asked:

"John, I hate to nitpic but,..... Could you please replace those slotted round head screws with either SS phillip head or cap screws?"

I'll get right on it! :)

John L.

[joeheli]

John: Do you have any picture of how you install the alternator?
I have a mac 90 so if you can help me I will be glad. another thing, What other things you have install with the alternater?

Thank you!! ;D

[CLS447]

OK John, that's more like it!

When do we get some full shots of your baby with the new suspension? While you're at it, have someone else take the pic, or use self timer, & you stand next to her.

Are you going to Mentone this year?

[Aussie_Paul]

This was said "John, I hate to nitpic but,..... Could you please replace those slotted round head screws with either SS phillip head or cap screws?"

I will show my ignorance here. Why?

Aussie Paul.

[CLS447]

Paul, all the screws I find in my basement, that belonged to my grandfather, are slotted. Did you ever take apart something that was assembled with slots & slip off a hundred times? I'd go into more depth but I hear the Sopranos Theme song playing.........

Goodnight

[Aussie_Paul]

usually 200 times!!!!! Ok, I get it.

Aussie Paul.

[gyropilot]

Jose asked:

"John: Do you have any picture of how you install the alternator?
I have a mac 90 so if you can help me I will be glad."

Jose,

Can't help you there with your Mac. My Rotax 503 has a little 15amp alternator built right and driven from the non-PTO end of the crankshaft. In my case, all that needed to be done was to rectify the AC output of the built-in alternator to DC power and then regulate it at 12 to 14 volts. No battery is needed with a high quality regulator/rectifier.

Best regards,

John L.

[gyropilot]

CLS447 said:

"When do we get some full shots of your baby with the new suspension? While you're at it, have someone else take the pic, or use self timer, & you stand next to her."

Hopefully this spring/summer when I get some good flying in, someone will be around with a camera (so I can break it). :) I do have a tripod somewhere though.

"Are you going to Mentone this year?"

No chance of that I'm afraid. Too far away and too little vacation time available. However, I would love to try and figure out a way to get down to the Ken Brock Freedom Flyin down at the El Mirage dry lake bed in California this year. It would mean 2 long days of driving each way in addition to the actual fly-in, and I'm a hesitant to trailer my Bee that far on an open trailer (~2500 miles round trip).

Regards,

John L.

[gyropilot]

CLS447 said:

"Paul, all the screws I find in my basement, that belonged to my grandfather, are slotted."

Hey... that's where I got my screws... the basement! :)

John L.

[PW_Plack]

John,

If you should find yourself flying around Scappoose Airport on...oh, say, the second Saturday of some month this summer...Gary Kaminski almost always has his digital camera aimed skyward. (Hint, hint.)

And whataymean, trailer to El Mirage? I thought you had a 10-gallon tank on that baby. Three words for you...

"Long Cross-Country!"

(Or, is that actually two words?)

[ToddP]

John,

I've also been considering El-Mirage this year. Let me know how serious you are. I can probably do it, If I make plans for it now.

[CLS447]

John,

I was just kidding about the screws, sorry. My hourmeter burned up last year so, I sent it back to Westach and they repaired it. I was running the hourmeter and only the hourmeter off of a regulator/rectifier. I now purchased a lower power adapter from Westach which gives the 12 volts for my hourmeter. Their latest version of the tach/hourmeter has this built in.

Anyway, with all this screwing around with the instrument pod, I finally decided to get all the screws and washers all uniform. What a runaround for the screws. This is like the third time changing these screws. I must be nut of some kind. This time I am going to get it right!!

John, where did you run your brown wire from your Rotax harness? Do you get alot of radio interference noise from your engine and if not, why not? I do. Here is the instrument pod, almost done. I think I'm gonna put one of d'em d'ere drift flag thingys on too. Where can I get one real cheap? Maybe Ron knows.
P.S. Come on post some pictures of your machine!

[gyropilot]

Todd P. asked:

"John, I've also been considering El-Mirage this year. Let me know how serious you are. I can probably do it, If I make plans for it now."

Todd,

I think this year I'm going to try to make it, and I'm currently starting to rearrange my limited vacation days to make it happen. I figure I'd need 5 days of vacation in addition to the two weekend days of the fly-in. I think I can do it if I cut back on the number of weekdays I had already set aside for some local airshows (like the EAA Fly-in at Arlington, WA).

I plan to borrow a friends enclosed trailer to carry my Bee for the trip down from Seattle. It's about 1300 miles each way, and with a trailer in tow, it would likely take me two days if driving each way by myself.

There's so many people I want to meet who frequent El Mirage. I regret not making the before Ken Brock left us... I never got a chance to meet him.

Regards,

John L.

[gyropilot]

CLS447 asked:

"John, where did you run your brown wire from your Rotax harness?"

Hmmm... brown wire? What's the brown wire...

I just checked the Rotax 503 installation guide for the dual Ducati electronic ignition type I have, and there's a brown wire which is the ground. I have my engine grounded to both the aircraft frame and to a common grounding point. All electronic devices on my gyro are grounded to this common ground point and don' t use the frame as a primary grounding path (like most automobiles do). Sending electrical current through your aluminum frame held by steel bolts is just begging for corrosion.[/i]

"Do you get alot of radio interference noise from your engine and if not, why not? I do."

I get very little ignition noise on my radio and if I had to guess (and it's only a guess), I'd attribute that to the fact that my antenna is about as far from the engine as possible (up in front of the instrument pod) and I use resistor spark plugs and resistor spark plug caps (all stock Rotax parts) in the ignition system.

I do use the ANL (automatic noise limiter) function on my Icom A22 radio because otherwise there's enough background noise when the radio breaks squelch to be mildly annoying. With the ANL on, the background is quiet and I can normally hear radio transmissions clearly.

Hope that helps,

John L.

[gyropilot]

Paul Plack said:

"If you should find yourself flying around Scapoose Airport on...oh, say, the second Saturday of some month this summer...Gary Kaminski almost always has his digital camera aimed skyward. (Hint, hint.)"

Paul,

This *is* the year I'm coming down! Probably looking at May because I'll be down in Shoshone, California (near Death Valley) on vacation during your April meeting. I'm thinking about bringing my gyro down with me on vacation so I can log some desert x-country flying around the California / Nevada border between Shoshone, CA and Pahrump, NV. I was also thinking how cool (well hot actually) it would be to fly into the Furnace Creek airport in Death Valley National Park... -200 foot field elevation! It's about 50 miles from the Shoshone airstrip.

"And whataymean, trailer to El Mirage? I thought you had a 10-gallon tank on that baby."

Well Paul, I was going to, but I just haven't figured out where on my gyro to carry all the gallons of 2-stroke oil that would take! :)

Later,

John L.

[PW_Plack]

John, Todd...

You guys keep me posted. I won't be in a position to fly this summer, but I'd love to share part of the ride down. I also have a nice truck with a hitch if it helps. As Todd knows, I'm a sucker for a road trip...

[Caribean_gyro]

AS for the screw I recomend Brass. Aircraft spruce has them with anodizing black color. see below GPS goes on the left side

[joeheli]

Hey Chuck! What happend with your Twin star, did you
have a "Gyro jacking"? ;D That panel is empty!! That is not the way I saw it last time . You have about 100 stuf
on your panel. ;D

[CLS447]

After like 3 hours today, I now have all the instrument mounting screws all the same!!!!! All 6-32 ss phillip heads! My tach & left CHT/EGT were threaded for #4's. I must be crazy! What a bitch to try to drill & tap those little brass rivits that hold the gauge together! They just spin & spin. Dremel tool to the rescue!! Always save these little projects for some other time...Like NEVER!!

Anyway that's done. This is my pod for my 447. Oh no! I forgot the post for my yaw string. Maybe tomorrow?

[CLS447]

John, thanks for the info. I think I only used the brown wire to ground the Reg/Rec. I will now try grounding it to the frame as you have. With my 447 upside down I am reluctant to use the Resistor caps & plugs.

I get so much engine noise to my CB or Icom A-20 that they are unuseable for me. Shut off engine, & they work fine! Very frustrating! Over $1000 in helmet & radios & it's just been easier to fly without.

Hopefully my Subaru will not interfere. I will be trying that real soon.