Data just released below is for next model up in sophistication
ie for model Sbitx v1.01 =
IMPORTANT: Before powering on, it is vital to check the polarity of the power pin.
The provided DC jack should have the center pin connected to +ve and the outer barrel connected to the Ground.
There are three phono jacks on the front panel:
1. The left jack is for the microphone. The TIP is microphone, RING is PTT and the SLEEVE is GND. This arrangement allows you to use regular microphones.
2. The middle jack is for the earphones/headphones. The standard headphones or earphones that come with mobile phones should work.
3. The right side jack is for the key/keyer. The TIP is Dot, the RING is Dash and the SLEEVE is the Ground. You can also use the microphone¡¯s PTT as a straight key. The setting for the kind of key plugged in is described in the Operating CW Section.
Plug in the headphones into the middle jack on the front-panel. The standard Phone/PC handsets and headphones will work well. Choose a headphone that is comfortable for long hours of working. The demands on the headphones in a contest or weak signal work are very different from those of a HiFi music listening for pleasure.
The straight key should be plugged in to the right most jack on the front-panel. The wiring for the straight key is : (Tip : Key switch; Ring: Nothing; Sleeve: Ground) [Drawing]
You can switch to using an Iambic keyer. To do this, attach a keyboard and type: