Some basic radio avionics questions

kicktireslightfires

Pre-takeoff checklist
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kicktireslightfires
Few quick questions I was hoping to clear up in my general knowledge:

1. I'm a little confused by this radio setup from Dynon. What's the purpose of the panel on the left when you have the panel on the right? Other than the audio jack for the music in, of course (but I have no need for that as I'll be routing the music directly into the A20's Bluetooth).

2. What's the APT button on the radio panel? Is that the same thing as the monitor button on a Garmin radio allowing you to listen to both your active and standby frequencies at the same time? If so, what does the APT stand for?

3. What's the "Push SQL?" I"m assuming that means push to squelch, but I'm not sure what that means. Why would you want to push to squelch?

Thanks in advance!

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Looks like the APT knob selects the airport shown in the APT display, which then sets the frequencies based in which button you press (TWR, GND, etc.). Quicker and fewer steps involved than looking it up and dialing each frequency.
 
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Probably want to go read the POH section specifically about the Dynon radio.

1- The left is intercom control, the right is radio control. They accomplish very different things.
2- Used to select the "APT" entry, so you can spin in an aiport ID and lookup the frequencies.
3- If you're just far enough away that you can't quite hear the radio, push to squelch is a common way to ensure you hear it. Super useful for weaker ATIS/AWOS
 
Probably want to go read the POH section specifically about the Dynon radio.

1- The left is intercom control, the right is radio control. They accomplish very different things.
2- Used to select the "APT" entry, so you can spin in an aiport ID and lookup the frequencies.
3- If you're just far enough away that you can't quite hear the radio, push to squelch is a common way to ensure you hear it. Super useful for weaker ATIS/AWOS
Don’t you push to set it to squelch mode and then turn the knob to adjust?
 
Don’t you push to set it to squelch mode and then turn the knob to adjust?
Been a while since I flew with that (or other Dynon radios) but I believe it's just like pushing the "Push SQ" button on a 430/530. Push in=open squelch.
 
By the way the knob on the left unit (intercom), pushing the button ins't squelch it turns on the "auto mute" feature that kills the music when someone speaks into the intercom. It's the opposite of what some other manufacturers call Karaoke mode that allows you to sing along with the music.

Here's the manual for the intercom: https://www.dynonavionics.com/inclu..._Installation_and_Pilots_User_Guide-Rev_A.pdf

They describe the COM radio in the paired integrated display manual (example here: https://www.dynonavionics.com/inclu...ssic_Touch_Pilots_User_Guide-Rev_AB_v15_4.pdf see chapter 11).

The SQ knob is a momentary "press to open squelch" feature. This is the opposite of many other radios where you pull it out to open the squelch (and it stays out).
 
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Thanks all! Guess I still don't understand the purpose of the intercom control if you have the radio control. The radio control has the volume knob and squelch control on it. Only thing the radio control doesn't have that the intercom does have is the AUX music in port. Is that correct? So if I have no plans to use AUX for music in and instead will be using Bluetooth to my Bluetooth enabled A20s, then is there any point to having the separate intercom control?
 
The intercom volume affects the level that other people talking into headsets come through as part of the intercom feature. It doesn't affect the radio volume. The radio volume affects the level of the radio.
The squelch on the intercom likewise affects how loud a headset microphone signal must get before the intercom allows it to feed into the headsets. The radio squelch controls how strong the received transmission must be before it is sent to the headsets. The intercom also has a "mute" feature that cuts out the music input when the radio or someone is speaking (which you can turn off).
 
The intercom volume affects the level that other people talking into headsets come through as part of the intercom feature. It doesn't affect the radio volume. The radio volume affects the level of the radio.
The squelch on the intercom likewise affects how loud a headset microphone signal must get before the intercom allows it to feed into the headsets. The radio squelch controls how strong the received transmission must be before it is sent to the headsets. The intercom also has a "mute" feature that cuts out the music input when the radio or someone is speaking (which you can turn off).

Ah, thank you. I think I understand now! So the value of the intercom panel really only applies when you are flying with other people and want to adjust the comfort parameters of the headset inputs? If I'm by myself, so long as I'm not talking to myself (LOL), it really wouldn't have any utility if I'm not using the music mute function? And come to think of it, since the Bose A20s have an in-line volume control on them, it really wouldn't be a factor then either if both myself and a passenger had an A20 headset on as we have our own separate volume controls right on the headset themselves?
 
And come to think of it, since the Bose A20s have an in-line volume control on them, it really wouldn't be a factor then either if both myself and a passenger had an A20 headset on as we have our own separate volume controls right on the headset themselves?

The intercom panel controls squelch for the mic. So you'd still want to set it appropriately for you/passengers. Too high and you/passenger won't be loud enough to be heard. Too low and the mic will always be open.
 
Once a newbie starts learning to fly, an awful lot of questions get answers real fast. Stuff that seems stupid suddenly looks wise. Many thousands of aeronautical engineers and aircraft and engine manufacturers and pilots have all learned a lot of stuff the hard way over the years, and what we see in airplanes now is the result of a desire to avoid any further death and destruction and inconvenience and hazards and grief.

The real shortcomings now are in pilot training, not aircraft design and construction.
 
The issue is not that he's a newbie, and not that he has questions, but a lot of this could be satisfied by reading the manuals (which I provided the links for in addition to the answers I gave).
 
The issue is not that he's a newbie, and not that he has questions, but a lot of this could be satisfied by reading the manuals (which I provided the links for in addition to the answers I gave).
True about reading the manuals. However, the manuals are typically written by someone that knows how the system works and therefore might not present the information in a manner that someone that doesn't will understand without asking questions for clarification. I tend to find that with the Garmin manuals as I'm not fully up to speed with their logic/thought process.
 
Typical manual

1) volume knob. This knob controls the volume.



thanks for all the help.
 
And come to think of it, since the Bose A20s have an in-line volume control on them, it really wouldn't be a factor then either if both myself and a passenger had an A20 headset

Not really. Your inline volume control would control the level of the final audio stream getting to your ears, but you will still want individual level controls for each audio source. Otherwise you will run into issues when encountering an audio stream with a low-level audio. For example, an ATC that speaks softly, or a distant NAV source you are trying to hear. You can increase the level of the radio without blowing out your eardrums when you passenger accidentally coughs into the microphone.
 
Typical manual

1) volume knob. This knob controls the volume.



thanks for all the help.

Yep - I'm just getting to the point where I can actually get something out of reading avionics manuals. (>300 hours in) It really makes little sense until you've used the avionics some. To the OP - it will all start to make sense as you use the stuff. For example, the squelch question will make more sense when you are trying to get an ATIS from 50 miles out or identify a VOR.
 
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