[RTTY] Yaesu FT-920 setup - HELP!!

[John Fleming]

> To repeat a previous message, I've had no problems with two - no, make
> that three - different types of regular non-Darlington opto-isolators
> keying the PTT, CW and FSK inputs of an MP. It would be very surprising
> if the 920 required different levels, since all that generation of Yaesu
> HF rigs are re-using a lot of the same circuit technology.

Ian, what "regular" optos did you use?  I've heard of some successes, but
not with the 4N-series, e.g. the 4N25.