OPTIONS
IF FILTERS
Adding filters of different bandwidths will help you receive signals in a crowded signal
area. The smaller the bandwidth, the less a signal on an adjacent frequency can interfere with
your frequency of interest. Every type of signal has a certain bandwidth: usually 4 to 6 kHz for
broadcast, 3 kHz for SSB, and 150 Hz for CW. If you use a CW filter of 500 Hz to receive a
broadcast station with 6 kHz bandwidth you will be cutting off most of the signal - not a good
idea. A 1.8 kHz filter will work great in SSB mode because it is just wide enough to let one
signal through while filtering out adjacent signals. Adding filters will improve your ability to reject
adjacent interfering signals and pull in those weak ones.
The R-5000 will accept up to four filters of varying bandwidth. The filters are selected in
series, with the overall bandwidth being determined by the narrowest filter used. The front panel
SELECTIVITY switch gives the operator the choice of four bandwidths: N, M1, M2, W or AUTO.
In FM mode, the SELECTIVITY switch does not work, as the receiver has a fixed 12 kHz
bandwidth in FM mode.
FILTER TYPES
The narrowest filter must be installed in the N position, with M1, M2, and W holding
filters of increasing bandwidth. The N position is where a narrow CW filter like the 500 Hz
YK88C filter would be installed. There is also a 270 Hz CW filter, the YK88CN, for the CW
enthusiast. M2 is where the "stock" 2.4 kHz SSB filter (YK88S) is installed from the factory.
There is also a 1.8 kHz SSB filter, the YK88SN, for the SSB work. The W position is where the
"stock" AM filter is installed. This is a very poor quality filter, and the first thing you should do is
replace this filter with the 6 kHz AM filter YK88A1. There are also a couple of "custom" AM
filters with 4 kHz and 6 kHz bandwidths that offer better performance for DX.
In the AUTO position, the bandwidth is automatically selected by the receiver depending
upon the mode selected. The following chart shows how the bandwidth is selected according to
the mode:
SELECTIVITY MODE
W AM
M2 USB/LSB
N CW
N FSK
You'll notice that the M1 filter is not selected automatically, and can only be selected by the M1
position of the SELECTIVITY switch.
For a "full-up" shortwave broadcast selection, you can replace the stock AM filter with
the YK88A1 filter in W, a custom 4 kHz filter in M2, move the YK88S to M1, and the YK88C in
N. If SSB is your specialty, then try the YK88A1 in W, the YK88S in M2, the YK88SN in M1, and
the YK88C in N. Try the YK88A1 in W, the YK88S in M2, the YK88C in M1, and the YK88CN in
N for CW work.
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