Very nice amp of incredible quality. Though only first class parts
(MP Capacitors only)
were implied not easy to use. Originally the amp uses EL12 tubes in triode connection
and a RGN 2504
mesh plate rectifier tube! Later the amps were equipped with F2a11
tubes. The small lamp is a level indicator!
The cathodyn driver stage is realized by the two EF12 tubes next to
the EL12s. So the
best way to use this amp for hifi is to feed the signal into the
input grid of the second EF12 tubes (the left tube in the row). The
grid is the center of the 3 pins.