Sunday, 8 November 2015

GM Tubes



Some GM Tubes for a project I plan to build some time next year.

Sunday, 1 November 2015

A Posse of Transformers






























Nice little Ebay snip;  30 transformers for £12 - perfect for my kiln controller boards  ;-)

DC Voltage Calibrator






























This is something I bought from Ebay for £30.  It can output a voltage between 0.01uV to 9.9999v @30mA,   It contains a precision zener diode which is used as a reference input to a FET chopper amplifier operating in feedback stabilized mode.  The gain is determined by a set of precision metal film resistors which are selected by the 5 decade thumbwheel.







Looks like it was circa 1987.




The battery pack consists of 11 x 1.2 Volt AA Ni-Cads @ 700mA.  They were assembled in 1998 and they starting to leak.
































Because I didn't want to go to the trouble and expense to replace the batteries, so I just removed them from the unit instead.