Russian 6N1P-VI tube high-quality double triode. Low noise and microphonic effect. Optimised for "pulsed" mode of operation. Equivalent to the 6DJ8, ECC88, 6922
Russian 5C4S kenotron tube, direct-filament, two-anode. Designed for rectification of alternating voltage. Half 5C3S. Equivalent of the 5Z4, 5Z4G, GZ30, 5CG4, 6087
Russian 6N1P-VI tube high-quality double triode. Low noise and microphonic effect. Optimised for "pulsed" mode of operation. Equivalent to the 6DJ8, ECC88, 6922