Experimental AM/SSB SI4732 patches

[max-arnold]

The ATS Mini firmware v2.41 added support for @NeekeetosNee's experimental SI4732 AM/SSB patches (link): you can now upload them over Wi-Fi without rebuilding the firmware.

Store up to three patch sets and switch between them from the web page or receiver menu for easy comparison.

1. Enable Wi-Fi on the receiver and open its web interface.
2. Open the Patches page.
3. Choose an inactive slot: Custom 1, Custom 2, or Custom 3.
4. Select AM or SSB, choose the matching .bin patch file, and click Save. Repeat for the other mode if needed.
5. Activate the set on the web page or through Settings → DSP Patches on the receiver.

Missing modes use Default; FM is unaffected. To replace patches in the active slot, select another set or Default first.

To remove a set, check Delete set and click Save.

---

V1

These experimental patches reduce tuning bursts (“chuffing”), giving the receiver a more analog-like tuning experience. Slight clicks may remain.

Normally, retuning stops the DSP while the chip calibrates its internal RC oscillator for the new frequency. The patches replace the slow calibration search with a lookup table, calibrated to the oscillator at startup. This speeds up frequency changes and allows the DSP to keep running during tuning.

---

V2

These experimental AM and SSB patches reduce tuning interruptions by keeping the DSP running without forcing the volume to zero. After initial calibration, a lookup table speeds up oscillator tuning, while filtered background corrections maintain accuracy.

AM

• Faster seeking while preserving the standard signal-quality measurement interval. Median seek time fell from 288 to 137 ms in the tested series.
• Manual tuning resets accumulated AFC correction without resetting AGC.

SSB

• New Weaver demodulator with FIR filtering, decimation, and six selectable bandwidths for USB/LSB.
• Corrected frequency and BFO calculations, referenced to the external clock rather than tracking the received carrier.
• Main AGC and RSSI operate after the channel filter, with a separate early-stage gain limit to prevent overload.
• I²S output carries identical audio on both channels. It currently uses sample holding, without full asynchronous sample-rate conversion.
• Volume and mute controls are preserved. Bandwidth changes briefly stop the DSP to load filter coefficients; normal RF tuning does not.

---

Patches in compact binary format are attached.
patches.zip

[EmEiBee]

Ähem....
How to install the patch? Extracting and uploading via ATS-Web-interface? Only one? Or one after the other?
Sorry... just lost right now... :(

[max-arnold]

Sorry! Added a short guide to the initial post.

[EmEiBee]

Ty for the fast response... But I haven't an "Patch" item... FW 2.4.0 from 19 Sep

[max-arnold]

You need to install a test F/W build from the link above. It's not yet released.

[EmEiBee]

Ufff... ... well, why didn't you say so in the first place? LOL
Ok, all well... I try the correct way then ;o)

Ty a lot

[radiola2]

This is the best thing ever for the Si4732 radios. Much better without the annoying chuffing.