Laserbeam delights - Audio DSP filter for CW



Last Monday I had a bit of free time and I have been planning to help Keith G0RQQ put his new audio CW filter into a box for some time. It made sense to use the bench in the workshop here because everything is set up and read to go, Keith preferred that option to destroying the dining table at his place. He has a Laserbeam dual band filter module from Sotabeams http://www.sotabeams.co.uk/dual-bandwidth-filter-modules-ssb-cw/ and I have to say it is a great bit of kit for something so small. Well worth the money to add a new level to older or wider receivers.

In the classic QRP style Keith wanted to fit the board into an Altoids tin to be the ideal companion to his Frog sounds QRP single band 40m rig. Keith did add on the additional filter integration kit from Sotabeams for an additional £5.50.

VK3YE has done a great look at this and has a video demonstrating its use on home-brew kit. Have a look at the video to get a really good idea of how this works.



We really were blown away by the performance of this little box of tricks when we tried it on the big rigs in the shack. The filter is a brick wall when switching between wide and narrow and it is excellent to listen to. I think this filter may well be on the cards for me to pick one up very soon to play with the rigs here at M0TEF towers.





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