It's good you've got some power out of the amp now. Based on the numbers above you should be seeing approximately 300 watts out of the amp now. That's a lot better than no output and no current rise above bias levels like you saw a while back. The next question is whether the rig is actually driving normal power into the amp or is perhaps folding back its output power when driving the amp. Sure check the cables as recommended in previous posts but bad cables would more likely be related to no power at all from the amp as you were previously seeing. I'd temporarily put a power meter in line between the rig and the amplifier. You're checking for two things, does the rig put out normal power when the amp is in line and active, and if not is the SWR between the rig and amp high? You can use your new tuner for these measurements, just make sure the tuner is in bypass mode so you're only using the metering sections and not trying to tune the amp's input circuitry. The most common causes of low power out of an amp (that is reflected both in low plate current and as low RF output power) are: - Insufficient drive power from the rig which could be caused by the rig folding back its output power in response to high SWR looking into the amp's input stage - Some problem in the amp's input stage including dirty relay contacts or mistuned input circuitry which could lead to the problem above - Or bad amplifying tube(s) in the amp. So start by making sure the rig's output power doesn't drop when the amp is keyed. IOW, test output power with the amp connected but in standby mode and then test again with the amp in active mode and keyed. The rig's output power should stay the same when the amp is keyed.