Finally, more than 100 watts!!!
I've been building a new station at our new house, pretty much from the ground up. Having wanted one for a long time, I took the plunge and added a linear amplifier. There are countless reviews out there on the various amplifiers. For me, it came down to bang-for-the-buck and the Ameritron AL-80B was the winner. There are other amps that have more features. There are other amps that require no tuning and automatically switch everything (solid state). There are other amps that make more power. But when you stack everything up, you just can't go wrong with either the Ameritron 811 (including the "H" model) or the Ameritron AL-80B.
I chose the AL-80B for a couple of reasons:
Although the AL-80B can be directly connected to the ICOM 756ProIII, I chose to go with an interface relay. I'm building the opto isolator from KK5DR. But until it's built, I'm just going with a direct connection. It's working fine right now, but for the long-term I'm looking to isolate the two devices.
Having never owned an amp, going through the tuning process was somewhat straight forward. The manual is a little confusing when it comes to ALC adjustment. But a little searching on the internet and comparing that with the owners manual, here's my normal tuning procedure:
The part I've left out of this is the ALC adjustment. Use the steps in the owners manual.
I'm currently running the AL-80B on 110V electric service but I can tell it's not enough. Or maybe I'm just seeing higher than normal voltage drop to the receptacle. I'm going to switch it over to 240V this week and expect that to make a huge difference from everything I've read. More on that when it's done.
Okay, the 240V conversion is done. Well, I'm actually running it at 250V right now but will probably change it back to 245V. The service voltage is fluctuating a lot here so I'm going to watch it over the next couple of days. But the change is already noticeable. I'm seeing much less voltage drop when keying the amp. Although I'm having trouble getting it up to a 1KW, it's solid in the 700W range. But then, it could just be me and how I'm tuning. But it's definatly working.
Another update... I'm running at 245V on the taps and made some additional ALC adjustments. I'm now getting 900W+ when driven with full output from my rig. I generally run around 600W which is much easier on the tube.
Final update... Since moving to the Elecraft K-Line (K3, P3, KPA500) I find myself seldom using this amp. So, it's been sold to another HAM that will use it more regularly.