131.375Mhz

[cscotthendry]

It seems like there are still a lot of pilots who don't know about this, so I'm posting this to raise the profile a bit. On the Sunshine Coast of Queensland there is a radio repeater that records your transmission and plays it back on the same frequency so that you can hear it and check your readability.

 

All you have to do is dial up 131.37(5) on your aircraft's radio, make a call, the let go of the PTT and wait for the playback. What you hear will be pretty much how others are hearing you.

 

Obviously, the further away you are from the Sunshine coast, the more the signal will be degraded by distance, but at least you'll get an idea of what you sound like.

 

Oh, and tell everyone you know in the area, to try it. Anyone can use it, even airliners.

 

 

[JimG]

Thanks a lot to Mark Kyle of Kyle Communications, who set this up at his own expense........

 

JimG

 

 

[Kyle Communications]

Just to inform everyone the Simplex repeater is currently off air...it has developed a fault I will be changing the type of radio used so it will be back on air soon...better than before I hope. When you build a first of type there can always be a few issues

 

Mark

 

 

[facthunter]

Clever idea. Not sure I would want to hear what I sound like. Nev

 

 

[Kyle Communications]

Hi Nev

 

There are so many bad radio transmissions around here it isnt funny. With this you have to believe it as it replays back exactly what it hears. Often times I hear other pilots commenting to other pilots with a crap radio transmission and none seem to believe the other guy...they must think it is not their radio at fault. This way there is no confusion with what you are hearing.

 

 

[facthunter]

It's a really good idea. A full R/T test was normal at a controlled airport in the pre flight . ( including HF.). Nev

 

 

[DonRamsay]

Mark, what would it cost to purchase such a setup?

 

There are plenty of bad radios around the lower Hunter Valley and three clubs that could pool resources and install such a system.

 

 

[Kyle Communications]

Hi Don

 

It requires a airband radio a simplex repeater module and of course a power supply and of course a few hours to install the module and test it....you also need software and programming lead to program features and functions in that module. A secondhand radio can reduce the cost dramatically BUT some radios are easier to modify for the use of the repeater module. I had a Icom A110 they are a fantastic base radio but did not modify easily I had a lot of issues interfacing the module. I have a second hand Icom IC-A200 here this looks a lot easier to modify so will see how it goes. The other costs are the government costs. Airservices charge a $270 allocation fee then the first year is $115.00 then each year after that it is $40.00 per year so the first year you are up for a total of $389.00 and a bit of paperwork of course.

 

Mark

 

 

[Kyle Communications]

Oh I almost forgot air services also required a PTT timer and also a bandpass cavity to be installed in the output

 

 

[cooperplace]

Oh I almost forgot air services also required a PTT timer and also a bandpass cavity to be installed in the output

this is a great idea, I wish there was one everywhere

 

 

[DonRamsay]

Thanks Mark. You would think that AirServices would be willing to wave some fees here to encourage better radio comms.

 

I'll definitely be proposing this to a few of the local clubs.

 

A mate of mine has set up a weather station at his home airstrip and put it up on the net. Great for him when heading home to see exactly what the weather is doing at his destination. It was not get expensive to establish and a lot more clubs could do likewise especially as the AWIS network is being shrunk.

 

 

[Guest Andys@coffs]

Mark

 

I followed your answer to Don, but don't think it was a full answer. If I came to you today and said commercially Mark how much to buy this solution from "Kyle communications" what would your answer be? (commercial not freebe's)

 

I'm trying to understand if we are talking $2k or $10k or $100k......

 

Andy

 

 

[skeptic36]

You would think that AirServices would be willing to wave some fees here to encourage better radio comms..

No, they should be setting them up themselves (air services)

It should also be a function of our organisations (raaus, hgfa, asra, saaa and whatever groups G.A have) to lobby for these sort of things.

 

Is their a union which encompasses all these groups to give us some traction with the governing bodies or are we divided and conquered

 

Regards Bill

 

 

[DonRamsay]

Very good point. Perhaps you would like to ask your Board Rep to bring this up with the rest of the Board and have RAA DO something about it?

 

 

[skeptic36]

I'm HGFA, but I will talk to them about it.

 

Regards Bill

 

 

[DonRamsay]

Thanks Bill.

 

I'll pass it on to my Board Rep(s) at RA-Aus.

 

 

[Kyle Communications]

Hi Andy

 

I was a bit vague about the pricing...if you used new equipment you are looking about $1500 for the radio about $200 for the simplex module around $300 to do the interfacing and programming of the module. Base station antenna around $350 the coax and connectors around $100.00 and a power supply to suit $200.00. Air services will want a cavity on the output so that is around $600.00 for a decent one with a narrow bandwidth also a PTT timer circuit which would need to be installed in the radio that is in the interfacing price

 

Total somewhere in the region of $3200 to $3500 total for the hardware NOT including licensing fees or site fees etc

 

Mark

 

 

[Guest Andys@coffs]

Then your a star for putting that together for $0 cost to anyone else... Well done!

 

Andy

 

 

[Guest Andys@coffs]

I don't understand the need for the cavity though, what's the thinking there?

 

 

[Kyle Communications]

I dont know about a star Andy but I like to do a few public help projects. I also have 3 UHF CB repeaters I run at our radio sites as well they are a public access service although mostly not appreciated by some users but in general provide a good service except for a few idiot loudmouths although this is the same everywhere now I am not on my lonesome with that.

 

Airservices want to make sure the bandwidth of the signal is not too wide as it is AM as you know and the signal is a lot wider than FM and can produce some sidebands. This way any unwanted carrier is sawn off. The cavity I used I think I posted a pic of it when I swept it was pretty reasonable. I think it was around 10 or 12db down at 2 mhz either side of the centre frequency. They also wanted a PTT timer so it could never lock on with a permanent carrier

 

I also have it on a remote shutdown as well I can turn it off or on from my mobile or a desktop computer. We have a microwave mesh covering from Mt Cootha in the centre of Brisbane up to 2 sites at Maleny also a mesh hub at Mt Mee and Ocean View where the simplex repeater is . I like to be able to shutdown remotely any of our gear just to be on the safe side and with the internet control stuff and linking gear so cheap now it makes it easy to do so.

 

Mark

 

 

[Guest Andys@coffs]

After posting my thinking was that the cavity fixes the Tx frequency so that in effect no matter what is dialed up (or misdialed up) only when at 131.375 would useful power be radiated. The concept of having to narrow the radiated bandwidth of a radio that is on the ground when the same radio is in the air without the cavity is an odd concept to me, when in the air the ability to Tx greater distances etc is much more likely.

 

Anyway Im sure it does something.....for cavity manufacturers....

 

Andy

 

 

[Kyle Communications]

You hit the nail on the head Andy...I questioned it as well and the answer was ...you WILL have a bandpass cavity in the output or it wont be licensed

 

 

[Kyle Communications]

Simplex repeater should be back up and running tomorrow sometime at Ocean View. Please give it a try

 

Mark