Bert Modderman Engineer

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2320 2400MHz filter 100 euro

The filter shown far below on this page for 2320 to 2400mhz was to narrow and many customers where not happy with its bandpass.
So i decided to create a new one myself with 2 notch filters.
this filter has 0.75db loss max from 2330 to 2490 and 1db at 2320 and 2400. 2300 to 2320 also usable.
im actualy measuring lower loss i think. analyzer says 0.36db for 2360.
need to make a few more filters to find optimum but max loss will be 0.75db garantueed.
wifi supression above 2400mhz can be done in 2 ways. agressive or mild.
see graphs. the agressive wifi suppression setting starts falling down from 2390 and 2425 is almost 50db suppressed.
the mild setting makes the filter run to 2400mhz with 2425mhz 15db suppressed and 2450 approx 40db.

graph with the hard setting for wifi suppression. i doubt anyone needs this kind of suppression but show what the filter is capable off.

below has an integrated 2db scale graph that shows ripple of about 0.25db from 2330 to 2390.
markers are 2320 and 2400 and center 2360. (the 2 outside are 2425 and 2450)

Because the lower filter for 13cm with notches was realy hard to reproduce with good specs i decided
to redesign new 13cm filters.
the first attempt is this low loss, very broadband, duplex filter.
50db down at 1245, 60db down or more from 1260 and above.
downside, only 10db down at 2500 and 14db down at 2200, but 45db down at 2000

housing is only 9cm x 4cm and losses are around 0.3db to 0.5db from 2330mhz to 2390mhz
this filter is 100 euro and is only ideal for duplexing with 23cm and blocking 1800mhz signals.
if wifi is your problem then this is not your filter.
but is excellent for the dx-er and contester because of its very low loss and good attenuation of 23cm.

2018: an improved version of this is developped and is 100 euro, more details later