NN4ZZ SDR-Bridge V3 & CwSkimmer V2 SETUP – A quick start guide
Revision History
1-Nov-2022 - Initial version for updates to support FLEX SSDR V3.x softwareThis guide is NOT for versions of SDR-Bridge prior to V3This guide is NOT for versions of Flex SSDR prior to V3.x
This guide is NOT for versions of CW Skimmer previous to V2.1

Table of Contents
 Version information for all programs – Page 3
 Download information for CW Skimmer – Page 4
 Download information and setup for SDR-Bridge – Page 5
 SmartSDR and DAX setup information – Pages 7
 Setup information for CW Skimmer – Pages 9
 Using SDR-Bridge – Page 12
 Troubleshooting notes – Pages 13

Document Overview
This updated guide is to the new version of SDR-Bridge that supports the SSDR
versions V3.x and later. It works with version 2.1 of CW Skimmer. The capabilitiesof each program are extensive, this document will not attempt to address all of them.
It is recommended that you start by getting just one instance of CW skimmer runningwith SDR-Bridge and then explore the possibilities and capabilities of each program.
The setup is not difficult but there are a number of minor things than can cause
problems. In addition to the recommended settings for each program, there is atroubleshooting section that can help if you run into difficulty.
Regards, Al / NN4ZZ - email: Al (at) nn4zz (dot) com

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Simplified data flow diagram

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Version information for CW Skimmer, SDR-Bridge, and Flex SSDR

 CW Skimmer – Version 2.1 or later SDR-Bridge – Version 3 or later SmartSDR - Version 3.x or later

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CwSkimmer

Down load and install the latest version of CwSkimmer into the default directory.

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SDR-Bridge
Down load and install SDR-Bridge from:http://www.qrv.com/sdrbridge.html

Ver 3 has a new feature for spots.

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Note: The Telnet port in CW Skimmer must match the port shown here. For example IQ1 is 7310. See the CW Skimmer
telnet port setup later in the document.
If you need to reset the values in this screen to the defaults, the process is described in the troubleshooting section.
Access this screen from the EDIT dropdown on the main scree.

Page | 6SmartSDR
Set the DAXIQ channel on the DAX dropdown on the left side of the SSDR screen.
Note: The DAX settings in the SLICE are not used for CW Skimmer, only the DAX IQ
setting on the left side of the SSDR screen is used.

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DAX control panel
The DAX V3 control panel should look like this:The only DAX setup needed for CW Skimmer is the IQ stream. Set the Sample
rate to 96000. Note about the FREQUENCY displayed in the DAX control panel.
It is the center frequency of the PANADAPTER, not the frequency of the slice
receiver.

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CW Skimmer Setup
Radio – SoftRock, Sampling 96KHZ, CW Pitch to match SmartSDRRADIO Tab

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Audio TAB – your DAX IQ device may be named slightly different.

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Network TAB

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Using SDR-Bridge
Start your testing by setting up just one CW Skimmer window.

Steps to set up a CW Skimmer window Select/Assign a SLICE Check the SKIM box to start up the window
NOTE: There are options on the Radio and Skimmer tabs that affect how the program
operates. There are options you can set by RIGHT clicking on the SLICE requency. To getstarted you can just use the defaults. Review the official SDR-Bridge doumentation to see
what works best for the way you operate.

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Troubleshooting notes:- Verify the versions of SDR-Bridge, CW Skimmer, and Flex SSDR. It is easy
to get an older copy loaded that will probably not work. It’s also easy tolaunch an older copy since you may have multiple versions on your PC.
- Don’t start up CW Skimmer from a shortcut. Let SDR-Bridge start up CWSkimmer when it starts. Otherwise you can have multiple copies and someconfusion.

- If there is no data being sent to CW Skimmer, check to be sure the DAX IQ
channel is set.

- Sometimes the CW Skimmer instance needs to be manually closed and reopened to start working. It may even be hard to close (give errors) and haveto be stopped with the task manager. Usually after closing the skimmer itwill start up normally from the check box in SDR-Bridge.
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- Win 10 users – it has been reported in one case SDR-Bridge and CWS wereworking fine but stopped transferring IQ data on just one of the IQ channels.
After much checking no cause was found but a PC reboot corrected the issue.
- If rebooting doesn’t fix the flaky channel problem, another option is to change
to another channel. For example if you are using DAXIQ1 then try 2 or 3.
You have to set that in 2 places.
o Select the DAXIQ channel in the SSDR screeno Activate the skimmer with the slice desired in the IQ option on theSDR-Bridge “Bridge” tab.
- If skimmer is up but not displaying the calls and other data, be sure to checkthe TELNET settings tab on CW Skimmer. Be sure they match the telnet
settings in SDR-Bridge. Also check program versions.

- If the SDR-Bridge settings are wrong, or get set wrong, you can reset them tothe defaults by doing the following. To restore default settings, delete thecontents of [user]\appdata\local\w2rf.
- If the skimmer frequency is slightly off from the slice receiver, check to see if
your CW Skimmer CW Pitch matches the pitch setting in SmartSDR. Be
aware that Skimmer currently may be off a bit due to the granularity forsynching.
- Sometime the Skimmer does not display the same frequency data as yourslice receiver. You can often re-synch them by shaking the slice receiver.
(click and hold in the panadapter and move side to side)

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- Sometime the Skimmer .ini file get corrupted by changing settings. If you
suspect this is the problem you can overwrite them with a fresh copy the Ed
provides. See the snapshot below to show where to get the fresh copy andwhere to paste it to overwrite the corrupted copy.
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If CW Skimmer is displaying but it looks bad, check to verify that the sample
rate in the DAX Control panel isn’t set to 48,000. It should be 96,000

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-If your CW Skimmer screen doesn’t show the call information or decoded text you may have accidently ENABLED
BLIND mode. You will see the frequency displayed, the code steam, and the “dots” but NO text.
BLIND MODE = ON

BLIND MODE = OFF

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- There are some new options for working split on SDR-Bridge starting in V1.1.1. If younotice some things like muting or TX Active working differently, take a look at the newoptions to see if you need to makes changes for your operating style.

The changes are on the BRIDGE tab and the RADIO tab.

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- When CW Skimmer starts up you get this continuously repeating error: Output sample
rate out of range.
Check the CW Skimmer Audio I/O Device on the Audio tab of the CW Skimmer settings.
It should NOT be set to the same device as listed in the Signal I/O Device. Typically it isset to your audio output device but you may have to try some other settings.

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- Several users of CW Skimmer have reported that the following error message appears
on program startup:"Access violation at address 00404DD3 in module CwSkimmer.exe. Read of address
00000000."

The error occurs only on those systems where the Skimmer was installed using a regularuser account on Windows, with standard privileges. The installer has to put some
executable files in the Program Files folder, and some data files in the user data folder.
Since the regular users are not allowed to write to Program Files, the installer runs asAdministrator. As a result, the data files are placed in the administrator’s data folder,
not in the user's folder. This is how MS designed their security system, and this cannot
be bypassed.
To fix the problem, log in as Administrator and copy the data files from admin's folder toyour user's folder. For example, if your admin name is AlexAdmin, and your regular username is AlexUser, then you copy all files from this directory
C:\Users\AlexAdmin\AppData\Roaming\Afreet\Reference
to this one:C:\Users\AlexUser\AppData\Roaming\Afreet\Reference

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Chuck / W9WLX reported this issue. All frequencies sync and follow--the slice
receiver, SDR Bridge and the TX frequency on CW Skimmer. If I set the TX frequency onskimmer to the center frequency of the DAX IQ stream, it works as expected. However,
if I change the slice frequency, off the center stream frequency, it shifts in the opposite
direction. For example, if my center stream frequency is 7.020 and I double click on astation at 7.022 on the Skimmer waterfall, the slice receiver will follow and go to 7.022,
however the station is really at 7.018.
The problem was the “left / right” channel was set up incorrectly in the CQ Skimmer
Audio panel. It should be set to I / Q.

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George / K3GBB reported the skimmer display was not showing the fullbandwidth shown on the SSDR screen. Note in the snapshot below signals
below 14.054 do not display on the skimmer screen.

The problem was the DAXIQ bandwidth setting in Windows. It shoud be
192000 hz and was set to a lower value. Open the Sound Control Panel.
For the active DAX IQ and RESERVED DAX IQ devices make sure BOTH
are set to 192khz.

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Problem – Skimmer shows some spots that looks like dupliates. This issue noted by Ed / W2RF -- This problem

happens when users have DAX IQ channels that are covering out of band frequencies. This happens mostoften with 192khz, but can happen with others if the center of the panadapter is near the band edge. The Flex
produces very weak images outside the band, especially in WIDE mode. However CW Skimmer is sensitive
enough to pick them up. So you get out of band spots, that look like duplicates of an in band spot. (So thesymptom looks a lot like a wrong sample rate setting, but it isn’t.)
There are several things you can do to avoid this.
1 - One is to have calls verified by the master dta file, but it only contains the calls of contesters.
2 - Another helpful thing is to make sure the noise blanker is on. It’s the first blue icon on the option bar. (Ialso always make sure the key click filter, the second blue icon, is on.)3 - But the best solution is to select a band plan and tell it to only skim in band:

Finally, since there is some tailoring of the INI file, once they get everything the way they want it users mightfind it useful to back them up from Program Data/W2RF.

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