I’m using not best quality 0805 inductors (it’s just too hard to buy good here in Batumi) from aliexpress so BPF loss and parameters are not the best. But it’s okay for my conditions for now, also I bought different non-smd inductors on the Aliexpress, will test…
BPF:
BPF — I’m wasn’t shooting start and stop freqs of the filters — it’s okay, so photos just to document losses 🙂
Final losses are result of sum of losses from 4 relays + PE4300 attenuator which has insertion losses 1.5db + 4 ADG switches (two ADG918 + two ADG904) 0.4db each + smd BPF filter + smd LPF filter. So in fact 7db is not so much for this configuration.
2m filter will be replaced with SAW filter soon, so picture just for info:
Commutation without BPF and LPF:
PGA103+ preamp with filters enabled:
70cm disabled:
70cm enabled:
2m disabled:
2m enabled — only 10db amplification 🙁 Need to receive SAW filter faster 🙂 — 20db is too much losses for filter in this config.:
20m HF disabled:
20m HF enabled — around 5db amp. this amp. is not for hm (as we can see — higher freq. higher amplification) But still some improvement to signal strength:
