Kali Linux - Fern: mon0 is not injecting or proximity is low?

[nigelmercier]

... I've got an ALFA AWUS036NH which uses the Ralink RT2870... The card is connecting OK to my test WEP AP, but when I run Fern (OK, I know, but I'm a noob) it reports: mon0 is not injecting or proximity is low despite being right next to the AP! ...

I repeat the above as this was an aside in my OP.

Any solutions?

[nigelmercier]

Really? No replies?