This exhibit is a Fleming four-anode detector made for Marconi. It is difficult to see how the four anodes improved the signal detection over the basic diode.
The tension spring attached to the side support is present but the filament has failed. This image has been enhanced to bring-out the Marconis WT Co Ltd on the envelope.
The anode segments are stamped differently but look to be identical in form.
Here the final part of the Marconi identification has been enhanced. The number under the name line is 10.
all four anodes are the same length. The twisted wire supports attach to the to joined anodes - one either side.
Here the S hook at the base of the tension spring can be seen. Each anode is curved with a central support on the outside.
Another view of the symmetrically placed anodes.
The base pins are of simple split-pin construction. Each of the electrodes is labelled on the base cap.
More of the etched lettering.
A close-up of the top of the electrodes.
Here the thickness of the sheet nickel used for the anodes can be seen.
Diagram of the valve used to drive a relay. Probably this drove a pen recorder for the incoming Morse.
The balloon envelope is 78 mm in diameter and, excluding the base pins, is 144 mm tall.
