Primarily for general aviation discussion, but other aviation topics are also welcome.
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By rohmer
My next step to attack the remaining noise (rev related ticking and the screeching from my Avmap Ultra AH) is to rewire my headset jack looms with screened cable.
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By rf3flyer
@rohmer you write about noise, rev ticking and navaid screeching, but do you also get engine noise through the mic?

My aircraft has no electrics, intercomm or complex navaids and with my 550L I have had readability 5 but also readability as low as 3 due to engine noise, which I can hear in the side tone. My previous radio had no side tone so cannot compare. Others at my home field have variously commented that my transmissions are quite noisy (engine noise not electrical interference) but clearly comprehensible, or that mine are better than others. The ANL feature in the 550 appears to help a very little and I wonder if you have found any other menu settings that might improve this.

I have also considered that the mic on my headset may not be compatible. Any thoughts or insights you'd care to share?
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By rohmer
rf3, my engine related noise is not external noise picked up by my mic but electronic interference which I can squelch out but which takes more & more squelch as the revs go up and thereby I lose reception sensitivity. I didn't experience this with my previous radio, intercom and headset jack set up which was installed inbetween my seats and hence, was well away from other wiring behind my panel. I can still transmit & receive 5x5 from 20nm at 2000ft but the volume on the 550 has to be set at max and it's noisy. The sidetone and ANL settings make no difference. If you have a mic related issue, maybe trying a different headset would be an option? It's not something I've tried.

Before I started my rewiring, I asked Sigtronics for their advice on wire type & gauge for my looms and they recommended 22 awg and said screened cable was unnecessary. I'm now not sure that was good advice. I've since spoken to Doug Law at SteinAir who recommended I replace the headset and ptt cables with screened ones. Additionally, the Yaesu SCU-15 headset adapter has the 2 braids to the inline jacks acting as a ground wires. In wiring these into my Sigtronics intercom I pigtailed these braids together into one earth lead. Harry Mendelssohn suggested that this might have lost the screening protection so it's another potential gotcha to correct. The Sigtronics wiring mod for the 550 includes a 220 ohm resistor inserted into the blue headphone audio circuit and if the headset adapter loom needs screening, it might need to add a braid over this resistor to maintain the continuity of the screening. l'll report back.
By Spooky
If I wanted to use a Yaesu transceiver (probably FTA450L) with a Lynx avionics interface (currently working with an Icom A3), is it as simple as buying a CT44 to Yaesu 4 pin adapter?

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By segillum
I've just noticed that v3.00 firmware for the FTA-750 is available at the web site. However there's no changelog and the downloadable manual still refers to v2.06. I updated my FTA-750 without any problems but can't see any difference in features or functionality and nothing comes up via Google.
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By znww5
The only thing I have noticed with the v3 software on my FTA-550 is that the behaviour of the battery icon has changed. Previously, once the battery had been fully charged the battery icon would drop back by one 'notch' after a few minutes use - that now no longer happens and it now behaves as one would expect. Maybe they changed the software set points for the Li battery - otherwise I can see no difference.
By Donald NZ
Re the radio noise increasing with revs , following
all at your own risk and in conjunction with your lame.

If it was ok with an existing radio and only started once you swapped radios I'd start with the radio install.
I'd do the following one at a time to see what fixes it. Electrical noise can be a challenge to find.

I'd run the radio on a gel cell and see it the noise is still there, this might indicate it's getting in the dc / power supply to the radio.

if noise goes away

I'd try making sure all my grounds at the radio are connected at the same clean metal point not on the aircraft frame ; radio, aerial, dc supply and headset and ptt if practical.
if you cant help that it is connected to the frame then so be it.

Then I'd make sure the above radio ground point is connected to the engine frame at the same location as all the other grounds from all the other equipment.

So to write it out in a 2 d wiring diagram of the aircraft electrical grounds it would look like a star with a central point with all circuits and sub circuits going to that point.
This might help reduce ground loops or potential voltage differences, frame & engine electrolytic corrosion.

I'd then check the positive power supply to the radio was not wired to the same source as the ignition system

I'd make sure my ignition system, starter earth / negative lead and engine grounds are to that same point.

if the noise was still there when running on the gel cell

I'd check my spark plug leads with an ohm meter then swap out my spark plugs.
I'd put suppressors on the ignition system primary then secondary.
I'd shield and ground the ignition secondary as best I could [fine chicken wire mesh over the outside of the ignition coils hollow braided over the spark plugs and leads all grounded to one point. [some older Bmw cop bikes had metal shields over the coils to allow better radio reception.}


fta 550 aa for about a year now , yet to use it for real , a big hand held but way easier to read in a hurry.

Kind regards Donald
By Andrew
Thank you for your reply. I tried to select a VOR or ILS frequency but it didn't work. All i want to do is to check if this functions are working. I am quite far away from any airports and I can hardly pick any signals. Few days ago I was within metres of a VOR station, I was using NAV I set up the frequency and the GPS coordinates and it didn't work. (Now I know it wasn't supposed to work) All I could hear was the Morse code for the VOR station. But the display didn't show any details for VOR or ILS. What do you suggest? I am afraid that my radio doesn't have this function.
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By neilmurg
I just tried my 750 at Ockham on the ground. I selected freq. and the display changed to a VOR the unit played the morse. The display didn't go to VOR of I chose a frequency it wasn't receiving, eg MID
You need to get within range. That's the first time I've tried it successfully, it doesn't work at home. Now, GPS....
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By Grumpy One
For the Yaesu FTA 750L ......Yes... Simply dial up the required navaid frequency.
If the chosen navaid is in range, the screen will automatically change to the navaid screen, VOR or ILS, whichever is appropriate.
I found the accuracy to be spot on especially the ILS, both in the localiser sense and with the glide slope. A really good back up. Very happy with it :D
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By bambuko
Can any of you guys, please suggest suitable boom mike for use with Yaesu radio in my glider. I have wired PTT as per advice in this thread, modified Yaesu SCU-15 to continue using internal speaker, and connected an old electret mike (used before succesfully with Delcom and Icom) and everything works fine apart from the mike - it transmit very quiet and crackly.
When I tried to buy new mike they all seem to be wrong impedance ...
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