Icom A-6
 

We have an Icom A-3E mounted in the L4 Cub,running of a small rechargable external battery and external aerial and connected to internal comms.
Now some of the radio buttons are u/s and it is a faff changing frequencies.
The new A-6 replaces it and has a toggle function between most used frequencies,plus auto button for the emergency frequency and other upgrades.
Has anyone used this new A-6 in mounted in an aircraft?
Or even comments regarding it's use as a handheld?

Lister:)

I believe it's become quite popular in microlights and you might get some wisdom by asking on the BMAA Yahoogroup, or at your local microlight club (unless you get some useful advice here of course, which one usually does).

G

Genghis,I will wait patiently on here.;)
Lister

I have the IC-A24 (same as the A6 but with VOR capability). Use it as backup/emergency unit. So far never had to use it in anger in-flight, but very happy with it all round. I don't think the price difference is huge, so if you intend to get one, perhaps go for the A24 with the added Nav function.

You can download the manual from the ICOM site and have a closer look.

It means that CAA shut down their radio approvals section without checking that EASA had one. So, for the moment, there's nobody who can approve handheld radios. It would hardly be fair to expect Icom to wait five years for CAA to solve this!

G

I had an A6 as a backup during a period of radio uncertainty. It was fine. Worked great with the headset adapter. I've heard stories of people experiencing issues with them, but can only surmise it's user error.

A log of A/G guys use them during the summer when they want to get out of the greenhouse, err, tower.

Headset problems with ICOM A24
 

I purchased my A24 in 2005 at the Oshkosh EAA fly in. I have had it 'ON' nearly continuously mounted in my pickup with the DC power cord and an external antenna. I transfer it into my flight bag when flying, and back to the truck when on the ground....recently, my #2 NavCom died in my aircraft, so I wanted to use the A24 until I could replace the panel mount. Tried it with a PTT from Sporty’s and my head set. Growls on transmit.

I also tried my other external PTT and two additional head sets (all three headsets tried are different brands). All three headsets and both PTTs work in the aircraft with the panel mounted #1 NARCO radio. But all combinations Growled with the A-24 / OPC-499 / remote PTTs/ 3 headsets.

Last night I spent several hours with my former boss and Ham radio operator, at his work bench…(he has better test equipment than my shack, and was an avionics tech while on active duty)

It seems to be an impedance issue in the mic circuit.
- Radio with out any external attachments checked out fine (frequency count and stability good, power and modulation as expected using HP freq counter/ modulation check / spectrum analyzer)
- Plugged in the OPC-499 head set adapter. No head set… expected nothing but carrier… but had modulation<?>… I was keying with the PTT in the body of the radio… Added the EXTERNAL PTT switch (still no head set). When using the external PTT (no head set) I got the pure carrier I expected. Apparently, even though the OPC-499 was plugged in, it does not disable the internal mic from the internal PTT.<?>

Now add the headset… GROWL!!!!!!!!! Some type of feedback/ oscillation!!!

Removed the rubber duck antenna and replaced with 50 Ohm BNC termination plug… (I.e. eliminate the RF feed back.) Still GROWLssss!!!!!!

Showed ~10v open on mic circuit, and loaded with mic from head set pulled down to ~4.4Volts.

Placed variable resister across the mic … I could pull down the circuit until I stopped the oscillation, but that also pulled down the audio drive to where the modulation was very low.

Went online and looked at schematics of some ICOM 2 meter units… I saw biasing circuits with a dropping resister and by-pass capacitor in some of their tone encoding mics…..

-----------------------------------
I also re-read the manual …. On the head phone circuit it specified 8 olms<?> great for Hi-Fi… but not 600 olms of aviation head sets….

Hey ICOM… how about an adapter that works with a broad class of aviation headsets… not just Dave Clarks…. As suggested in the manual….

I’d sure like a fix for this!!!

Thanks
Walt.
Ret. Military Communication Officer
Ham Radio Operator
Private Pilot.

P.s. The DC power cord plug in the lower right side is a weak point… I have to use rubber-bands/wire ties/Velcro to keep the plug in reliably.

Dont forget the Vertex range I think its the 220 thats supposed to be very good,

Some good deals for them on ebay.

Nick.