Hand held radio.

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Trevor Harvey
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Location: Scotland

Re: Hand held radio.

Post by Trevor Harvey » Mon May 01, 2017 8:31 pm

dmcnicholl wrote:
Trevor Harvey wrote:I got Harry Mendellson to chop the plug off the Yaesu headset adaptor and splice it onto a two place intercom, which has a PTT socket.
Well this is the LAA so homebuilding is allowed. :wink:
Chopping the plug off the Yaesu lead was an option but I wanted to keep that as a plan B if I cocked it up. Also, mine is a single seater so I have no intercomm, and cockpit space is tight so a custom solution seemed the way to go.
Is it all fixed? cos any 4 pole 3.5mm plug would do, except it won't have the screws that the Yaesu one has.
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dmcnicholl
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Re: Hand held radio.

Post by dmcnicholl » Mon May 01, 2017 9:18 pm

Trevor Harvey wrote: Is it all fixed? cos any 4 pole 3.5mm plug would do, except it won't have the screws that the Yaesu one has.
Is it all fixed? I can't yet say. It works on the ground, readabilty 5 both out and in, but I have not yet had the chance to test it mounted in the aircraft with the engine running.

Any 4 pole 3.5mm jack won't do because the shoulder on the ground pole is too large in diameter to insert into the Yaesu case socket. There appear to be iPhone repair jacks that might fit but I cannot confirm that they will. My solution was to turn the shoulder down on the lathe. That means the shroud cannot be used and the terminals have to be 'potted'. My prototype is a little 'free form', but it works.

No screws, for sure, but the connection is positive though I have it in mind to do it again and I think it possible to use the Yaesu socket cover as a base, which would then let me use its screws.

[edited to add]
Another option, and possibly the easiest, is to take the standard Yaesu headset adaptor, the SCU-15 and cut the microphone lead for breakout to a remote PTT. There would be no need to cut the speaker cable. (Cut it at the mid point to leave about 3" of cable on either end to work with.)
It might even be possible to not cut the cable at all but just open it to reach the screen and the PTT conductor from which to breakout the PTT.
Donald McNicholl
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Trevor Harvey
Posts: 190
Joined: Mon Feb 04, 2008 1:20 pm
Location: Scotland

Re: Hand held radio.

Post by Trevor Harvey » Tue May 02, 2017 12:16 pm

I don't understand the incompatibility with a standard 3.5 jack.
The aircraft and Yaesu plug are 20 miles away, but I connected a 3.5 socket into a DC headset to use the mobile phone through the headset and plugging in the cable to that and the radio I'm receiving ok but it screams if I press TX. Though the plug seems to fit ok.
I haven't tried the phone/headset in the aircraft yet but it works in the house.
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dmcnicholl
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Re: Hand held radio.

Post by dmcnicholl » Tue May 02, 2017 5:10 pm

Trevor, I cannot help you. Mobile phone through the headset? Sorry, way beyond my comprehension. I have no smart phone of any flavour.

Perhaps the plug you are using is similar to the iPhone repair jack I mentioned before, and I called it a repair jack simply because that's how I had seen it described on ebay.
Donald McNicholl
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Trevor Harvey
Posts: 190
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Location: Scotland

Re: Hand held radio.

Post by Trevor Harvey » Tue May 02, 2017 6:39 pm

The jury is still out as to whether it will work whilst also plugged in to the radio.
I had to add a second ground wire to the mic to make it work, whether that has screwed things up with the radio I don't yet know. I'm on the edge of my comfort zone with it too, being a complete electronicphobe. I would be happier with half inch cap screws and a mic made by Moore & Wright. :D
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Rob Swain
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Re: Hand held radio.

Post by Rob Swain » Wed May 03, 2017 3:29 pm

dmcnicholl wrote:Well this is the LAA so homebuilding is allowed. :wink:
It's a hand-held so it's allowed in a certified aircraft as carry-on equipment!

8.33khz spacing is nothing to do with poor performance.
If your display is showing the 'normal' 25khz spaced frequency then it is operating in normal 25khz mode.

A carp power supply could be a cause of carp performance - run the hand-held on fresh, decent-quality batteries (or a full re-charge) and compare the results.

Comparing a hand-held using a rubber duck to an installed radio using an installed antenna with a decent ground plane is like comparing a kid's toy radio to the BBC's DAB services. At least plug the hand-held into a decent installed antenna.

Power output on an installed radio is probably somewhere between 6 and 15 watts, and that will be a reliable figure as it is part of the certification of the equipment.
The Yaesu 750 is listed as 5 watts, and being non-certified I would take that as being 5 watts on a good day, with the planets in alignment and not having a 'Friday afternoon' example!
There's an element of you get what you pay for in all this!

As regards connecting a phone into the aircraft headset: I fly the plane to get away from the bl**dy phone!
Rob Swain
If the good Lord had intended man to fly, He would have given him more money.

Trevor Harvey
Posts: 190
Joined: Mon Feb 04, 2008 1:20 pm
Location: Scotland

Re: Hand held radio.

Post by Trevor Harvey » Wed May 03, 2017 5:45 pm

Bearing in mind that we skinflint LAA types are well aware of the limitations of handhelds, and the fact that the cost of an unnecessary replacement installed unit is about half the value of some of our aircraft, we will get round the stupid regulators as best we can. That is why the previously mentioned dipole arrangement interests me.
As for the phone, you are lucky to be able to escape the thing, I wish I could, mine is a domestic emergency necessity.
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Trevor Harvey
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Location: Scotland

Re: Hand held radio.

Post by Trevor Harvey » Sun May 07, 2017 12:34 pm

Question, is there anything special about the RG 58 co-ax cable mentioned?
It seems to be readily available and quite common.
I note that the co-ax to my aerial is a bit iffy looking.
Along with the thin braided wire ground plane I think this may be part of my problem.
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John Dean
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Re: Hand held radio.

Post by John Dean » Sun May 07, 2017 10:53 pm

There is nothing special about RG58 but you would be much better of with the higher quality RG400.

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John Clarke
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Re: Hand held radio.

Post by John Clarke » Sun May 07, 2017 11:23 pm

I've finally managed to fit my FTA-750 and so far all is well. The audio quality, both on transmit and receive, is much better than my old Icom IC22E but I haven't yet been able to test it with a station 20 miles away at 2000 feet as required. One thing that's very noticeable is that the Yaesu is much less susceptible to ignition system interference.

Be careful with the MOD7 form for the new radio. An email about this was sent to LAA inspectors a couple of days ago as so many forms have had to be rejected. Having seen the email I think it would be a good idea if the LAA made the information in it available to all members.
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dmcnicholl
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Re: Hand held radio.

Post by dmcnicholl » Mon May 08, 2017 8:03 pm

Be careful with the MOD7 form for the new radio.
Why would you need a form for this? It's a handheld radio, not an installed radio. You may have clipped it onto something so you don't have to hold it in your hand, and you may have plugged in a headset but it's still a handheld radio. Even the CAA in their 833 cost offset scheme acknowledge and allow for this and the required radio licence is different too.
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John Clarke
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Re: Hand held radio.

Post by John Clarke » Mon May 08, 2017 11:02 pm

The MoD7 form specifically states "it is required to list in the table below all currently installed transmitting avionics equipment fitted to the aircraft, e.g. comm radios, transponders..." and there is also a section covering hand-held radios:- "For equipment with a CAA ‘LA3’ approval number, a placard must be fitted adjacent stating ‘Not to be used in notified airspace’."

I'm not using it as a hand-held radio. It's installed in the aircraft, using aircraft power and connected to an external antenna so I assume I need to complete the form as it's not a temporary installation. Happy too be proved wrong but how else do I get my radio licence changed? I can see that if you can take the radio home every night then the MOD7 wouldn't be needed.
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dmcnicholl
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Re: Hand held radio.

Post by dmcnicholl » Tue May 09, 2017 7:24 am

..." and there is also a section covering hand-held radios:- "For equipment with a CAA ‘LA3’ approval number, a placard must be fitted adjacent stating ‘Not to be used in notified airspace’."
What a load of bull! Next they'll require a placard beside the PTT stating "Press to transmit". Supposing you carried your 750 clipped to your harness, where on earth would it be appropriate to put the placard? The people who write these forms need to get a grip.
I'm not using it as a hand-held radio. It's installed in the aircraft, using aircraft power and connected to an external antenna so I assume I need to complete the form as it's not a temporary installation.
I'd argue that despite being fitted to some bracket in your cockpit with an external power supply and antenna it is not 'installed' in the sense that installed avionics are 'installed' but is merely secured for crew safety. Otherwise you might need a placard stating 'Loose radios are a potential hazard to cockpit occupants in turbulent air or during aerobatics (if so approved)'. That you don't have to take it home every evening to charge the battery is neither here nor there.

My 550 gets 'installed' into the cockpit for flight too but that doesn't change its status as a handheld, transportable radio and I don't believe the LAA have either the technical ability or the regulatory authority to change the device's status from 'Transportable' to 'Installed'.

Lastly, if there was an issue with an inspector over this my short term solution would be to remove the radio before the inspector got there and refit after he'd gone. The longer term solution would be to get another inspector with a better sense of proportion.
Donald McNicholl
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Trevor Harvey
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Location: Scotland

Re: Hand held radio.

Post by Trevor Harvey » Tue May 09, 2017 10:13 am

I would agree with above. The rules get well enough gold plated as it is, why encrust them with diamonds just to make sure?
As far as I remember, a hand held radio is allowed regardless of its flavour, though I get told by others that only the Icom variety is approved. Could that be clarified?
If true then why are we talking openly about the Yaesu?
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dmcnicholl
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Re: Hand held radio.

Post by dmcnicholl » Tue May 09, 2017 10:28 am

Both Icom and Yaesu handhelds fall under the CAA 'LA3' approval.
See here: http://www.caa.co.uk/General-aviation/A ... Hz-radios/ under 'LA3 approved equipment'.
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