Allied Radio "Knight KM15" Monoblock Amplifier - RT's Radio Home Page

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Allied Radio "Knight KM15" Monoblock Amplifier

Amateur Radio > Micellaneous Tube Projects

The Knight KM15 is apparently a single channel, 12 Watt hi-fi audio amplifier. The seller found this at an estate sale along with other tube type and amateur radio equipment that the family was throwing away. He saved it! Here is a photo as I found it. The cover is missing. :-(

Sadly, it had suffered damage in storage; two of the tubes had been bent over in their sockets which cracked the envelopes; note the gray remnant of the getter deposits at the tops of the two tubes. Closer inspection revealed they are genuine Mullard tubes made in England.

Judging from the soldering methods, this was obviously a "Knight Kit" as these were popular in the 1960's. One capacitor disconnected from it's soldered location while I was checking its value! All of the paper and electrolytic capacitors will be replaced as will several resistors which have drifted more than their ten percent tolerance.

This capacitor grew nearly 1/4 inch during the few minutes testing.

All paper capactors have been replaced. A 6BW4 rectifier and two Russian replacement 6BQ5's were installed. It sounds good. Still looking for a pair of genuine 6BQ5's.