Does the G2 have Thermal Overload Protection?

[KC2QMA]

Does the G2 have Thermal Overload Protection to protect the P.A from over heating?

[Trucker]

The fan in my G2 Ultra runs all the time. I haven't read anything stating it does anything beyond that.
James
WD5GWY

[w-u-2-o]

I just looked at the PA board schematic. I may have missed it, but I saw no thermal protection hardware in the design.

There is a thermal sensor that reports back to the firmware and, I assume, back to the software. I don't know if either the firmware, middleware or software will act on that temperature data to limit or prevent RF output.

[Trucker]

There is a thermal sensor on the CM4 module. But, it isn't used. From what I have been able to find out, there isn't any thermal protection for the PA. And that is why the fan runs all the time.
James
WD5GWY

[w-u-2-o]

Just to clarify, there is both a CM4 thermal sensor (a standard Raspberry Pi feature), and a thermal sensor on the PA board. What the firm/middle/software does with that data is unknown.

You can definitely see what the CM4 temperature is using standard Linux tools, but that's not very helpful since it is amplifier final stage device temperature that is really of interest, of course.

[laurencebarker]

The RF board temp measurement, as far as I know, appears as a voltage on J22 pin 3 on the RF board. That connector goes to the rear panel I/O spreader board, and the TEMP signal is not tracked from there. So no, the firmware doesn't make any measurement of RF board temperature and has no way to cut off TX if it is over temp.

As noted the raspberry p temperature is measured by the pi itself. The FPGA die temperature is measured and reported in p2app startup; I don't imagine that is very useful information though!

[KC2QMA]

So based on the current design if you plan to use at the full 100w rf output for extended time always keep an eye on the PA temp and don't mod the internal fan to go slower

Well since there is sensor output on J22 then it is possible to create a variable temp controlled cooling fan MOD if one desires.