P

Pilottonny

Well Known Member
I am currently wiring up my radio and audio connections and am confronted with the following signals to be wired to the intercom:

- SL30 com. ? OK no problem, the manual is pretty clear, how to connect up.
- SL30 nav ? not sure, if there is a way of internally getting the signal to the com side? Need to check the manual on this. If not, I need to wire it to a switch to toggle between Nav/Com, should not be a problem.
- Dynon Voice alerts ? Problem 1: This is just one wire from the HS34? if I use the Dynon ground, for the second wire, I may have a problem with ground loops? I need to swap the single wire for a shielded wire also.
Problem 2: where do I wire it to? If I wire it to the music input, I will no longer be able to use that input for an Ipod or CD-player, right? The second music input on the PM-1000 II can only be heard by the passengers not by the Pilot and co-pilot!?
- GTX328 Transponder ? There is a few voice alerts from the transponder also. Where do I wire the transponder Audio to? Parallel to the Dynon? I am not to worried about this, I could live without these voice alerts and make things simpler, anyway.

As always, many thanks in advance for your input. Tonny.
 
PM3000A Unswitched inputs

Dear Tonny:

There are no unswitched inputs on the PM1000II, so I'm sorry to say that there is no way of connecting these alerts to your current intercom.

You might consider the PM3000A which has two unswitched inputs that were designed specifically to handle the types of inputs you are trying to connect.

www.ps-engineering.com/pm3000.shtml

Sincerely,
Mark Scheuer
PS Engineering

Pilottonny said:
I am currently wiring up my radio and audio connections and am confronted with the following signals to be wired to the intercom:

- SL30 com. ? OK no problem, the manual is pretty clear, how to connect up.
- SL30 nav ? not sure, if there is a way of internally getting the signal to the com side? Need to check the manual on this. If not, I need to wire it to a switch to toggle between Nav/Com, should not be a problem.
- Dynon Voice alerts ? Problem 1: This is just one wire from the HS34? if I use the Dynon ground, for the second wire, I may have a problem with ground loops? I need to swap the single wire for a shielded wire also.
Problem 2: where do I wire it to? If I wire it to the music input, I will no longer be able to use that input for an Ipod or CD-player, right? The second music input on the PM-1000 II can only be heard by the passengers not by the Pilot and co-pilot!?
- GTX328 Transponder ? There is a few voice alerts from the transponder also. Where do I wire the transponder Audio to? Parallel to the Dynon? I am not to worried about this, I could live without these voice alerts and make things simpler, anyway.

As always, many thanks in advance for your input. Tonny.
Click to expand...
 
Very strange!

Very strange indeed! This afternoon there was a post, that is now gone!

It was somebody (sorry can not remember who it was), that mentioned it was not a problem to connect the Dynon to the PM1000 II !

Where are you ???

Please come back!
 
Very strange indeed!

Very strange indeed! This afternoon there was a post, that is now gone!

It was somebody (sorry can not remember who it was), that mentioned it was not a problem to connect the Dynon to the PM1000 II !

Where are you ???

Please come back!
 
Unswitched inputs?

Mark,

What are "unswitched" inputs? According to the PM3000 manual, the "unswitched" inputs are the same pin-numbers as the #2 music input. But, the #2 music input can not be heared by the pilot (only by the passengers!). Why would I need a PM3000 ?

The poster (that misteriously disapeared today), mentioned that he had a wiring harness from Stein-Air that alowed the conection of the Dynon to the music input of the PS-1000 II. I guess he would have used a potentiometer, as per Dynon manual to get the 8 V down to max 2 V?

Anybody got any more ideas, or is using this setup?

Tonny
 
Tonny, your problem with connecting a number of audio inputs into an intercom is why the AMX-2A was developed.

The AMX-2A has ten inputs, four of which are variable (good for connecting to Dynons for example), and six are fixed.

It can connect to any intercom, with or without an auxiliary input. All of the shielded wires terminate directly on the device, and the audio output connects directly to the intercom, or can drive headphones.

For more info: www.vx-aviation.com.

Thanks,
Vern
 
SL 30 has internal fix for NAV audio!

Vern,

Thanks for pointing it out, but I investigated some more. The SL30 has a feature that lets your hear the NAV identifier (morse code) through the COMM. So that is no longer a problem.

I am not bothered with the transponder allerts. So I am left with the Dynon allerts. After reading the "disapearing post" I realised that it was also Stein-Air that advised me to get the PM-1000 II for the Dynon allerts. I will do the same as the poster did, connect the Dynon to the Music#1 input. It's a shame that I will no longer be able to use the #1 music input for music, though. I was going to surprise my wife with her own entertainment center (Ipod) in the plane. Unfortunately the #2 music input can only be heard by the "passengers", not the pilot or co-pilot.
 
Okay. I am entirely guilty of pulling the disappearing post. It was I who installed the PM 1000 II and associated wiring harness assembled by SteinAir. As I mentioned, I am not one to listen to inflight music so I connected all audio outputs from the various accessories including an IE MVP-50 engine monitor, AOA, and Dynon D100 into the music circuit on the wiring harness after snipping off its jack plug.

To do this successfully I contacted, then simply followed the advice of avionic guru John Stark:

"Each intercom has a phone input. You will need to run each audio wire through a 220 ohm resister and then to the com phone audio input of the intercom. Nav, com, AOA etc. will run through its own 220 ohm 1/4 watt resister (you can pick them up at Radio Shack) and then to the com phones (radio) input of the intercom."

Why PS Engineering says this is not possible with the PM1000 II intercom is unclear to me.
 
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Audio signals other than music and aircraft radio

Unswitched inputs are ones that are unity gain, are not muted, and are isolated from all other signals.

The PM3000A (11931A) has two inputs that are as described above.

The PM3000 that someone referred too (11932) is the 6-place intercom that does not have the unswitched inputs (no pins left to use for those inputs)

The PM1000II has only inputs for music (mono) and a single aircraft radio (or an audio panel).

The company that is selling the unit to sum audios would not have an appropriate input to use on the PM1000II.

Hope this helps.

Mark Scheuer
PS Engineering

Rick6a said:
Okay. I am entirely guilty of pulling the disappearing post. It was I who installed the PM 1000 II and associated wiring harness assembled by SteinAir. As I mentioned, I am not one to listen to inflight music so I connected all audio outputs from the various accessories including an IE MVP-50 engine monitor, AOA, and Dynon D100 into the music circuit on the wiring harness after snipping off its jack plug.

To do this successfully I contacted, then simply followed the advice of avionic guru John Stark:

"Each intercom has a phone input. You will need to run each audio wire through a 220 ohm resister and then to the com phone audio input of the intercom. Nav, com, AOA etc. will run through its own 220 ohm 1/4 watt resister (you can pick them up at Radio Shack) and then to the com phones (radio) input of the intercom."

Why PS Engineering says this is not possible with the PM1000 II intercom is unclear to me.
Click to expand...
 
mscheuer said:
...

The company that is selling the unit to sum audios would not have an appropriate input to use on the PM1000II.

Hope this helps.

Mark Scheuer
PS Engineering
Click to expand...

Hi Mark. The AMX-2A mixer/amplifier does not necessarily need an auxiliary input to sum various audio sources into intercoms.

The device works as an mini audio panel, and can directly insert audio into the comm input of any intercom. This is one of the key features of the AMX-2A: allowing expansion of auxiliary audio inputs for intercoms that do not support it.

For those who have downloaded the AMX-2A installation guide, it is Application "A".

Thanks, Vern
 
Sorry, I still don't get it completely!

Rick,

thanks for "coming out of the closet" ! I thought there must be a way of doing this "simple". Did you just parelell all these signals and hook them up to the comm input?, with a 220 Ohm resister on each wire? So I guess I could parelell the Dynon with the SL30 and connect them up to the phone input of the PM1000 II and still be able to use the music input for music, but.... if you just connect them together, will these signals not harm each others amplifiers?

Rick/Mark,

What about the single wire coming from the Dynon, do I need to connect the Dynon ground to the intercom? (which is also aircraft ground!) and will this not cause problems? Does it need to be shielded?

vern,

OK I understand that you want to sell your device, that will obviously do the trick. But, I hope you can understand my point of view, that if it is possible to do it without this device, it will be cheaper, lighter and less complex!

It looks like we are getting closer to the solution, thanks for your input!

regards, Tonny.
 
Pilottonny said:
.......Did you just parelell all these signals and hook them up to the comm input?.......with a 220 Ohm resister on each wire?......
Click to expand...
Yes, if you look close you can see a cluster of three audio outputs wired in parallel to the music circuit each fitted with a 220 ohm resistor.

​
 
Just resisters

Vern,

After looking at your manual and drawings, I think that your device does the same as what Rick is doing. Instead of 220 Ohm, you are using 150 Ohm resistors. (Plus an amplifier built in it, of course). I can not see the resistors on the inputs, but I guess from your discription, that the pots are 10kOhm, right? That is what Dynon is actually advising in their manual.

Rick,

I was thinking of installing the 10kOhm potentiometer instead of one of those resistors, to alow volume control of the voice alerts, as per the Dynon manual. Do you also have a potentiometer for volume control on the Dynon? The HS34 will put out 8 V! that will be to high for the intercom and also for the Comm and Nav.

Regards, Tonny.
 
10kohm pot

While I do not have the 1000 (I have the 3000) I wired the HS34 output per Dynon with the small 10k pcb mount pot from radio shack, wired it inline and covered with heat shrink except for the small adjust screw, worked very well. I also found a voltage divider circuit on the web that uses a few resistors that can be used to input the 496 speaker audio from the cable (rather than the back of the unit) into the same intercom input.
I think the volume adjustment is worthwhile to allow volume tuning.
 
Pilottonny said:
Vern,

After looking at your manual and drawings, I think that your device does the same as what Rick is doing. Instead of 220 Ohm, you are using 150 Ohm resistors. (Plus an amplifier built in it, of course). I can not see the resistors on the inputs, but I guess from your discription, that the pots are 10kOhm, right? That is what Dynon is actually advising in their manual.

Rick,

I was thinking of installing the 10kOhm potentiometer instead of one of those resistors, to alow volume control of the voice alerts, as per the Dynon manual. Do you also have a potentiometer for volume control on the Dynon? The HS34 will put out 8 V! that will be to high for the intercom and also for the Comm and Nav.

Regards, Tonny.
Click to expand...

Hi Tonny. The AMX-2A is a fully active device, where all of the inputs are isolated and amplified. Resistor summing works fine for a few inputs and another device we make (the AMX-1A) does use this passive mixing scheme.

After a few inputs, however, audio levels drop significantly and it's necessary to have some kind of amplification.

The output structure of the AMX-2A does use 150 ohm resistor summing for some applications where the intercom does not have an Aux input. In this case, only two devices are sharing an audio bus and levels are fine.

The variable level inputs of the AMX-2A do in fact use 10K ohm potentiometers to control volume.

Also, all inputs are capacitively coupled to remove any potential dc imbalance from the signals.

Look at the AMX-2A as you would an audio panel. No input switches unless you add them yourself, but it provides 10 isolated inputs, 4 of which are variable. Maybe not right if you a very simple cockpit, but if you add up all of the audio sources from EFISs, Engine Monitors, Traffic Monitors, AoAs, Navx, Comms and so on, you'll see why we developed it!

Thanks, Vern
 
SL30 and Dynon work fine now!

Hello Guys,

An update on my intercom wiring:

I wired the SL30 and Dynon in parallel, into the headphones input of the Intercom. It needs to be the intercom headphones input and not the music input, otherwise you would not hear the Dynon if ?iso? is selected on the intercom! At first, I used a 220 Ohm resistor on the SL30 and the 10kOhm potentiometer on the Dynon. Because I had to turn the SL30 completely open to get an acceptable audio level, I soldered another 220 Ohm resister in parallel with the first one (thus getting 110 Ohm), so that I have some adjustment beyond what appears to be the right level for now.

The Dynon sounds great. It works fine, even when both are working at the same time.

I did not wire in the NAV or the Transponder. The NAV can be selected internally on the SL30 (it will even do an automatic identification of the Morse-code) and the only voice alerts from the Transponder are: ?Timer expired? and ?Altitude?. I doubt that I will ever use these features anyway.

I wired in a receptacle for music input, that I still have to test (do not have the right wire available right now, to connect a CD-player ). So I can still use the music feature.

Thanks all, for your input, without it I would not have been able to make this work!

Regards, Tonny.
 
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