Mystery Crystal Set & Valve Amp

My Mystery Crystal Set, connected to a Battery Valve amplifier using a 1S5 & 3S4. Tuned across the AM band with about 10 metres of wire strung from the corner of the house to a tree as an aerial, and a meter of metal rod in the garden outside the window as an earth. The crystal set has two aerial connections, one for sharper tuning, the other for broader, but supposedly louder, tuning. The original Mystery Crystal Set design was published in the Brisbane Times in 1932. The 1S5/3S4 combination was used as the audio output of many battery portable radios from the mid 1950’s. A few construction notes on the crystal set are here, The amp details are here,