Hi,
now I have done some tests with NYGM, too. I created a campaign.scr layer with only a single River-Class escort which should have the following radar devices:
LinkName=Type290
StartDate=19410101
EndDate=19420901
LinkName=Type271
StartDate=19420901
EndDate=19430301
LinkName=Type273
StartDate=19430301
EndDate=19430601
[Sensor 14]
NodeName=R01
LinkName=Type276
StartDate=19430601
EndDate=19440101
LinkName=Type268
StartDate=19440101
EndDate=19451231
The wavelength of the Type 290 was 1.4m; the Type 271...276 had a wavelength of 10cm and the Type 268 of 3.2cm. Metox could only detect wavelengths in the meter range.
In my test setup, however, Metox could detect all radar signals. This is in clear contrast to historical facts

As a consequence, Metox is much more useful in SH3 than it was in real life.
In order to correct this behavior, I will reduce the Metox' performance (or disable it) via SH Commander's date feature (from the time period on when the cm radar appeared).
Regards, LGN1