Posts Tagged ‘MFJ 1788’

A Friday evening nets some DX contacts.

On Friday evening I was able to pull some radio time out of my hat and it was time to try my MFJ 1788 loop antenna on 17m. I was very happy with the results it was very easy to tune (SWR of 1.2.1) and the band width was decent so retuning was not needed most of the time. I operate QRP at 5 watts so having the antenna on the balcony, it also being a small loop antenna plus QRP it's a bonus when I contact some DX.  I first heard S59AA calling CQ at 18.078 and my first attempt was not heard and another station jumped in and made his contact. I threw my call in again and I was heard and given a 559 signal report.  Franc was located in Slovenia and was operating an Elecraft K3 he was also booming in. The time was 5pm local time and 17m seemed to be wide open to Europe so I decided to spin the dial and see what else the ham god's brought my way. I then made contact with HB9CVQ in Switzerland, again another bonus for my ham setup. I was given another 559 RST but again I am just fine with that. I emailed both S59AA and HB9CVQ to give them a  little more details of my station but most of all to thank them for sticking with me and passing along a 559 signal report. I did hear back from Andy HB9CVQ who passed along some info about his station as well and it too included an Elecraft K3 radio . I try to avoid using the spotting clusters as for this tiny station hopping over to a busy spot just does not end well. I did spin the dial for a final time and I came across KH2L in Guam! In the past I had tried to make contact with Edward as he booms into here and I was not able too. Friday was no different I dropped my call but it was not heard by KH2L.....oh well. It's now Saturday afternoon and the bands are in so so condition I ended up spending time writing this post with the radio cans on.

Sunday evening on the radio

This weekend brought great weather and so it was out and about with Julie, but I did find some time for radio on Sunday evening. The bands were busy with contests and not wanting to get involved with them I skipped up to the QRP watering hole on 20m. I started calling CQ as I could not hear to much action. In a very short time W5TM came back to me and I was only 449 but it was a contact and that was good enough for me! Our QSO did not last to long as I was very much in and out I did send Edwin an email thanking him for the QSO. During my next CQ calling a G station came back to me but they were down in the mud. I switch on the APF and we did try over and over again to make contact but things just did not work out. It was pretty cool that my QRP signal was somewhat making it into "G" land. My last contact for the evening was with KA5KMS and this was a long QSO with a solid contact at both ends. Terry was running a Ten Tec Century 21at 25 watts into a dipole.  It was a good evening on the radio! They all were short QSO's but it will help keep me in the hobby, keep my code up and help me become more and more aquatinted with my rig. I have found that I can easily get lost in my ham programs, antenna issues and PC hiccups that involve radio. Bottom line it's great to put all that to the side and get on the radio and make some good old contacts.

SWR up’s and down’s

LP-100 reading
I was on the air the other day using the MFJ loop and as I was trying to tune to the lowest SWR reading I noticed an odd thing happening! Available to me at the station are 3 separate points to view the SWR. I have the SWR reading on the K3, the LP-100 and the MFJ remote control for the loop antenna. While tuning the loop antenna I was able to get an SWR of 1.5.1 on 20m with the K3's meter this is a very decent reading. I had the same reading on the MFJ remote unit but the LP-100 was showing 2.08 SWR??? The way the meters read the SWR are as follows.....the K3 right at the radio, then the LP-100 and then the MFJ remote unit. Oh and in case you are wondering if I am SWR meter crazy, I have the LP-100 in the game plan as it also reads very accurate output power and when operating QRPp it comes in very handy. . as for the MFJ remote that just comes with the antenna package and is really used to adjust the antenna and I really don't rely on it's SWR meter. I have heard and read in the past that the remote MFJ meter should not be relied on to much. ANYWAY.............I am getting this odd reading on the LP-100 and it is on all bands that I get a differing reading from the other SWR meters. First thing that came to mind was faulty coax or faulty
K3 meter
LP-100. I bypassed the LP-100 ( I removed the LP-100 and attached the two PL-259 using a SO-259 coupling) using all the same coax that fed the LP-100 and there was no problem. I then setup the LP-100 on it's own, meaning out the K3 through the LP-100 into a dummy load and there was a perfect match. Then I simply removed the SO-259 coupling and added the LP-100 again....there was the funny SWR again. Not sure what is going on here. In my trouble shooting I tried the LP-100 on it's own into a dummy load and it worked fine. I then used all the same coax cables and bypassing the LP- 100 and all was fine. Therefore LP-100 is fine and cables are good??? Not sure what is going on here.

Water + PL-259 = no radio for the day!

The waterlogged  PL-259
Well FINALLY I was able to get some radio time it has been so long and really there were no good reasons just what I call excuses!  On Saturday afternoon it was time to get some long over due radio time in. I ran my coax jumper  to the 1788 MFJ loop from my K3 radio, I settled into my radio chair and flipped the switch…..and……it was time for Murphy to visit me! With the MFJ loop you are supposed to tune the loop for peak noise and this was just not happening. I was getting numerous peaks but the SWR was all over the place! I thought about it for some time and after trying numerous ideas it finally hit me! I have a 6 foot coax tail on the loop and via a coupling I connect the coax from indoors. It was really raining the last few days and the balcony was very wet and "normally" my outdoor coax tail is in a plastic zip lock bag. This past rain storm was also accompanied with a strong wind and somehow the coax was removed from the bag and was in the water. I removed the coax and checked it with my ohm meter and it showed a high resistance between the centre conductor and shield. So it seems water has made it's way into the PL-259 connector and after installing a new piece of coax and doing some check with great results it was time for bed. My loop is supported by the MFJ tripod. I have a cover over the loop it to help disguise it and kinda makes it look like patio furniture. There is lots of wind being high up and on the lake so the cover has to be secured around the centre pole of the tripod. It's great that the antenna works perfect with a cover and with it secured as well I just want to come up with an easy way to connect and disconnect the coax from the antenna. I don't want to remove the cover or un-secure it from the centre pole. Any ideas from ham world would be approbated.
A shot of the balcony antenna open for suggestions. 

You never know until you submit.

Boy was I surprised to get this!
It was February 2013 and we just really finished unpacking all our boxes from the move into our new condo and I felt it was time to let some steam off and get on the radio. My new MFJ 1788 loop antenna had arrived and after some tweaking it was setup and ready to go. The ARRL DX CW contest was on and what a better way to give the antenna a workout! I blogged about my ARRL event and the use of the magnetic loop antenna. I was very pleased to see I was getting out and able to be a points giver in the contest. I was more concerned with checking out the MFJ's antennas performance from my condo location than taking the contest seriously. As a wise ham had told me long ago "always submit your contest score" and I did just that......last week a certificate came in the mail. It seems I was first place in Ontario south section for QRP!! No it's not top in the  country or world but for my condo station it was a great accomplishment. To think I was not even trying for an award.....maybe next year I will go for points and see how I do?

A good day on 17m

We had another cold snap hit us here with a wind chill in around -20C  it was time for some indoor radio activities. For some reason I settled in on 17m not a band that I frequent all that often, not sure why but never seem to stay long on this band. When looking at the P3 band scope the band did not look very active but as I slowly scanned across the band I came across some stations calling CQ. The first station was ZB2FK on Gibralter. There was not much of a pileup at the time when I made contact and I did receive a 559 from him and with 5 watts from an MFJ 1788 loop antenna I was very pleased with that contact. I then came across IW1DFU calling CQ again on 17m and I gave him a call he did come back to me but I had to repeat my call but again he gave me a pleasing 559 report. I then came across KH2L in Guam and he was in and out with the noise floor but I was very happy the loop was even picking him up! It was time to put the filtering of the K3 to use. I dropped the filter to 250 hz and added the Audio Peak filtering feature and that
Add caption
was all it took to bring him off the noise floor and into plan old CW. There really was no pileup to speak of but some where in line before me and I wanted to wait my turn. The propagation was such that his signal was up around S5 and then just at the noise floor. This is the exciting type of DX I like to try to work, it's a challenge and it could be hit or miss. It is very unusual for me to even hear signals from this part of the world but today at times he is S5. When given the opportunity I dropped my call and hoped for the best. Have you ever had this happen.......I for sure thought he was coming back to me and it happen to be the one time he was in the noise floor but maybe I was not at his end but at a possible S5. So I came back to him..........but it was not to be it was if the static was playing head games with me and coding VE3WDMmmmmm. To make a long
story short one of his contacts had spotted him on a cluster and then all hell broke loose!! My time was up as a HUGE pile started. I'm not saying QRP stations have not busted pileups but time was moving on and dinner was soon going to be on the table. KH2L maybe next time, I am not at all disappointed as these types of events help sharpen your skills and really allows you to become familiar with your radio. 

Final repairs on MFJ loop

Time to repair the control box.
It seems that almost all the bugs have been ironed out with the MFJ 1788 loop antenna. I sure have had an adventure with the unit but things seem to be on the upswing now. Some of the indicators the MFJ loop gives you when your match is good are High noise level meaning you are in the ball park. The SWR meters on the control box that visually tell you the SWR is good. Finally there is a tone that comes from within the control box when you are auto tuning the loop. As far as I am concerned this tone is only within the range of our cat Oliver's hearing. UNTIL........one day when I was tuning the loop in auto mode and all was going well until Julie tapped me on the headphones saying "can you not hear that ANNOYING sound!! I took my headphones off and still nothing it was not until I put my ear right up to the MFJ control box could I hear the tone. WOW my hearing must be way off  as Julie said it was very noticeable to her in the living room and to add insult to injury she also heard it over the TV. Needless to say this event happened a few more times and
Ready to remove switch
it seemed apparent that it was time to cut the wires to this speaker. While I was in there I also had to replace a switch that controls the range of the watt meter on the MFJ control head. The original switch did not work very well at all and MFJ was kind enough to send me 3 extra ones. Cutting the wires to the speaker (I could never hear) was very fast and easy but for this switch to be changed most of the unit would have to be taken apart it seemed. Once I was ready to remove the old switch and replace it with the new one it was very easy........having said "easy" it means that with the right tools it was easy. I used the Hakko 808 de-soldering gun and believe me this unit makes very easy work of removing the old solder. To the point were the defective switch just falls out of the board. In the past I have used the hand held de-soldering pumps and the wicks as well but nothing works as well as this unit. The solder station I have is the Weller WES 51 and it has served me well for many years and you can change out the tips for various jobs you want to do. So with the wires cut to the speaker and the new switch installed it's now time to just operate and no more (I hope) fooling around with the antenna.
A great tool to have


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