Lagentium

Evening all, we have a problem with our ADF in our aircraft, it just doesn't work properly! The Ident is being received as we can hear it and the needle does point but its nowhere like where it should be. The test mode where the needle should point at the wingtip also doesn't work. I was wondering if anyone has had any problems and can give me any advice. Also Avionics Engineers seem to be like rocking horse s@@@e here in Yorkshire, if anyone can recommend one to come and inspect our aircraft that would be brilliant.

Thanks in advance, Jim

Big Pistons Forever

The first thing you should do to any balky radio is get an avionics hex screw driver and loosen the hold in screw. Gently pull the radio out of its rack and then slowly but firmly push it back in and tighten the screw. Re-racking radios will often fix a poor contact on one of the connectors at the back of the radio rack.

However personally I think a failed ADF is God's way of telling you to get a GPS

percy prentice

as BPF but also check the earthing on antenna

Lagentium

Thanks for the replies gents, I use the Skydemon GPS, the ADF is for the IMC rating that I'm doing, as you all know I need the bloody thing to be functioning, otherwise I will have to use a club plane, which defeats the point of owning a quarter of one!! Also the face that the wife pulled when I told her about using a club plane scared the bejesus out of me. Please help as I don't want to see that angry face again!

Cheers, Jim

Mariner9

Why not fly the aircraft to an engineer rather than pay to get him/her to you?

RGV in Gloucester are excellent with avionics. (Suggest you dont fly the NDB approach at Gloucester on the way )

Edited to add vital in my view to get it looked at by someone who knows what they are doing if you are going to use it in IMC.

Big Pistons Forever

After re-racking the next easy step in troubleshooting is to see if you can borrow another unit and swap them out, then you can determine if it is the ADF itself or the wiring/antennae. If it is the ADF then you can ship it to any radio shop and get them to repair it.

What is the make/model of the ADF ?

wigglyamp

Probably the nearest avionics engineer to you will be Richard Wilkinson of Multigflight in Leeds.

Lagentium

Cheers Wigglyamp, I have had dealing with Richard in the past, he sorted out a filter capacitor for our alternator and seemed a nice bloke. Maybe I should get on the phone tomorrow and get him to come down to Sherburn.

Cheers, Jim

A and C

The first thing I would look at is the look at is the loop antenna.

Tell us what type of ADF it is

Big Pistons, a GPS won't pick up the Cricket scores.

Lagentium

Thanks everyone, the ADF is a Bendix King KR-87

Johnm

Pretty reliable box so if the connector reseat doesn't work I'd suspect corrosion issues around the antenna

Lagentium

Right, I have a plan of action then. Without sounding like an absolute moron, are the aerials easy to check for corrosion? Is it as easy as whipping the cover off, considering its fitted externally on the belly of the aircraft, or do they have special fixings? The only bright thing about having problems is that I'm starting to understand how things work properly.

Cheers, Jim

turbroprop

Hi Lagentium.

I assume your aircraft is on a permit to fly and not a C OF A. Poking about on an aircraft issued with a C of A can lead to all sorts of problems. The sort of work you are talking about is outside the scope allowed by a pilot owner.

Dan Winterland

Donate it to a museum and buy a GPS!

Flyingmac

Have a word with Les Scattergood at Sherburn if he's still about.
Failing that, Graham Fox at Bagby uses a very good travelling Avionics Engineer. Give him a ring for John's number.

Lagentium

Dan read the thread from the beginning old love, having had a decent think about it Flyingmac I wasn't confident about re racking the ADF and didn't think too long about doing it until I realised it would be a daft thing to do, is there anything stopping me just taking the lid off the loop antenna to check for corrosion? We take the engine cowling off regularly to preflight it so wouldn't have thought it would be much different to that. Les has known about the problem for ages but hasn't done anything, he told us it needed degaussing so sent me on a wild goose chase to find a company that could do the work, they came and checked it out with a magnetometer and it didn't need it. Richard Wilkinson from Multiflight is hopefully going to make a visit to try and cure it.

Cheers all, Jim

goodmand1

This company should be quite close to you?

aircraft instruments ltd

Winhern

"The test mode where the needle should point at the wingtip also doesn't work"

Surely the test mode uses internally generated signals, which implies the fault is not with the aerials, and probably not with the connectors?

A and C

This unit is not usually subject to the connector corrosion problems of the KR85 as the loop antena connector was moved to a position were moisture was unlikely to collect.

My thoughts are that the most likely problem is with the loop antena it's self but I will ask a few more questions of the real radio experts hat I know.

It should be understood that with this model of ADF the loop & sense antena is a combined unit.