Mysterious movie - Japanese American family, a farm, an island and radio station on comb

I'm trying to find a movie that my friend watched as a teenager. The movie was set on a farm on an island off the coast of Washington state. A Japanese/American family hired a farm hand to work for them. The hand ended up having an affair with the farmer's wife. He entertained the 2 kids by doing such things as listening to a radio station on his comb. I believe this film came out around 1970. Whole family was Japanese American.

Any idea? There aren't:
Koya no toseinin (1968)
Dreams of Glass (1970)
The Migrants (1974)
Sutoroberi rodo (1991)
Snow Falling on Cedars (1999)

Thank you in advance. Every guess will be useful.