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Hi there,

I'm just about to start flight school and i've purchased a headset. I found a deal that was too good to pass up on Ebay and grabbed a David Clark One-X however it's the XM model with a U174 plug.

A quick search online brought up a list of U174 (US NATO) to twin-GA adapters so I assumed this would be fine, however having made a few calls this morning it sounds as though it's not quite that straight forward.

I think at the very least I need a low impedance to high impedance converter, but my question is has anybody else had to deal with this before? Specifically with David Clark? And do you know if I can use any old low to high impedance or does it have to be David Clarks own brand? The majority just seem to be sold from the States and struggling to find the right one stocked in the UK?

Any help or advice would be appreciated by a newbie to the aviation world just looking to get set up before day one.
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By Paul_Sengupta
FLYER Club Member  FLYER Club Member
As well as impedance, you have to know if the microphone is amplified or unamplified. If the latter, you'll need to add an amplifier.

Depending on exactly what you need and are trying to match there are things available here.
Thanks for taking the time to reply Paul, it's appreciated.

The headset I have in question is ... -c-17.html I'm not sure if it was an amplified or unamplified mic i'm afraid. Wonder if you might know?

Thanks for the link. I had actually already spoken with FlightStore about this device but they couldn't confirm if it'd definitely work as I think the adapters unfortunately aren't 'catch alls' and some headsets have certain nuances that would make them incompatible i.e. different mics or Ohm ratings for example. But I feel at a loss as i'm struggling to find a solid answer and the only way i'll know for sure is once I plug in to the aircraft in Poland!

David Clark customer service did advise me of an adapter they supply and said it'd work but it seems this is only for sale in USA, so i'm wondering whether the likes of the one you shared might do the same job? Their one is - ... -40880g-01

Headset just arrived and I love it, so i'm really hoping I can find a way to make this work!
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By Paul_Sengupta
FLYER Club Member  FLYER Club Member
Jallen wrote:The headset I have in question is ... -c-17.html I'm not sure if it was an amplified or unamplified mic i'm afraid. Wonder if you might know?

Sounds like US military which *I think* would be 5 ohm unamplified, but I can't be sure. Given that it is US military, a US military to twin plug adaptor box as I linked above would probably work but like the shop, I can't say for certain.

Can you take your headset to one of the shops to try it, perhaps in conjunction with a civilian intercom?

This seems to be a good price but none in stock!

Make sure you get the correct one, there's US and UK version of the PA89, if your headset has the U174 plug then you want the US version.
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By Dodo
FLYER Club Member  FLYER Club Member
In the end it might just be easier to sell it, and buy a headset that will work without adapters or battery powered amplifiers.

I did once own a share in an Enstrom helicopter that needed 2 different adaptors to connect the headset I had bought whilst training in a Robinson 22 to the radio, and another adapter to connect the passenger headset (which was my aeroplane one) to the p2 socket.

It was a pain in the proverbial and occasionally led to r/t issues.
Ian Melville liked this
Hi Paul_Sengupta and DoDo, sorry for the delayed reply. Busy time moving homes (and countries) and starting flight school.

I finally got a chance to test the headset with adapter (thanks Paul for the suggestion. I ordered the same one as you posted but from another website) and all seemed great, ATIS and CTR coming through loud and clear...and then the trouble came when I tried to 'radio check" CTR and got no response. I also tried talking to my instructor and he couldn't hear me.

Before I go through the rigmarole :shock: :shock: :shock: of carting this thing back to the UK and trying to find a buyer I wondered if you had any last suggestions as it feels like I am almost there but just missing the final piece? For instance, and it's only just dawned on me but would switching from mono to stereo maybe affect the mic?

It's a lot of effort to return the adapter, sell the headset and buy a new one so before doing so (and because I love this headset) I just wonder if there's something I can do to tweak the mic to get it to work in GA? The adapter btw DoDo is not battery powered so that's at least one less thing to worry about,