Can an aviation band dashboard be added?

[mengzi0727]

Can we join the aviation band? People can achieve reception by connecting an external frequency converter, which makes the interface operation more intuitive.

35a627071c7418a8687a95ac462199cf.mp4

[max-arnold]

What frequency offset is the most common in these downconverters?

[mengzi0727]

Usually it is 100 MHz.

[G8PTN]

Hi Max,
Others are using the 110 MHz version.

The “superogira” fork was configurable, which is probably the better way to go.
Also, consideration will need to be made for the steps and display resolution.
One of the steps used in aviation is 8.33kHz, which can’t be supported.
If people want a converter for VHF (SSB), the sub-1kHz digits may still be desirable.
#120

73, Dave

[max-arnold]

Since we now have Squelch option, I can consider adding this feature after the EEPROM is switched to Preferences #94

Another implication is Memory slots that will have incorrect references to bands if a new band is added

So this has to wait for some time

[mengzi0727]

Looking forward to it. Thanks for your hard work, big guy!

[max-arnold]

@mengzi0727 Could you please share a copy of the Chinese firmware displayed on your first photo?

[mengzi0727]

What I mean is that the FM searching function of your firmware is inaccurate. You can make a comparison. I don't have the drawings.

[max-arnold]

For me both firmwares skip stations in search mode.

[EmEiBee]

I've noticed this effect also, regardless of whether it's on shortwave or FM.
Since I don't know anything about programming, I can only assume that it's looking for a fixed level jump. It would probably be better, though, to calculate a moving average while searching...
But as I said, I have no idea...

[mengzi0727]

对我来说，两种固件都会在搜索模式下跳过电台。

11ce89265671c49c9dc4061aa465988d.mp4

The difference is remarkably clear.

[max-arnold]

It is hard to say what is different in how the search is implemented in the firmware on the video without the source code.

The available source is for an older Chinese version with a different UI #28

Does it perform as well for you?

[G8PTN]

Hi Max,
Perhaps have a look at the spare IO pins of the ESP32 module on an oscilloscope.
I suspect one of the pins will be a PWM output, which would need low pass filtering and then used as the audio output.

The readme file talks about IO14, but it implies it goes “high” when the network radio starts, so could be used as some sort of enable/disable signal.

Excluding the RXD0 and TXD0 pins, IO11, IO12, IO13 and IO14 are spare according to the original hardware.

Alternatively, the firmware may be geared up for an I2S audio device which would allow both audio in and out capability.

73, Dave

[max-arnold]

The binaries contain references to the following library https://github.com/schreibfaul1/ESP32-audioI2S that requires something like MAX98357A

[G8PTN]

Hi Max,
Yes, I did play around with a MAX98357 some time ago using an ESP32-S3 dev module and a few on-line examples.

I also tried a cheap I2S microphone module INMP441. I think the example I used streamed the audio in "Wav" format to a web browser.

Perhaps if the ATS-MINI hardware was updated, it would be better to have both in/out capability, so that the audio from the receiver could be processed and/or streamed over WIFI. I think I2S was relatively resource intensive and made use of the external SRAM.

PS: There is another ESP32 module called "ESP32-A1S", which has a built in audio CODEC.

73, Dave