Did the IJN have HF/DF?

[klh]

I tried a search on the forum, but didn't pick up a quick answer, so I apologize if this has already been asked.

Did the Japanese Navy have the equivalent of High Frequency Direction Finding or Huff-Duff? Is there any increase in risk when I send radio messages like in SH2 and SH3?

While I'm at it, am I right in assuming that the IJN did not pick up radar emissions like the US did to the Uboats?

[Bilge_Rat]

Japan had a very effective RDF network established troughout the empire. I dont think it's modeled in the game however.

[daft]

The Japanese did have a RDF-network set up in the Pacific and it was quite successful in tracking US ships even before the outbreak of the war. In the game there’s an increased chance of air attack if you’re heard by a Japanese RDF-station.