SDC Skimmer - Superb alternative to CW Skimmer

[Max]

Just a heads-up for those that did not know (I did not) that for any CW Ops on here, there is a superb alternative to CW Skimmer available. Seems may have been around some time but perhaps somewhat "under the radar" but it's rapidly making a name for itself judging by the fast pace of people signing up to the Google support group:

SDC SUPPORT GROUP
https://groups.google.com/g/sdc-ut4lw

It is called SDC Skimmer (somewhat cryptically the SDC stands for "Software Defined Connectors" but don't let that put you off) which is actually also a suite of programs related to CW/RTTY/PSK skimming and contest operation.

The full functionality of the suite (like the contesting features) is only realise with an TCI connection to the SDR software which SDRC does not offer. Nevertheless, it is perfectly usable as a CW Skimmer using just two of the modules (SKM Server and RigSync) to connect to SDRC and it works very well by utilising the CW Skimmer functionality already in place on SDRC.

SDC Skimmer has built-in com port connection suite (RigSync) so the use of Omnirig is not necessary. Two of us in the Test Team have set it up and got it going and it is very impressive indeed. For myself, I don't find it as crash-prone or resource hungry as CW Skimmer.

Here's another good reason to try it..... it is donation-ware whereas CW Skimmer is paid-for at $70 + 20% VAT for UK customers, presumably EU users also, so that makes it around $85 - not cheap.

SDC Skimmer is written and fully supported in a Google user group by Ukrainian Yuri UT4LW:

Yuri, UT4LW
https://www.qrz.com/db/UT4LW

One thing to note is that a registration code is required to trial SDC with SDRC as you need full IQ interface via VAC which is not offered in the free trial version. However, if you email Yuri he states that he can provide the Reg Code and he may be willing (I don't know this for sure) to do this without an initial donation to trial it if you explain you need this to make get a working trial with SDRC before deciding. But probably the most decent thing to do is donate as two of us have already proved it works very well with SDRC. The requested donation starts at $20 which is absurdly good value if you feel it's even fair to offer the minimum donation for such a spectacular piece of software, especially considering the comparison to CWS compulsory price.

For those that want to give it a go and get up and running very quickly, I have placed the setup screens from SDC, SDRC and VAC that work with SDRC on the link below as it looks a bit daunting at first. The PDF manual is 254 pages!

PDF MANUAL:
https://www.lw-sdc.com/wp-content/uploa ... /SDCen.pdf

If I have not shown a setup screen then it's all as per the default at installation. I've used the "Night Style" dark theme as I prefer the look (set in Setup tab of SDC where you can also disable/hide the unused modules for a clearer screen):

SETUP SCREENS
https://drive.google.com/drive/folders/ ... drive_link

Note that as for CW Skimmer you also need to set up a Virtual Com port pair (I recommend VSP Manager from K5FR as it always seems hassle-free) and also a Virtual Audio Cable as per Simon's instructions for CW Skimmer:

SDRC SKIMMER SETUP INC. VSP & VAC
https://www.sdr-radio.com/cw-skimmer

To get the full bandwidth of the SDC Decode from the IQ feed you will need to set sample rate of the VAC to 192kHz sample rate and also in SDRC CWS setup screen and the SDC software (see bottom of my pic setup screenshot SDC2 - Bandwidth). Remember this VAC must to be dedicated just to SDC Skimmer and is allocated in the SDRC CW Skimmer setup menu and also in SDC software. In my screens it is VAC Line 4.

On SDRC in order for it to tune the CW signal exactly correctly when you click on a callsign in the SDC Skimmer display, you must be in CW mode in SDRC. Edit the CW filters in SDRC to have a centre frequency of your preferred CW tone frequency for receiving. Then clicking callsign in SDC tunes SDRC to your perfect tone. For perfect match also set your sidetone frequency in SDRC to the same preferred frequency. Then everything syncs perfectly with no further inputs required.

Once SDC is running, in SDRC, tune to the frequency of interest (suggest centre of the CW section) and then just give one "touch" of the Zoom control in SDRC with "Auto-Centre" enabled to set SDRC radio LO frequency to be also centred at that point. For that point on, to tune a station you just click callsigns in the SDC Skimmer display to tune signals. Note the tuning is one way only, from Skimmer to SDRC. You can still tune SDRC manually, but it's intended to use it the other way around. This is the expected (and required) behaviour.

SDC sometimes needs the Skimmer section "Start" button to be cycled at the start of the session. You usually only need to do this once. If you don't see what you expect in the Skimmer display, toggle Start button off/on and also possibly give the Zoom control a quick touch In SDRC as described above to centre the SDRC radio LO and all should come good.

73

Max

[Max]

Forgot to mention that decoding capability is at least as good as CWS and perhaps even better:

https://www.youtube.com/watch?v=_gceAUupgg4

It is very impressive indeed. For myself, I also do not find it as crash-prone or resource hungry as CW Skimmer.

Max