This is the preliminary node map for the scope
http://home.graffiti.net/diverse:graffiti.net/miniscope_node_map2.jpg
Scanner does not like full A4 useage.
Letters E, K and C along the top
2 tag boards running vertical, numbered from bottom S (16) and R (16) then P
(11) and Q (11),
colours match major component pinning numbers to node numbers.
ground lines not added and some components around the front panel pots,
switches and 2 3.5 mm i/p sockets (feintly marked as worn off , maybe read
INVERT and GAIN not readable on the earlier pics) not transcribed. Some
unplaced loose wires
and 2 caps covered in laquered cloth so left in place as unknown values and
puffy cap values are assumed , ignoring the green and yellow "multiplier"
dots that are probably temp or tolerance values.
polarised caps marked with a - .
QQ is unkown function as knob missing and other Q pot functions as letters
on the knobs, as found.
There are bound to be still more errors, I've just noticed the 22K resistor
apparently going to doubley N/C K6, maybe used as a tag.
M & VIB wiring and power select shorting plug arrangement is probably much
like the valvepage schematic including the vib, for the later miniscope.
Power cable wiring Y,R,B is the same in both cases
Next intermediary schematic is placing the valves etc into the optimum
coloured nodes and un-knotting to a certain extent.
Nothing powered up so far, a few volts from variac may resolve a few
problems, and valves not tested yet.
Primary of M is probably ok , selecting 230V is 129 ohm and 180V is 75 ohm
The socket for the vib is badly fixed , one bolt is skew as it interferes
with something else on the chassis. So maybe not original vib type but I
don't see how a synchronous type could have made it Si diode rectifierless.
What were the smallest Se rectifiers available in the 1940s for this sort of
application ?
page devoted to this project
http://home.graffiti.net/diverse:graffiti.net/miniscope.htm
