Posts Tagged ‘MFJ 1788’

The MFJ 1788 is on the air and a contact in log!

Not the best shot but it's an evening shot
I was able to get the loop on the air today after work and I was very much wanting to see if it was actually working on the air.........testing it and putting it on the air can be a whole different kettle of fish. I am happy to say the antenna works just fine if not better. It seems to tune to a better SWR and seems more smooth at arriving at a low SWR. In the past it seemed to have a very sharp tuning curve and if you did not pay attention the sweet spot was gone. So the bands were decent sounding well were I was on 30m that is. I called CQ and I had a come back from VE3HEU! Not exactly DX but it's a contact and from what I have been reading the bands at times have been rough shape......HI HI. Vic was so close we could had met for coffee in the local Starbucks for goodness sake.  He is a fellow condo ham that was using a mobile whip antenna and at 10 floors up using approx 90 watts. I am not that bold and my power is at a steady 5 watts as I don't want to have a knock at my door. This gave me a great opportunity some CW practice and boy when you don't use it for some time you really  have to think about what you are sending. It felt really great to get on the radio again as it has been go go go  here with work, out of town guests and just plan old stuff around the house that has to be done. I think I may stick with 30m's as it seems to be very much alive in the early evenings.

Time to look inside the MFJ 1788

Taking a close look at things
It's the fall and time for some antenna maintenance for me there is no tower to climb or any outdoor work for that matter. It's as simple as bringing the MFJ 1788 indoors from my balcony and having a look. I have had the cover of the antenna off in the past so it was no problem to quickly remove it and start investigating. Some of the things I look for are poor solder joints, little critters who have made my antenna home, the smooth operation of the tuning capacitor and the over all health of the components.  It was a good thing I did check the mechanical connections and without exaggerating I have to say that almost all nuts were
Checking the cap fins
loose......some very alarmingly loose! The hardware holding the stepper motor in place was the worst but not far behind was the larger nuts that held the large tuning capacitor in place. I can't remember the antenna acting funky at all but I do believe it was just a matter of time before something reared it's ugly head like a quirky SWR! Another thing I like to do while the antenna is apart and fully cycle the tuning capacitor for not only smooth operation but the equal spacing of the moving fins along side the stationary fins. There was only some minor adjustments needed to the capacitor fins.........BUT where does "Murphy"  fit into this adventure........well just as I was finishing my adjustments the antenna slipped off the TV tables I had it on and the control wire that runs the motor broke off the circuit board! Also the "feed loop" wire was distorted somewhat. The feed loop is 10
Some of the many nuts that were very loose.
Control wire torn off.
gauge wire in the antenna that is contorted into a egg shape, this little baby can really play games with how the SWR outcome on the loop is determined. I played with it when I first got the loop and that was a mistake as it occupied about 2 hours of my time to get the antenna's SWR back to "normal". I vowed to never touch that feed loop again, but thanks to Murphy it seems I have to revisit that dark cave again. I re-soldered the stepper motor wires back in place and did my best with the feed loop wire. The antenna was put back together and with my fingers cross I tested it and to my utter surprise the unit was working better than it has in the past.

WHAT an SWR of 99:9!!

The other evening I had an opportunity to get on the air it has just been to long and I was very excited about spinning the dial around the HF band! I ran the coax out to my MFJ 1788 on the balcony and fired up the K3. I jumped on 20m were not to much was happening but on 30m there was some Dutch DX that was calling CQ so I thought I would give them a go. Prior to calling my SWR on the loop antenna was tuned to 1.2:1 BUT when I started to call the Dutch station my SWR readout on the K3 magically became 99.9:1!!! It was like the coax had been removed from the antenna and was sitting on the ground. It was late so I wanted to look into this at a later time, this evening was the later time so I hooked the antenna up and gave 20m a go and the SWR once again on the K3 was showing 99.9:1. It was time to trouble shoot, was it the coax, MFJ 1788 antenna, the K3 or my LDG antenna switch? The first thing I wanted to do was to remove the antenna as the problem.
Without LDG antenna switch
I removed the coax from the antenna and in it's place put a 50 ohm dummy load. In a way I was relieved to see the 99.9:1 SWR thus removing the MFJ 1788 from the problem. Next I bypassed the LDG antenna switch and low and behold the SWR now was 1.1:1 and me saying thank god it was not my K3! So it would seem the LDG  antenna switch is the problem so I took the switch cover off and looked around. I cleaned the SO-239 connectors, check the internal connections and all seemed to be great. The only problem spot to me could be the switching relays with internal contact troubles? After exercising the relays the trouble in the LDG antenna switch seemed to be ok. If the trouble comes back this is a 4 position switch and I only use 2 positions I could swap out relays and look at ordering all new relays. At this point all seems to be working well but stay tuned to see if relay swapping and ordering is in the near future.
Relay in the LDG antenna switch

VE3WDM is back into QRPp very low power contacts!

I was feeling under the weather this weekend and thought it would be nice and relaxing to spend some time on the radio. It so happens a CW contest was in full swing the Russian DX contest. I was not into competing but just handing out points. The propagation conditions this past week were a struggle to say the least. Today the conditions were on the rebound a K index of 2 and the Sunspots were in at 27 and the solar wind was still up at 615. I parked on 15m and there was lots of DX rolling in for the contest. I made only 7 contacts for Saturday (so far) most were done with QRPp power! I was very pleased that my condo antenna was able to get out to make some great QRPp low power contacts. My K3 is only able to get down as low at 100mW's silly me I sold my attenuator thinking my contacts under 100mW's were over! I was able to make 3 contacts at milli watt power, 2 contacts at 1 watt, one contact at 3 watts and finally 5 watts. My first QRPp contact in the contest was K5WA in the states, my next QRPp contact was with EA3CX in Spain. Then finally F5IN in France with 500mW's of power.
The 7 contacts break down as follows
1. F5IN          500mW          7,500 miles per watt
2. K5WA       100mW         13,213 miles per watt
3. EA5CX     100mW         39,956 miles per watt
4. DK3QZ     1 watt             3,818 miles per watt
5. DL0AO     1 watt             3,818 miles per watt
6. HC2SL      3 watts            
7. ZF2DX      5 watts

My QRP signal is spotted in Europe!

I had some down time over the weekend and felt it was time to spin the K3's VFO and see what was out there. I started on 15m it really did not seem all that busy but I was hearing some German stations so the band was open. My Elecraft P3 is great as I was able to get a snapshot of the CW portion of 15m. This allows me to not spend time moving up and down the band blindly and maybe just missing some stations as they end their transmission. One could end up concluding the band is dead and move on when in fact they just missed a station or stations calling CQ and waiting for a reply.  I ended up calling CQ in and around the QRP watering hole at 21.060, in the past I have checked the Reverse Beacon Network (or RBN)  just to see how my QRP signal was doing. At this new QTH
P3 on 20m showing some signals
for some reason I have been only able to get spotted in Canada and the U.S. To my surprise when I checked RBN I had been spotted in Hungary, Switzerland and Germany. I was very shocked and it kept me on the band calling CQ. Unfortunately there was no answers I then moved onto 17m and was spotted in France but again no answers to my CQ! I then ventured down to my standby band of 20m and found F5GPE Pierre calling CQ. His signal was in around 559 and I gave him a call and he came back to me with a report of 539. I did send him an email thanking him for the contact, he did get back to me giving me more details about his setup.

ARRL CW Contest done QRP style

Oliver is asking……"Ahhhh dinner!!!
I took part in the ARRL CW contest this weekend in a part time way, I was not able to go full tilt as I had things around the house that needed to be done. I skipped the Friday evening as it's most of the big guns going at record setting CW speeds. I operated QRP, single band, non assisted, single transmuter and with my MFJ 1788 magnetic loop antenna. The bands were alive with CW and you would never think we were in the downswing of a solar cycle! Then conditions over all were great on 15m I was able to get on from early morning into the early evening. In the morning the bands were filled with
The rig setup
Europe and as the late afternoon rolled around the South Pacific started to boom in along with Central and south America. Some of the standout locations I heard were Bangladesh, Guam, Japan, New Zealand and South Sudan. None of which I was able to contact the pileups were HUGE!! Some of the highlights for me were contacting Hawaii, Cuba,  and grabbing a new DXCC Dominican Republic.
Score rundown is as follows
Contacts        DXCC's      Points
81                   39                9360

The equipment  used was the Elecraft K3 with 500,400 and 250 inrad filters, the Elecraft P3, Begali Contour Key and the Flex control external VFO knob and last but not least the MFJ 1788 Magnetic loop antenna. The software used were N1MM+ contest software, N4PY rig control software and MRP40 CW code reader for the chain saw speed code. I never had Murphy pay me any visits during
The contest software
the contest which really is a first time. I found 15m to be a great band very low noise floor and lots of action. I did venture up to 20m for a listen and from my location it was very noisy and I was glad I decided to stick with 15m.  Sunday seemed to be an easier day for making contacts I had far less repeats to do, Saturday I really had to work for each and every contact. Looking forward to the next CW contest!

Monday brings two dx contacts

Monday was a stay in and stay warm day oh and also I was able to fit in some ham radio time as well. Next weekend is the ARRL CW DX contest weekend and since I had time on my hands I thought I would finally install N1MM+ on my PC. Up to this point I have been using the older version of N1MM, the only time for me to update was just before a contest. According to Murphy's law if you update your contest software just before a contest bad things will happen! N1MM+ has some nice new features all of which I have not tried as of yet. While I was setting up and getting to know N1MM+ I had my K3 on and was rolling around the 20m band. I was able to make 2 DX contacts the first one being IK3VUT from italy. He was calling CQ and he came back to me on my first call to him. This was not your typically fast contact Luca gave you a report but also shared his name, thanked me for answering his CQ and asked my name. It was not a long QSO but it was nice to not just have a 599 and move on Luca gave me an honest 559 signal report.
late afternoon it was time to go out with Julie who had a photography assignment that involved us going downtown (Toronto) for some shots she needed to get. It sure was cold out but soon we would be back to our warm home and just a little more radio time as she edited some photos. This time on 20m  I heard HC5AI calling CQ from Ecuador and after some going back and forth he got my call and the contact was made.

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