1xCW /SSB 2.7K narrowband filter compatible with YF-122S For YAESU FT-817/857/897. - The identification circuit with the original filter can be inserted in the machine to identify what kind of filter, the filter may be generally of 1K 500,2.7 k displayed on the screen displayed on the screen of the filter 2.3, so only the screen than to display FIL1 FIL2 intuitive, of course, you can also let him display FIL1 FIL2.
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