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Frequency Counter LS-223 ( Home brew )

[Outline] [Front view] [Top view] [Bottom view] [Block diagram]

[Pre-amplifire, pre-scaler and 10MHz clock osccilator]
[5V AVR pwb and capacitors for power supply]
[BCD to decimal converter (nixie tube driver)]

Fig.1 5V AVR pwb and capacitors for power supply

Fig.1 shows 5V AVR pwb. Under the pwb there are capacitors for power supply ( +5V and +180V ). Very old diode "SD-1" from old television set is used for +180V rectification and there is a danger sign " Kiken !!!" in japanese on the transformer.