K3 to SPE Expert 1K FA amplifier

From Zerobeat

To enable automatic band switching of the SPE Expert Amplifier from my K3, I made a screened cable with the following connections.

Line.....SPE Pins......K3 ACC Pins

A..............6.................13

B.............14..................3

C...............7..................9

D.............15................14

GND..........4..................5

The K3 CONFIG:KIO3 should be set to NOR, and the Band Switch setting on the amplifier to Yaesu .

The K3 TUNE facility is great. I have found that using just 5W I can get a reliable SWR indication on the amp to tune my balanced ATU, then switching to OPERATE gives about 250W without further adjustment. Setting the K3 PWR control to 12W gives around 400W. I don't use the ALC, besides which the K3 gives out the wrong polarity.

Stewart G3RXQ 17/04/2008