Tuesday, March 22, 2011
Making of a 211 amplifier, Part 2: Assembly
The plate already comes with all holes for the screws which are needed for mounting the parts and to fix the plate later in a wooden frame. In the photo, speaker terminals, RCA and mains inputs, fuse holder and switches (on/off and ground lift) are already attached to the plate.
First the capacitors get mounted:
As can be seen, the B+ power transformer and also the output transformer are already mounted as well.
The next two photos show the top side of the plate:
The output transformer needed to be mounted sideways, otherwise it would not fit under the transformer cover. A frame construction was necessary to firmly hold the OPT.
The sockets of the 6HS5 driver and 6CG3 rectifier tubes are not directly attachedto the metal plate. They are a bit recessed below the plate. This is to have larger creepage and clearing distances from these sockets to any metal parts. The high voltage present on some of the pins makes this necessary.
The last photo shows the amp completely assembled and wired, ready to be tested:
Part 3 of this series of articles will show the completed mono amps in their wooden frames and describe the testing and first listening.