The ARX-2125 is a 125 watt power amplifier for 220 MHz. I have found little information about the amplifier except N2CKH page
http://www.n2ckh.com/125m_rptr.htm
The amplifier before modification
The following picture shows a modification with the first stage removed. This modification works well and 1 watt in gives 100 watts (2 watts = 140 watts) out at 28 volts. A couple of watts will product 75 watts @ 13.6 volts. In addition you can by bass the first strip and 30 watts will produce 100 watts @ 28 volts.
If you leave CA2832C first state in place, 40 mill watts yells 100 watt (60 mw = 125 w) out. The problem is it looks pretty bad to me on the spectrum analyzer. See last photo.
The source looks pretty good to me, It is about 40 MW coming from the exciter of a converted GE Mastr II. scan range is 200 MHz to 500 MHz
Same frequency range as above but with the bird showing 100 watts thought the amplifier. The specks for the CA2832C say Input/Output VSWR (f = 1–200 MHz) and I think that is causing the poor results seen on the spectrum analyzer.
