Band switching is supported in Win7 and Win8.

LPT band encoder - BCD truth table

Band
A
B
C
D
position
50
0
0
0
0
0
144
1
0
0
0
1
222
0
1
0
0
2
432
1
1
0
0
3
903
0
0
1
0
4
1296
1
0
1
0
5
2304
0
1
1
0
6
3456
1
1
1
0
7
5760
0
0
0
1
8
10GHz
1
0
0
1
9
24GHz
0
1
0
1
10
47GHz
1
1
0
1
11
76GHz
0
0
1
1
12
BCD bits go high (5V) for the band activated.
Data bit A is the `Least Significant Bit` (LSB) and data bit D is the `Most Significant Bit` (MSB).

Decoder inputs are connected to LPT1 as follows:
A
LPT Pin 2
B
LPT Pin 7
C
LPT Pin 8
D
LPT Pin 9
Ground
LPT Pin 18

When CW is selected on LPT, connections are as follows:
Emitter Q1
LPT Pin 1
Base Q1, with 3K-ohm series resistor
LPT Pin 17
Collector Q1
Rig key jack
Rig CW ground
LPT Pin 18
Q1
2N4401

Important: Read this about hot-switching #4.

rev: 02/2016