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2019-08-08

Station Grounding?



It was the Best of Times, it was the Worst of Times …



John VA7XB
With apologies to Charles Dickens, I will start by saying that the Radio Society of Great Britain’s BERU (British Empire) CW contest represents one of the “best of times” in my opinion – strictly for British Commonwealth countries and a new experience for me.  It’s Thursday and I’m getting prepared for the BERU a couple days ahead of time, so the first order of business is to get the new and improved N1MM+ Logger loaded up and configured.  I read the instructions carefully and all goes smoothly.  This software has many new features but has a similar look and feel to the old one, so the transition is quite easy.  Next thing is to bring up the BERU contest file and revise the macros so they fit for this contest.  Done, now let’s try it out.  Here’s where we get to the “worst of times” part.

Thursday evening and I see 7QAA (Malawi) on the cluster for 20m, so this is a good opportunity to give N1MM+ a pre-contest workout.  His signal is strong and he’s working split – let’s see if I can bust the pileup.  The amp is on and tuned so I point the beam to 46 deg and call him. I hit the F4 macro to send my callsign about 2 kHz up from his transmitting frequency.  

All goes as planned the first few times then suddenly everything freezes up.  Repeated pressing of the F4 key with the mouse has the same result – nothing is entered and nothing is sent.  Cripes, I’m glad he didn’t call me back for the exchange.  A few more tries but success appears random.  An hour or so of experimenting with various things makes no difference…there is a problem here and it’s going to have to be resolved before I can make headway.  After a while I give up trying to break the 7QAA pileup as nothing is going right for me, and call it a night.  I wonder if the problem has something to do with the new N1MM+ installation, so will plan to use N1MM Classic in the contest until I can get this sorted out.    

It is 8 am on Saturday and 20 m is starting to open to Europe.  As I turn the computer on, it emits some audible groans and immediately crashes.  On an attempted reboot, the PC automatically goes into “repair” mode and after 15 minutes grinding away, comes back to life, apparently OK after having completed a system restore in the process.  Back to the contest.   I’m on N1MM Classic now. Having succeeded in calling and being heard by a G3, I then hit F2 for the exchange.  Dang, the computer freezes up again.  So I try the mouse instead – same thing.  Then I try the CW paddle to make the exchange manually but it doesn’t respond either. What the heck is going on here?  By this time the G3 Headquarters station (bonus points!) has given up on me and I’m getting perturbed.  This fiasco continues spasmodically for some time until eventually I switch to 15 m.  Now things seem OK again and I log some good Qs.  And so it is with 10 m – no problems for the next couple of hours.  

Later in the day, I’m back to 20m and the gremlin returns.  So is the problem the hardware, the software, the computer or what?  And why only on 20 m? I check the settings on the Microham and N1MM, cable connections, reboot etc and these things all seem normal. It eventually occurs to me that maybe this is an RFI issue, as I’m running 750 watts and have made some cabling changes in recent weeks.  So I round up all the ferrite cores I can lay my hands on and lock them on the computer cables for another try.  This time, things start to hum so it looks like this may be the solution.  

Later in the day the high bands dry up and I decide to QRT for good, after 6 hours off and on.  Despite the frustrations I did log a few satisfying Qs to reduce my torment: VU3KPL and VU2PTT (India), ZS1EL (South Africa), 9J2BO (Zambia), V5/G3TXF (Namibia-2 bands), C5/M1KTA (the Gambia).  93 Qs in all – nothing to boast about and it could have been a lot better without the RFI. 

But, wait, it’s not over yet.  Now it’s a week later and time for the BARTG RTTY contest.  I turn on the system and quickly find the 20 m gremlin is still with me.  So Sheldon and I stick to 15 m for the first day.  Later I am thinking that maybe I have ground loops, as not all the critical gear is connected to a common ground.  I fix that and change out my keyboard as an extra measure of precaution.  A quick test shows that 20 m “seems” OK now, but the bands have dried up (a recent Coronal mass ejection) and there are no further contacts to be made.  So further testing will have to await another opportunity.

Hey, I just thought of something…the ground for my shack is about ¼ wavelength long at 20 m so would that be  affecting the equipment?  I’ll have to experiment with that.  Somehow I think the “worst of times” are not yet over.

~ John VA7XB




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