The acquisition of an attractive 1920/30 "Lissen" three waveband coil with integral switching was the inspiration for this little set. A use had to be found for the coil, but any set produced should be physically small. Also looking for a good home were several quality air spaced variable "condensers " that have been around for many years; probably WW2 vintage. There was also what I think was called a Muirhead Drive which looked nicely technical and was actually essential for accurate tuning. The spaghetti resistors (in grey)and grid leaks are a modern fudge and one of the capacitors has had open heart surgery. Modern terminal connectors on the back and a phone socket have been used for convenience, but in any case have changed little over the years. The final result is minimal circuitry,with three triodes resistance capacity coupled (PM1HF, PM1HL and 220P output).An aerial trimming capacitor was a necessity and the coupling to the aerial needs to be very light.The approximate ranges covered by the Lissen coil are :

	Bottom of scale	Top of scale
Lower range	5.6 mHz -(53 metres)	8.4 mHz - (35 metres)
Middle range	11.5 mHz- (26metres)	17.4 mHz-(17metres)
Upper range	22 mHz-(13.6metres)	30 mHz-(10metres)

The set is quite lively in the evenings; tuning involves the integrated use of all three variable capacitors.

Click here to return to Homepage		Click here to continue