Untainted123
Well Known Member
Anyone recognize or have a possible wiring diagram for this arrangement? It's coupled with a PSE PM1000II intercom.
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Poor Man's Audio Panel
- Thread starter Untainted123
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Or - if you have some fine soldering skills, you can build your own AP-60 or similar for $2 in electronic parts. All the costs are for connectors, etc.
So to answer the OP:
Most likely the switch on the right feeds mike and PTT outputs from the PSE intercom to either radio 1 or 2, as selected (e.g, a double pole, double throw switch).
The left switch either feeds the audio out from both radios to the intercom, or just the radio selected by the right switch (auto).
I did this on two planes with Dynon's intercom. As long as you make sure to have the mic matched up with the audio, it works well. Not so good if you're listening to com2 and inadvertently transmitting on com1.
Untainted123
Well Known Member
Unfortunately I don't have the plane anymore, or I would just take it apart and see. I had hoped it was some common wiring that people did back in the day and had a schematic for, because I kind of liked the arrangement, and wanted to see about duplicating it in another plane, without buying a complete ($$) audio panel to add a 2nd comm.WAG without more info...
comm1/comm2 switch is routing ptt switch to either radio
both/auto implies a home made circuit due to the "auto"
check back of the switches to see where the wires go- hopefully you have a tip up canopy to make that easy to do.
This really isn't the same thing, I don't want to have to turn up and down radio volumes.
What is the "this", this switch arrangement? Or one of the other suggestions.
This arrangement was nice because of the "Both/Auto" switch, which is the part I am most curious about. The TX1/TX2 seems straightforward (switch the Mic/PTT), as BobTurner says, but I am wondering how the TX switch is wired to the Both/Auto switch so that it "follows" the TX switch...
One way is for the right switch to be 3 pole, double throw, where the extra pole switches between the receivers’ audio outputs. The left switch is just a 1 pole, one throw switch. In ‘off’ the switch is open, this is the ‘auto’ position. On ‘both’ the switch is closed and shorts the two receiver audio outputs lines together. Put an 330 ohm resistor in each audio output line, so the two receivers don’t fight each other.
Pilot8
Well Known Member
See post #6 for a schematic. Your auto mode is still a mystery- a dc level detector using diodes as the mixer might work but that's only a guess; the both mode would use the resistors as the mixer.
forum.flydynon.com
Audio Panel
I have a small, tandem two-seat airplane with a very small panel including one radio panel and one intercom panel. I want to add a second radio panel and think I'll have to use the intercom panel space for it. That means I need to find a place for an audio control panel or function including...
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Untainted123
Well Known Member
Norman CYYJ
Well Known Member
Yes that is the way to wire a poor man's audio panel for two comms
Also possible that auto feeds selected com audio out to intercom audio in and both sends the selected com as above and the other to the unswitched audio input of the intercom. This is lossless with no resistance required. Mine is similar, but more elaborate, as i also have option for nav audio. I used the traditional audio input and the unswitched audio inputs for mixing two streams. Most of the pm series have an unswitched input.
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Untainted123
Well Known Member
I'm not sure that's right either. You don't want a 330 ohm resistor on your audio output all the time, do you? I think you only want it there when you have both audio signals connected together...
Untainted123
Well Known Member
I thought the same, thus the original version, but I am not really an audio guy, so I don't know for sure. I would think the first version only needed protection when they are connected together, not all the time like the 2nd version.
Larry, can you elaborate on this more? As in, what kind of switches and what goes where?
vlittle
Well Known Member
The 330 ohm resistors (I use 150 ohm, but the values are not critical) allow both radios to be heard when the the on/off switch is ON. Otherwise, only the selected radio will be heard. Shorting the two radio Comm outputs directly together is not recommended, although the Garmin SL-40 radios are ok with this.
Attachments
Untainted123
Well Known Member
So I learned the reason for having the 330 ohm resistors be inline with the output from the radio is so that the volume is already set when you switch to both, instead of having the volume fade when switching to both. Having them there makes you go ahead and get your volume right when on single (ie Auto) and it stays at the same level when switching to Both. So the correct version is correct.
Thanks for everyones input!
A thought on "Auto" setting... it may just indicate that the transmit switch also controls the Rx. Auto being: if XMT is set COM1, then RX is also COM1. If XMT is set COM2, the RX is also COM2. Which is nice as it avoids needing to flip two switches and reduces chance of transmitting split (i.e. XMT com1, RCV com2) by accident.
Untainted123
Well Known Member
That is correct, which is why I like this arrangement. This arrangement is also useful if your radios don't have a standby (most do these days), you can use Both to monitor the other radio; or if they do have standby, you could in theory monitor 4(!!) conversations.
These days, with most radio's having a standby function, you could probably just eliminate the Both/Auto switch and not really lose any practical functionality, Whatever setting the Com1/Com2 switch is in is fully which radio you are using.
When I had this setup, I would stage up 4 frequencies and roll through them, and rarely used both, EXCEPT the standby on GTR's ducks under the main freq, and sometimes I literally wanted to hear both voices at the same time at the same volume, so I would use Both in those situations.
This is exactly correct. For me, coming home to LVK, NorCal approach is very busy. Putting the ATIS on the standby frequency it takes 10 minutes to get it all, in little pieces at a time. Putting it on the second radio and listening to both works. Human ear is pretty good at listening to ATIS but switching focus if you hear your call sign on the other tadio.
I have one come (with a second standby receiver ICOM 220A. So I am not dealing with two Transceiver But do have a handheld I can use for "emergency". That requires me to plug headset in directly to handheld and use the attached antenna... or plug the audio into the aux jack on the panel, and use the onboard transceiver mic. I doubt range would be great, without plugging into the aircraft antenna, I don't have a way to easily access the coaxial.
I do have a DRE intercom with aux audio input. So I use that for music and warning, and aux input (handheld above).
To MIX three audio inputs (music, warnings, aux) I bought inexpensive mixer op amp. I am thinking adding in a BlueTooth receiver to add into mix..
I do have a DRE intercom with aux audio input. So I use that for music and warning, and aux input (handheld above).
To MIX three audio inputs (music, warnings, aux) I bought inexpensive mixer op amp. I am thinking adding in a BlueTooth receiver to add into mix..
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What about the antenna with this setup?
EDIT: nevermind, found this thread: https://vansairforce.net/threads/a-single-com-antenna-used-for-dual-com-radios.169901/
EDIT: nevermind, found this thread: https://vansairforce.net/threads/a-single-com-antenna-used-for-dual-com-radios.169901/
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Hi.
After about ten year of flying my -8, I desided to add another radio to my A/C.
I had to make a kind of Mixer and TX select SW/ So I desined and built my own mixer and added a TX selector SW/
Attached you can find the DWGs.
Feel free to use the schematics.
After about ten year of flying my -8, I desided to add another radio to my A/C.
I had to make a kind of Mixer and TX select SW/ So I desined and built my own mixer and added a TX selector SW/
Attached you can find the DWGs.
Feel free to use the schematics.
Attachments
vlittle
Well Known Member
About 20 years ago, I developed the AMX family of audio mixers…. See https://www.huvver.tech/open-source-hardware/
These are made and sold by MakerPlane in mono (AMX-2A), stereo (AMX-4A) and mixed (AMX-10A). Take almost no space and are easy to mount.
vlittle
Well Known Member
The issue is the cost of shipping, taxes, and tariffs for US destinations. It costs more to ship to US destinations than the cost of building the devices. For the time being, I am supporting business OEM customers who have their own Fedex accounts and will bear the additional costs and paperwork. Customers within Canada are much easier to support, but I am currently out of stock (and out of the country) so will be a few months before I have more inventory.
The audio mixers have been a runaway best seller (hundreds) since I introduced them in 2008. Back then, the cost of shipping to the USA was $2.00. Now, add a couple of zeros to that cost for shipping, paperwork and tariffs! The solution to this is to find a US Supplier willing to pick up the product line, but so far no luck.
Norman CYYJ
Well Known Member
Hope you are enjoying this nice wx Vern.
Thanks Vern, what about those of us outside the USA? I think shipping to Switzerland will only cost 5 CAD if it's less than 50g if I read the Canada Post website correctly.... Otherwise up to 1kg it's about 30 CAD. I get that shipping is a hassle, even more these days...
vlittle
Well Known Member
As I said "I am currently out of stock (and out of the country) so will be a few months before I have more inventory".
You might have luck contacting MakerPlane. Even though their store is closed, they may have some devices that they can ship overseas.
Vern
vlittle
Well Known Member
Yes I am.... but currently recovering from PickleBall injuries!
Norman CYYJ
Well Known Member
That seems to be a common ailment with the seniors around here also.
This is not as hard as it seems. Buy some ‘vectorboard’ or other trade name. This is a piece of fiberglass or bakelight which has a large number of pre-drilled holes on 0.1” centers (standard IC spacing). Each hole will have a ring of copper around it. Insert the IC (s) and components from the top side. On the bottom side, bend the leads from the resistors and capacitors to the IC pins where they belong, and solder the leads and pins to the copper circle. With forethought, many of these leads will only need to be bent over to one, or maybe two, nearby holes. There will be a few places where an insulated jumper wire will need to be used. Not nearly as elegant as a PC board, but it can be done.
pjc
Well Known Member
Thanks Bob,
No doubt I could build a functioning sample this way, but Vern’s elegant design mounts the entire device (fairly densely) inside a 25pin D-sub shell. That’s much of the attraction, but beyond my skill level using perf-board/vectorboard.
Peter
