Yes, TramDr literally put the gloves on when playing with this little 3 tuber. You ask why would I do that when I don't even put the gloves on for the big boys? Well, this amp is transformerless. Takes all voltages straight off the AC mains. No transformer step up or down, no isolation at all. It runs the HV (High Voltage) off a Quadrupuler circuit, the filament and LV (Low Voltage) are in series of the mains. Three 30v filament tubes in series, and a couple 10 watt resistors in series for 20V to run the low voltage. This is a Tetrode amp with voltage on the screens for much higher gain and swing than a grounded grid amp. The screen voltage is tapped at near the center of the quadrupuler. The quadrupler also is not grounded, as the -bias is tapped at the - side of this quadrupler. Fan runs right off the mains. Other than the transformerless design and tetrode mode, everything else is pretty standard. Decent preamp with a separate preamp relay. standard auto rf sniffing keying circuit, with a good sized rf changeover relay. Has a relative out meter and SSB delay cap. 4 stage RF determined by the screen voltage. Especially in Low power, a swinging monster. The 3 tubes are all outputs, don't need a driver tube in Tetrode mode. I like it, but I'm too chicken to mess with it much with that transformerless design.
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