it seems to be possible to have one main frequency while listening to a second frequency
this seems to be pretty much standard nowadays, the newer Garmin kit (GTN, GNC) does that too…
Have a look at the Bendix King KT74 as well. It’s made by Trig (well, the back end is at least), but the user interface is miles better than the Trig. It’s got 8 proper buttons instead of the single twiddle and push of the Trig. Similar price.
Ok, I get it for the radio. I’m thinking of going for a Trig radio as it seems to be possible to have one main frequency while listening to a second frequency at the same time (useful for ATIS)
I agree with Bosco. Range increases with the square root of the output power, so doubling the output power will only give you 40% more range. I doubt you’ll notice that. Furthermore, range is sometimes limited by the earth curvature, and no amount of output power is going to help there.
I wouldn’t spend any money to get a higher wattage on the radio.
Trig TT31 has been great for me
TT-31 is a good choice, it is ADS-B ready, operates reliable and support from Trig is excellent. You might want to hang around for a replacement Trig radio as well.
I went to my radio tech and he tested the transponder. It did not take him too long to find the problem : The transponder, installed in 1977 is now old and does not deliver more than 70W instead of over 200W as it’s supposed to.
Also, the external antenna was a bit rusty and we had to replace it anyway.
He sent me a quote to have that AT150 replaced by a Trig TT31, it sounds quite good, does anyone know this transponder and had any good/bad experience with it ?
I am also thinking of replacing the radio at the same time, but I was thinking about upgrading to a 10W radio instead of my current 5W, but apparently above 6W, it’s expensive and harder to get !
This Dittel KTX2 seems to be ok, however it’s really small. Is it not difficult during the flight, to change transponder code with those buttons ?
I have never used a Dittel before, I have no idea if it is a good unit, but I have used other 2 1/2" transponders and it’s no problem dialing with a rotary knob, essentially the same as a radio. A “flat” Garmin is easier/faster though, but will be impossible to fit in the panel of my Onex.
Homebuilts and microlights can, I believe, install a Mode C unit.
No. Probably different from country to country, but in Norway mode S will be mandatory at some unspecified time. It’s not at the moment. 8.33 kHz will be mandatory from 2018. Microlights and homebuilts have to follow the specs regarding avionics. I thought radios and transponders also had to be certified, but just received information that they don’t. Looks like all mode S transponders are certified anyway.
Make sure they also check the coax cable. Most of transponder related problems I have found during avionics testing are due to poor coax cable / connectors. If it is equiped with a monopole antenna instead of a vin make sure the antenna is still intact. They sometimes break.
This part must work ok with a new installation as well. Your avionics shop will be able to measure the antenna installation as well.
