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Comment by doug_life | Hacker News Reader

It is likely that that the sub had it's antenna tuned to work well in water while the RC car antenna was tuned for open air. The two different mediums will change the antenna impedance.

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Interesting does say shorter antenna, I could see that, I think the RC sub's antenna was like 4in long vs. an rc car's antenna that's usually like a foot

Yeah, my basic understanding of submarine communications is that lower frequencies penetrate the water better. Lower wavelength needs a longer antenna. The system US subs use is a very low frequency from what I understand.

> TACAMO (take charge and move out) is the back up communications system to the US nuclear submarine fleet in case an attack on land based transmitters disables them. A rotating fleet of Navy E6 jets equipped with 200 KW transmitters and two 2½-mile-long trailing wire antennas (TWA) at 35,000 ft altitude to provide 24/7 coverage. Short pings are transmitted every few seconds.

Regarding "longer antenna" for submarines... -- I recently learned about this signal from https://www.sigidwiki.com/ -- which has been helpful to ID all the fun stuff you can see with RTLSDR

Delicious, 2.5 mile long antennas behind airplanes

Corona, stuff like this, the sheer gall, it's impressive.

Sadly the 6000 mile antenna never got built, but they did get a few tens of mile long ones built.

https://en.wikipedia.org/wiki/Project_Sanguine

The cost of that must be insane - the price tag of being about the only military force on this rock capable of projecting force and delivering utter devastation 24/7/365 any place any time even if the entirety of the US got glassed.

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