Mode C retro fit

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mb2
Posts: 25
Joined: Fri Feb 06, 2009 12:44 pm

Mode C retro fit

Post by mb2 » Sun May 24, 2009 3:26 pm

I require some help to fit a Mode C module to an existing transponder. The mode C unit is the correct one for the transponder but looking at the instructions, it does not seem plug and play.

Ideally a contact of someone that would visit the strip (Midlands) and either assist or undertake the job would be good. (Obviously appropriate reimbursement included).

Please send a PM if interested or know of someone I could ask.

Thanks
027411

Rob Swain
Posts: 393
Joined: Tue Jan 08, 2008 2:11 pm

Post by Rob Swain » Thu May 28, 2009 4:24 pm

Let me guess - a Narco AT50, by any chance?

I've come across a couple of these that are mode A only, even though they are identical looking to mode C.

How do I know? My old plane had one that we got cheap because the previous owners couldn't get it to work with an encoding altimeter. We used it mode A only. OK this isn't conclusive, but...

Current aircraft has a mode C AT50. Worked OK until it was reporting a code other than what we set - still giving altitude though.
Put another, visually identical, AT50 in the tray. Perfect code, no altitude. Fixed original (good stuff, contact cleaner) and replaced it - correct code and altitude again!

Good luck!
Rob Swain
If the good Lord had intended man to fly, He would have given him more money.

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