SmartSDR Version 4.2 added User-Configurable Receive Filters, which allow the operator to customize a panel of 6 different receive filter buttons for each mode group. Whenever the slice is tuned to one of these modes, the Filter buttons for that mode group will be displayed in the Mode/Filter Pull-down menu.
The same buttons are displayed for the "Active Slice" in the "Radio Controls" Panel.
(NOTE: Access to this feature requires the upgraded "SmartSDR+" or "Early Access" Feature License.)
The Mode Groups are:
- SSB (USB/LSB)
- CW
- AM (AM/SAM/DFM)
- DIGITAL (DIGU/DIGL)
- RTTY
There are two ways to program the filter buttons:
(Either method will change the buttons displayed in the Slice Flag or in the "Radio Controls" Panel.)
NOTE: Changing a Filter's settings does not automatically apply the filter.
You must "click" on the filter button to use it after configuring it.
1) Direct Entry of the Filter's Parameters
- Right-click on the desired filter button and click on "EDIT" to open the button's configuration dialog box.
- Enter a 4-Character Name for the filter.
- Enter the low-frequency cut-off of the receive filter.
- Enter the high-frequency cut-off of the receive filter.
(If the boxes show RED borders, the filter combination is invalid)
- Click on "OK" to save the filter.
- Repeat for other filter buttons as needed.
2) Bulk Entry Using the Filter Programming Tables.
- Open the SmartSDR "Settings > Radio Setup > Filters" tab.
- Select, from the Mode Group pull-down, the Mode Group for the filters you wish to configure.
- Enter into the table the 4-character name and bandwidth parameters for each of the 6 receive filters you wish to configure.
(If the boxes show RED borders, the filter combination is invalid)
- Click on SAVE
- Select another mode group and repeat the procedure for each of the mode groups.
Below are some examples of mode group filters you can configure:
NOTE: Filters for CW, RTTY, & AM use filter numbers on each side of the signal center. For example:
- For CW: use -125 / +125 for a 250 Hz wide filter.
- For AM: use -3000 / +3000 for a 6 kHz wide filter.
Resetting The Filters:
If you are unsatisfied with the filter settings and wish to start over, you can reset all the filters in the mode group.
- Open the "Settings > Radio Setup > Filters" tab.
- Select the mode group for which you wish to reset the filters.
- Click on the small square box with the circular arrow.
- This will reset the filters in that mode group to their default settings.
- Now you can reconfigure the filters with all new settings.
Setting Global Filter Skirt sharpness and Filter Latency.
The "Filter Options" tab has three sliders that allow you to control the sharpness of the filter skirts from "Brick Wall" to gently sloped.
You can configure the filter sharpness in four different steps for each of the three modes:
- Voice Modes (USB/LSB/AM)
- CW
- Digital (DIGU/DIGL/RTTY)
Sharper filter skirts add a little more latency (delay) on the receive signal, but have a very sharp cut-off outside the filter passband. Setting the slider all the way to the right provides "Brick-Wall" filter skirts.
Softer filter skirts have lower latency, but the filter edges are not as sharp or selective.
The AUTO Button, when enabled, will automatically adjust the filter sharpness/latency balance depending upon the bandwidth of the filter in use.
When AUTO is disabled, the slider can be set to the desired sharpness/latency ratio.
How to Configure Filter Presets from Maestro or M-Model:
A) Open the Filter Presets Menu:
There are two ways to access the Filter Presets Menu from a Maestro or M-Model Front Panel:
- Touch the Slice Frequency to enter the Slice Menu.
- The six preset buttons are displayed on the bottom left hand side.
- Touch the Edit (pencil and paper) icon below the six filter buttons to open the Filter Preset Menu.
Or:
- Go to the "MENU > Filters" tab to open the Filter Preset Menu
B) Edit the Filters in groups in the Filter Presets Table:
- Select the desired MODE from the "Mode Group" Pull-down
- Tap and enter data in the "Name," "Low," and "High" boxes for each desired filter.
- Hit "SAVE"
- Move on to the next MODE and repeat the process.
- Tap "<Exit" when finished to return to the Panadapter.
Configuring your favorite receive filter bandwidths adds a lot of convenience and utility.
Enjoy the new filter access!