I have an old Regency ACU45A UHF 450-470 RF PA that appears to be modified with an additional PA board. The original 45W PA board is marked "Regency" and "604-143 Rev L", all the component part numbers are marked on the board as well. The additioal board appears to be of Regency/Wilson/Rhelm manufacture but has only 2 markings on it, "MC 3881" in ink and "604-149 F" in solder. This board has 5 ajustable air capacitors, a e/m relay, 2 Motoloa 9236 transisters along with afew other small components. The ACU45A is nominally a 45W PA, however the extra board kicks the output to over 100W. The PA is currently functional and tuned in the 440 band.
Can anyone provide me with any info or a schematic of this additional board ? Doug N3DAB
