QRM Hunting / Messy Lab

So having got the bhi DIL DSP Receiver, the amount of QRM I was still getting wasn’t good. Although I was slightly tired, i really wanted to solve this issue.

I followed the DX Commanders Youtube posting on QRM here

So i then set about unplugging things around the house, the first thing I found was an electric blanket ! That put out a huge buzz, but there was still plenty of ‘noise’ amongst the signal. I turned everything off in my ‘lab’ and used a car battery to test –

Car battery, less buzzing…

So off a car battery there was a big reduction in noise, so it was something in the powersupply or surrouding room

At this point I used several of these magents and put on the power line in, HF and transformer

I set about winding, but still noise 🙁

By this time, i was still getting less, but still a big interference. I unplugged *eveything* from the transceiver and it stopped ! So it was something being plugged in.. I went thru each device, lo and behold the xggcomms CAT port was the main offender ! By this time it was getting late, and some much needed family time with a few brews and a good film was required to consider the next steps.

After the film and a nice walk of the dog at 11PM (to avoid other dogs/runners/etc) I cam in and started searching for ferrite cores, sure enough amazon had a huge variety, and on PRIME next day, so I ordered think, great i can get these Monday and get going ! Amazingly, even tho i ordered these at 11PM+, they was here the next day ! I was going to tidy the lab up, but set about attaching all the chokes I could to the cables between the mac and transceiver. The difference was amazing…

FT8 came alive very rapidly !

Within a course of an hour, i had made 9 QSO’s on FT8 on 40m, with 3 already confirmed on QRZ ! I was so happy that everything was working really well !

I think I am going to upgrade my chinese power supply which is meant to drive power-strip lighting, which is fine for VHF/UHF (A recommendation from FRED IN THE SHED on 27Mhz) but for HF I will get a decent 30~40 Amp campable linear PSU for the Kenwood to further reduce the QRM.

Now to stop playing on WSJT-X and tidy this place up !

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