Thorp Air Command - T18.net

I was having trouble with terminal controllers reading mode C so I pulled the transponder and encoder (ACK A-30) and shopped around for a price to see whats wrong...

the local avionics shop quoted $90 to look and a minimum of $90 x 2 if they had to do anything other than look) $270 + parts plus more labour so I continued to shop.

I found a fellow (recommended to me by friends at the Springfield Flying Club) that works in a shop for a small commuter Co. said he would give me a free estimate; sounded like a good deal.

He called and told me that mode C does work, problem is with the transponder on the receive side not the encoder; it can't hear an interrogation from more than about 10 miles so it won't respond (mode A works fine ?).

He estimates 4 or 5 hours at $80/hr plus parts to repair..

What now?

Looks to me like a $500 - ? bill to repair the Collins. I plan a panel upgrade in a few years (not now ) and would like to get a transponder with mode C (mandatory in most of my area) and am torn, do I leave it and stay out of terminal areas for a few years or throw money at the Collins to fix it, or replace it?

Ebay may be your friend. I am not an advocate, I'll just tell you my experience. I have bought two Cessna/RT-859 transponders on ebay at around $400 each. Both worked well, then one developed a symptom of alternately broadcasting 7700/1200. Took it to my favorite shop in Sacramento, after 30 minutes of testing, fixed loose ground connection on the PCB for $20.
Ebay has been my friend: two Narco Com 810s (~$500ea) and two Narco AR-850 encoders $25/$35. All have performed well. YMMV. Oh, and my color moving map GPS.
Let the chorus begin, because I am sure there are those with the opposite opinion of Ebay.
Terry
N51079
KSCK

_________________
[b]Terry[/b]

I've had good luck with all the Ebay items I have bought. My albatross was Barnstormers. All five deals were bad but a salvage yard in California made good on the Narco transponder and a private seller in Seattle on the auto pilot that cost over $100.00 to ship back.

When my old kt76 bit the dust I went to EBay, I bought one from Wentworth, in Minneapolis, I won the bid for 275.00, they guarenteed it. I had it in 2 days, put it in and it was giving wierd varying replies to ATC. Wentworth said send it back, they have ther own "in house" tech. They sent me another 2 days later, it was spot on and has worked flawlessly for over a year.

One more thing the garmin 320 is a all electronic, I missed a couple on Ebay in the 700.00 range, most of the guys in the RV group I hang with have this model and swear by it. Also there is a guy in Florida that has fixed prices for Transponder repair, I found him by googling "aviation Transponder troublshooting", his site had a complete how to do basic troublshooting.

Thanks for the great ideas, I am going to try and get a FIRM price from this fellow so I can make a decision. I appreciate the feedback about prices and options, otherwise I have nothing but new retail to go by....

I should know more Monday-Tuesday

I think I found it...is this it?

http://transponderrepair.com/

yes Tim that is the guy, I didnt use him because Wentworth had such a good price and face plate was in new condition.