SPANFI by OK1DFC

Real first stage of SPANFI amplifier - 10/04/2007

New design with two band-pass filters, 144 and 432 MHz switched by OMRON signal relay.

Block diagram and schematic

 

Data sheet of AD8307

PCB board with amplifier and band pass filters
Amplifier, detector and programmable attenuator for 10 - 20 - 30 - 60 dB

AD 8307 detector

SPANFI including two ATT, one of them describe above, second one is for fine attenuation set up 1 - 2 - 4 - 8 - 16 - 32 - 64 dB

View to front panel.

View to rear panel.

Whole unit above 20/08/2007

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