Enable the CM4's external antenna connector (dtparam=ant2)
One line in config.txt switches a CM4 from its on-module PCB antenna to the u.FL connector the uConsole's antenna is actually plugged into.
What it takes
- Config change
Difficulty 1 of 3 — easy.
Details
The Compute Module 4 defaults to its own PCB-trace antenna and leaves the external u.FL header disabled, so inside the aluminium uConsole the antenna ClockworkPi fitted is doing nothing. NanoCodeBug's fix is dtparam=ant2 in /boot/config.txt followed by a reboot; the thread links Jeff Geerling's write-up of the same parameter and the Raspberry Pi forum discussion behind it.
Most owners report a large improvement; a few saw no change or worse. The OP's own caveat is that the u.FL plug on the module must be properly seated, so check it while the case is open. This is a CM4 quirk only — the A-06 connects its antenna to the mainboard, and the parameter does nothing there.
Links
Open at Forum threadRelated mods
Swap the stock foil antenna for a u.FL-to-RP-SMA pigtail, a small dual-band whip and a printed mount, with three years of measurements behind the choice.
The zero-cost fix: a scrap of plastic or foam tape between the foil antenna and the aluminium body, plus a re-routed lead, is worth 10–15 points of signal.
A screw-mount SMA bulkhead passed through the case's existing cable slit and nutted from inside — an external antenna with no drilling and no printing.
A tape-on printed hinge that holds the antenna flat for carrying and folds it up, clear of the metal body, when you need the signal.
A printed replacement for the stock antenna cover that hides a full-size dual-band Wi-Fi antenna and an LTE antenna behind an engraved 'uConsole CM4' panel.
A slimmer plastic backplate that helps Wi-Fi by getting the aluminium out of the way and hides extra radio hardware, with a matching antenna side compartment.