Hi Tom.
Thanks. Yes, i have the 2 V rms in mind. It was stated in the
datasheet. I intend to use a series configuration of 3 antiparallel
1N4148 diodes on the input to protect the filter. At 50 Ohm, the
leveles are hopefully below 2 V rms. Otherwise i will use a stepped
attenuator in series of course (if clipping occurs).
73, Stefan
Am 30.06.2012 11:23, schrieb DK1IS:
Am 29.06.2012 23:54, schrieb Stefan Schäfer:
MF,
It becomes better!
I just realised that this filter is perfect to protect a receiver like
the IC706 when using a BIG antenna as the MF receive antenna. It will
be easy to build a passive circuit out of a transformer 50 Ohm -> 18
kOhm -->Filter--> 18 kOhm -> 50 Ohm. This can be put in a
small box and then there will be no problems! I remember how the 706
and others behave on long wires, i.e. multi-band antennas...
73, Stefan
Hi Stefan,
using those filters in the antenna circuit of a rx keep in mind that
the maximum input voltage is rather limited due to the high internal Q
of the mechanical resonators. Here I have some 200-kHz-units from RFT
with maximum input voltage of 2V resp. -10 dB relative to what ever. So
be careful when using them with a seperat rx antenna!
73,
Tom, DK1IS
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