Dual Dynon radios and PM1000 circuit diagram

[jaba-who]

I’m in the process of building a Jabiru 430 needing 4 place intercom to go with my dual dynon radios. Although I’d prefer all Dynon to go with all the other instruments I’ve got to go with a non-dynon dedicated 4 place - planning on a PM1000 II

anyone got a circuit diagram for a working set up with HDX, two dynon radios and a pm1000II?

 

[Rhino]

As an intercom, the PM1000 only supports one radio out of the box. The PMA4000 has the same form factor, and supports two, but it's considerably more expensive. It gives you other capabilities as well, but all that may not be worth it to you. It is possible to use a PM1000 with two radios, but it will require somewhat significant custom work involving panel switches, a mixer (maybe two), and some creative wiring. That route may be preferable to you if you're really into that kind of stuff, but many aren't. I could help with wiring either way, but you have to decide which way to go, and what features you want. Personally, I'd spring for the PMA4000, and I'm a techno-geek. The cost of the mixer and the headaches of all the custom wiring would be worth the extra cost of the PMA4000 to me. But that's just me.

 

[jaba-who]

Thanks for that. I’ve just had a look at the PMA4000.
The issues I see are that the 4000 is double the price here in Australia. $1000Aus vs $2000Aus.
I’d be paying for stuff I’m never going to use. The 4000 has nav com 1 and 2. I have never had and never used a nav com device. In Oz the ground stations for aviation beacons are being phased out ( if they haven’t already all been ).

I previously made, wired and ran for a decade or more a PM501 with two Microair 760s radios. That involved a bit of wiring loom I fabricated and just a double ganged rotary switch that selected for a single radio input on transmission. As best I recall the M760 to be used as Comm 2 needed a mod back at the factory to be able to use it as a dual system. Don’t know if the Dynon radios need any sort of tweak as well ( or is that what the mixer is for? )

I was hoping I might be able to go down that sort of path again. So I’m not averse to an extra panel switch. I was expecting it.

Not sure about the mixer though. Haven’t had to deal with that before.
But still might be cheaper than a 4000.
Could you briefly outline the actual role of the mixer?

In the grand scheme of things I’m not after much just 4 headset intercom access and two comm radios - listen on two, transmit on one or other as needed, get audible warning tones etc from the Dynon
I don’t use music inputs or other audio devices in flight.

If it came to needing some wiring and panel switch/s that’s what I was expecting. The idea of a mixer is not necessarily a deal breaker.

 

[jakej]

Jaba- you can go down that path again, i have done that several times. I use a PM1200 & the AMX 2/10A ( Maker Plane) with a 3PDT switch for the TX. I’ll send you a text.

 

[Rhino]

One of the functions an intercom or audio panel performs is mixing audio. If you simply tie the audio from two sources directly together, bad things usually happen. That's what mixers are for. Since the PM1000 doesn't have a mixer to combine audio from two radios, you'd need an external mixer, like the AMX-2 or AM-X10 that Jake mentioned. Those are actually designed by a member here, and have a long track record. They also have inputs for other audio devices, should you change your mind in the future. The switching would be the hardest part, but not all that hard. And since you've done something like this before, you shouldn't have any real problem. Just to give an idea, this is something similar that I did before;

It doesn't match your setup, but it demonstrates the concept. There's a thread on it around here somewhere. Changing it to a PM1000 wouldn't be difficult. Adding two seats would also be very easy, as long as you don't expect them to transmit. The AMX-2A is currently $129.95 USD each.