December 27, 2007
Ameritron AL-572 progress report
After four months of use it is time for an update
First of all, I don't agree with Ameritron shipping this amplifer out with the power supply generating a plate voltage of 3000 volts. The data sheet for the tubes clearly calls for a lower voltage. IMHO the excessive plate voltage is the primary reason this model has such a bad reputation for blowing up tubes.
The internal jumpers on mine have been changed so that the plate voltage is about 2400 volts. With the lower plate voltage, this unit can still produce 900 watts continuous on the lower bands, 700 watts on 10 and 15 meters, and generally manages over 1000 watts peak on single sideband.
On the plus side, the amplifier does exactly what is expected of a kilowatt class amplifier. Reaching out past 500 miles on 80 and 160 meters with marginal band conditions is not a problem. The amplifier also continues to function at a lesser power level with one or two tubes inoperative (more later) plus it helps keep the radio room warm on cold winter nights.
Last week the notorious MFJ lack of quality control finally struck. Turned on the amp one evening and noticed that it was only doing about 600 watts and two of the four tubes were dark. The cold solder joint was found and fixed easily but how many more have I not found yet?
Overall, I give it one thumb mostly up with qualifications. It does near legal limit power for SSB, it doesn't draw too much current from an ordinary 120VAC outlet, and it can continue to operate with 1 or 2 tubes out, if you are willing to deal with making modifications and repairs yourself.
Comments are disabled.
Post is locked.
First of all, I don't agree with Ameritron shipping this amplifer out with the power supply generating a plate voltage of 3000 volts. The data sheet for the tubes clearly calls for a lower voltage. IMHO the excessive plate voltage is the primary reason this model has such a bad reputation for blowing up tubes.
The internal jumpers on mine have been changed so that the plate voltage is about 2400 volts. With the lower plate voltage, this unit can still produce 900 watts continuous on the lower bands, 700 watts on 10 and 15 meters, and generally manages over 1000 watts peak on single sideband.
On the plus side, the amplifier does exactly what is expected of a kilowatt class amplifier. Reaching out past 500 miles on 80 and 160 meters with marginal band conditions is not a problem. The amplifier also continues to function at a lesser power level with one or two tubes inoperative (more later) plus it helps keep the radio room warm on cold winter nights.
Last week the notorious MFJ lack of quality control finally struck. Turned on the amp one evening and noticed that it was only doing about 600 watts and two of the four tubes were dark. The cold solder joint was found and fixed easily but how many more have I not found yet?
Overall, I give it one thumb mostly up with qualifications. It does near legal limit power for SSB, it doesn't draw too much current from an ordinary 120VAC outlet, and it can continue to operate with 1 or 2 tubes out, if you are willing to deal with making modifications and repairs yourself.
Posted by: ElChupacabra at
04:04 PM
| Comments (2)
| Add Comment
Post contains 292 words, total size 2 kb.
1
I am perpetually thought about this, thankyou for putting up.
Posted by: 411 reverse phone number at February 06, 2013 12:49 AM (WAKEr)
7kb generated in CPU 0.0049, elapsed 0.0274 seconds.
24 queries taking 0.0242 seconds, 29 records returned.
Powered by Minx 1.1.6c-pink.
24 queries taking 0.0242 seconds, 29 records returned.
Powered by Minx 1.1.6c-pink.