My MFJ Auto-tuner
Some years back, I purchased a MFJ 994 Auto-tuner. I needed something that would handle the higher power of my solid state amplifier, just recently purchased. When it arrived, I installed it in-line between the amplifier and the antenna. It worked great, just as I hoped it would and continued to do so for several years. Nothing lasts forever though, does it? One day while transmitting with the amplifier on, the tuner started to re-tune automatically. This is a no-no when transmitting at high power. A tune cycle should always be done at a lower power level to avoid arcing the relays and burning the contacts. I was able to resolve that situation and after doing another tune cycle, it appeared I was back in business. That turned out to be false hope. Within a few days, the tuner would no longer do the job I had purchased it for. What do you do? The tuner was no longer under warranty. Should I send it back for repair or was it even worthwhile to do so? Undecided on what to do next, it sat for a couple of years under my ham bench until one day I decided to contact MFJ to see about repairing it. Either I would have it repaired or I would buy another. To be truthful, I did not feel super satisfied. For what I had spent, I felt the tuner should have operated for a much longer time than it did. Of course there is always a question regarding the failure. Was it a fault related to the tuner or simply bad luck. I have always had decent performance from any of the MFJ equipment I owned so had no particular reservations about buying MFJ, at least not until now. Finally, I made the decision to return it to the factory. This was following a call to MFJ where I learned that their rates for repairs was quite reasonable. So off the well packaged thing went and I did not happen to be in a huge hurry for it; after all I had been without it by then for at least a couple of years. Then, summer came and we packed up our holiday trailer with intentions of spending a couple of months in Alberta. Both the wife and I have siblings there as well as our youngest son and family live there. Guess what arrived, about the time we were ready to leave. The unopened box got shoved inside the door and sat on the floor for the next two months as we made a good holiday out of our time in our neighbouring Province. I’m sure you know how it goes when you return from a vacation like that. Busy busy busy! There are always a million things that need to be done so during our return somehow the box with the tuner got set on a shelf and forgotten. As it turned out, it would be several months before I remembered it and opened the package. The first thing I checked was to see if I had actually gotten my own device back. That was easy. I had scratched my call sign into the metal case on the back side. I’m not sure how much it would have mattered to me had it not been the one I sent in for repair but as it happens, this one appeared to be mine. Delighted to be able to use the tuner again and the amplifier, I hooked it up and gave it a try. Imagine my dismay to find that it was not working. I tried it with several antennas in several situations, all with the same results. Disgusted, I removed it from the signal chain and threw it into the corner while I pondered my options. I could send it back but to do so would cost me shipping to the factory and the return. And I would still have no guarantee that it was going to work. The tuner sat for a couple more years, out of sight and out of mind for the most part. One day I decided to give it one more shot before I threw it away. I hated to just toss it. I had paid plenty to have it repaired and since so much time transpired between its return and to date I hardly thought that MFJ would look at it without charging me and when I added up the current costs as well as projected costs, even if it did get fixed, I had spent more than I would have done had I simply bought a new tuner. A sad situation. I connected it once again to my radio stuff. The same result as before. No tune! One reason for my reluctance to dispose of it was because the relays had all been replaced, according to the work order. This time I decided to check on the internet to see if others had experienced the same failures I seemed to be getting. Somewhere in the mess of results from my search I ran across one ham who discussed doing a factory reset. Hmm. Now, I happened to be aware that it is possible to do that. The question was, in my attempts to use the tuner, had I ever done that? I could not recall that I had, so I proceeded with a full factory reset. Eureka! The dang thing worked, and not only was it working, but exactly as it should. Who would have thought? Delighted with that result I switched from the internal tuner in my Icom radio to that one. The internal tuner, while being very convenient, simply does not have the tuning range of the MFJ and thus it never would tune my antenna on the 80m band. For the sake of convenience I would happily use the auto tuner. I join with a number of ham friends each afternoon for a half hour of rag-chewing. That afternoon I joined the “net” only to find that there was a horrendous noise being generated right on the frequency that we were using. That noise was so bad, I had to ask the guys to shift down band by several kilohertz else I could not copy the lighter stations. This was a noise I had not experienced previously. At the end of our “net”, I switched the tuner off, before shutting the radio off. To my amazement, the noise also disappeared. Some quick troubleshooting revealed that the culprit had to be the “Walwart” I was using to power the tuner. That particular “Walwart” is getting tossed. Now, I can report, all is working as it should be.
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If you bother to look at the date attached to some of these posts, I can tell you the date does not always reflect any addition or deletions --- Just saying --As I sometimes add to existing comments to update the subject. It is true that I do not often bother to add to the blog but from time to time, and especially now, during the Covid 19 pandemic I am able to find the time and inclination to create more content. Step up to the Icom 7610
The Icom 7300 did not last me too long. Within a couple of years I opted to step up to the IC-7610 radio. The 7610 shares many features with the 7300 but offers so much more. There are two receivers in the 7610 as opposed to a single receiver in the 7300. That is a feature that many may not feel they need however when band conitions are not so great having two identical receivers can be huge. The IC-7610 allows the user to connect two seperate antennas as well as a third receive only antenna. In use, one antenna can be connected to one receiver and the other antenna to the other receiver. This allows the operator to use a feature called diversity receive. The advantage to diversity receive becomes obvious when antenna one is (let's say) a vertical antenna and the other (antenna two) happens to be a horizontal antenna. This is where the magic happens. With a single receiver with, of course, a single antenna you are at the mercy of the current band conditions. The target signal's strength can vary greatly and there may be times when it fades into oblivion. Well good luck with that. If you are using diversity receive then receiver 1 is syncronized to receiver 2 and surprise, the signal becomes stronger on receiver 2 while it fades away on receiver 1. Icom has it set up so you can pipe the audio from the left speaker to the left ear while the audio from the the alternate receiver will be sent to the other ear. The beauty of all this is that you, the operator will not lose contact with the other station. How cool is that? Of course there are many other additional features to induce one to buy the 7610 as opposed to the 7300. I do not regret for a single moment having purchased the 7610 and I sold the 7300, not needing it any more. The location where we live in Colwood has, over the past decade, become an extremely unfriendly to radio, environment. Which is to say that the local radio frequency noise has gone from the delightful low noise environment to one where the local interference is almost enough to cause one to leave Amateur radio and pursue another hobby. The following is an article I wrote that covers some of the things I have done to enable me to still enjoy this hobby and lifestyle. (coming) A Low Noise Receiving Antenna
Three weeks ago, I spent the money and purchased a Wellbrook loop antenna. They seem to be extremely pricey but, maybe not so much, as I am finding out. Here, at my location in Colwood BC, I have been using an inverted L as my main antenna, backed up by a 43 foot vertical for the higher bands. Both antennas have worked well for me but with band conditions the way they are, my biggest problems have been to hear incoming signals rather than to worry about being heard by other stations. Now, when I moved to this location, it felt like I was in Ham operators heaven. All power lines in my area are underground and there was so little noise, this location seemed to be the holy grail for ham radio. Fast forward to the year 2020 and that is no longer the case. If I listen on my inverted L antenna, the noise is so strong that it registers a solid S-9 most every night. That means, any signal I want to hear clearly must exceed that strength or it is lost in the hash of the interference. No fun, believe me! I tried all the usual stuff in an endeavor to find the source of that interference and eventually was able to diminish the strength of the noise by 2 S-units. Not great, but nevertheless huge in terms of being able to copy desired signals. As we shifted into summer, I again noted a steady increase in the ambient noise until it finally reached the level where it had previously been. Talk about a bummer. What do you do? I started researching ways to address that issue. One of the solutions that kept coming up was to use an active loop as a receiving antenna and to transmit on my inverted L. Obviously no amount of noise was going to have much effect on my transmitted signal so all I had to do was solve the receiving issue. If I could, all would be golden. Right? Enter the MLA_30+, a receiving loop from China. I found dozens of reviews of this antenna on Youtube. Based on those reviews, I purchased one through Amazon.ca, knowing that if I had any issues with it, Amazon would back me up. At $65 for that loop, I would say it looks to be overpriced once you get the package but after it had been connected and working I had to admit, it did make a massive improvement over having to listen on the Inverted L. My listening enjoyment had just jumped up a notch. The usual S-9 noise level on 80 meters was reduced to S-5 or thereabouts. Then it rained. The loop quit working. This came as a total surprise to me since the electronics seemed to be well packaged even to the point where the loop amplifier is encased in epoxy. That was a head scratcher. However, the following day the loop was back in business. Who knew why, but it was working, so I proceeded to make multiple comparisons between it and other antennas. After a couple of hours of use, the antenna became intermittent and then ceased functioning altogether. This time it did not come back and no amount of cajoling could get it to work. Ahh! Now my dilemma was to continue with the far less costly antenna, in other words, buy another and hope it would work for a longer period of time or explore alternatives. I knew there were several other companies that were selling active receiving loops but all of them were much more costly than the Chinese made loop. Being the naturally cheap Ham op, I opted to try building a receiving loop with a pre-amp purchased from Amazon. Sadly that too turned out to be a failure. Performance lacked what I hoped for quite dramatically. Finally I decided to spend the money and buy one of the Wellbrook loops from Great Britain. I had it in my head that their loop amplifier was the best. Four hundred or so dollars later, I found my Wellbrook loop on my doorstep. You might think I would have rushed to get it assembled and tested but that did not happen for the next few days as I had other projects to finish. Finally I managed to get around to it and connected it to my SDR receiver. It worked, though initially I had some doubts, it was so quiet. Yes I could tell it was working but the question remained, how well? The dreaded band noise, when listening on the loop was ever so much lower. This I found encouraging and determined to find the optimal location in my yard to set the antenna. I eventually settled on a spot away from the house and other interference generating locations. Now, when I listened on the 80 meter band, the signal meter in my radio indicated a noise floor of around 2 S-units. Could it actually be correct. Had I really managed to drop the received noise from S-9 down to S-2? I had to test it out on some “known” signals at a time when I could compare it to another of my antennas. I pieced together the items I needed to connect to my Icom 7300. It is equipped with an accessory that allows me to receive on one antenna while having the ability to transmit on a alternate antenna. It seemed like nothing short of a miracle when I switched the transceiver on and saw the S meter hovering between 1 and 2 S-units of noise while noting that the signals I was listening to were bouncing to a strength of 7, 8 or even as much as S-9. I describe it as unbelievable! Fantastic! Worth every penny! Time has shown me that a received signal will be down by about 2 - 3 S-units (12 – 18 db) on the loop as opposed to listening on the inverted L. But, and it’s a huge but, I can hear a signal that only shows up at 2 - 3, S-units on the strength meter whereas I would never have known that station was even there before getting this loop. Since then, I have managed to get the MLA-30 working, with a larger diameter, more substantial loop as well as increased gain and I have to say it does a respectable job, however when compared to the Wellbrook loop, it is no contest. On 80 Meters, the MLA-30 receives with a noise floor of S4 – S4.5 whereas the Wellbrook loop shows a constant noise floor of slightly under S-2. That suggests to me that the MLA-30 is a reasonable antenna for anyone's needs but the Wellbrook loop is just that much better and when it comes down to which will I listen with, it is definitely going to be the Wellbrook loop. Is anyone looking for a slightly used, enhanced version of the MLA-30? (Just kidding – I’ll be keeping it too) You can never have too many antennas! Update! I have now used my receiving loops for roughly 2 months. In that time I have learned that my original opinion of the loops and how well they perform is not precisely how I had presented it. At the time I wrote the article, I had no way to connect the Chinese MLA-30 to my Icom radio. What I had done was to connect it to my SDRplay receiver while I connected the Wellbrook loop to the Icom. I was able to tune both the Icom’s receiver and the SDRplay to the same frequency and that made it easy to make a comparison. My bad! As it happens, I simply assumed that the Icom receiver’s S-meter would read similar to the SDRplay’s receiver or at least close enough to give me some valid results. Not so. Since that time I have had the opportunity to purchase the necessary adapters to allow me to connect both the MLA-30 and the Wellbrook loop to the Icom. (SDRplay uses sma type connectors and the Wellbrook loop uses BNC type connectors). Now I can do a comparison that is much closer to being fair. It was to my surprise to find that the MLA-30 compared much better to the Wellbrook loop than I had figured it to do, based on my earlier experience. When I see a noise floor of s-2 to s-3 while using the Wellbrook loop, I now see only 1 s-unit of difference between the two antennas. And when I observe the noise floor on the SDR displays, I see that confirmed visually. This tells me that the MLA-30, while not quite up to the Wellbrook loop's performance is certainly not significantly poorer. Considering that the Wellbrook loop cost me $400 and the MLA-30 cost me $65 dollars, I feel that cost to performance, the MLA-30 is a good choice. But! I have a friend that has switched to the MLA-30 as a receive antenna who does not achieve the same results as I do. True, he does see a reduction in local noise but not to the degree that I do. He has the same radio and presumably the same antenna but he is located in an older part of town where the houses are situated much closer to each other. I use the word presumably because there are two different models of this loop, the MLA-30 and the MLA-30+. I have the plus. I do not know which one he has. I know that some of the noise I receive is of my own creation but with the ability to park the loops away from my house, and with the results I get, I am simply not inclined to bother to track it down and spend a lot of time trying to eliminate that noise. As the saying goes “Your mileage may vary”. Added Dec 4 2020: The above article regarding the two loops simply details my observations regarding the use of these loops for the purpose of reducing the noise floor on various ham bands at my location. I will not recommend one loop over the other. It is my belief, whether right or wrong that the Wellbrook loop does perform better than the inexpensive MLA-30+ loop, which I believe is made in China. The question here, is, when you factor in the higher cost of the Wellbrook loop, does it perform sufficiently better to justify the additional expense? The Wellbrook loop cost me over $400 Canadian whereas the MLA-30+ cost me around $65 Canadian. Would I have paid the extra money for the Wellbrook loop if the MLA-30+ had performed properly from the beginning? I seriously doubt it. However, I must point out that I have replaced the stainless steel wire included with the MLA-30+ with a larger loop from 3/8" copper tube as well as fiddled with the gain adjustment that is internal to the amplifier. I recall reading somewhere that the larger loop would provide less of a null than the smaller one. A fact which may be of importance to some though not so much to me. The larger diameter copper loop should provide more gain as a receiving antenna, a fact that I cannot confirm since I have adjusted the amplifier gain which makes it impossible for me to qualify. To suggest I was not impressed with the stainless wire loop included would be an understatement. Well, doggone-it I didn't manage to get that Magnetic loop going in time for field day. I had a 5 rpm motor on order to use for remote tuning but it did not arrive in time. In fact it has still not made an appearance so what can you do? I elected to go with a ZS6BKW antenna (I believe that is the name) which is somewhat along the lines of the G5RV but supposedly offers better SWR figures on the bands. I can't verify that but it does work well enough. Made fewer contacts this year due to really crappy conditions but on the plus side, most of them were Morse contacts and that nets double points for the Morse contact. We operated two station radios and with quite good success and we operated about 19 hours out of the 24 available. Old guys need their sleep -- heh heh. Anyway it was fun and most likely I'll be back for field next year with the crew.
About time I revisited this site and updated it. I haven't time today to do much with it but I'll add something here. This is my latest project. I am building a magnetic loop antenna to use for field day exercise. We will be operating from the Seniors center down at Juan de Fuca parks and Rec and we will have a wire antenna up but want to try this alongside the wire. The plan is to do some CW contacts as well as phone contacts and I'll use this antenna and my own radio on the higher frequencies while the other guys'll use the larger antenna, with higher power, on the lower frequencies. I'm not satisfied with the capacitor I have there so am building one to use with this loop. This antenna should cover from 20 meters up through 15 meters when done. At least that's my hope.
Wow. I didn't realize it had been so long since I had made a post on here but I was reminded by an old friend that my blog had not been updated since August. Sadly he was correct. On the other hand I have been occupied with many other things and I guess posting just didn't seem all that important and true to the old saying, "out of sight , out of mind" I managed to completely forget that I had a blog.
Anyway, we are into our winter here in Victoria and have been having plenty of rain. I emptied the rain gauge on Sunday and here today (Wed.) I see we have 90 mm so far this week. If the rain keeps hammering us as it has we could double that by the time (next Sunday) that I dump it again. I may even have to empty it prior to that to keep it from overflowing. Sheesh! All busy around here and making plans for the summer already with Ev's pending retirement being a major factor in those plans as well as a few modifications to the old homestead. We are thinking of installing a double patio door in the dining room and possibly 1 or 2 of those Sun tunnels throughout the house. We have one already and are pleased with it. I may have a go at doing the installation myself. Even an old guy needs stuff to do. Been playing at getting an Internet radio working to use in the bedroom. I have a NAS (network attached storage) configured as well as a webserver all using a Raspberry Pi computer. Small cheap and actually pretty capable, this little computer can be had for about $60 and it runs the Linux operating system. Quite a learning experience for me. Thankfully I have a son that is an engineer and one who is very conversant with Linux. Hopefully he won't get too tired of his dad calling on him for assistance. Square dancing is keeping us in shape around here and that usually occupies three evenings a week and could be as many as six if we had the inclination and energy. I have had to slow down a tad with my guitar playing. The arthritis in my hand is really cramping my style there. I took a slug of meds today so I could go jam and they made me so nauseous that I didn't go. Can't win sometimes. Well possibly I'll be back with a post or two early in the new year. Happy holiday season to anyone who reads this. My friend Dave, the other active member from the JDF seniors center and I are planning a fall project which entails building a couple of magnetic loop antennas. In this particular case I plan to do some extensive experimenting and possibly deviate from the typical magnetic loop antenna. First though, I have some vacation plans and then we or at least my end of it will move ahead with the project. So nothing happening today but down the road. Weather here has been way hot. Those of us who reside on Vancouver island simply aren't used to the temps we have been getting or the drought we are experiencing. We have had 2.5 mm of rain from May through to mid July and then a one day shower that dropped 10 mm. Beyond that there has been zilch here at my location as far as precipitation. Hamming has taken a rather low profile recently due to poor radio conditions.
Just been gearing up for the upcoming ARRL field day exercises. We'll be doing our part from the Juan de Fuca seniors center and operating under the seniors station call which is Ve7srx. Information regarding just what that is can be found here. I figure it might be easier and more effective to provide the link to the site rather than me trying to explain. In a nutshell, Field day is an exercise that is designed to get radio operators up to speed on providing emergency communications under simulated emergency conditions.
This is a 24 hour event however it's my thoughts that we'll not likely operate for the full 24 hours. I am more interested in getting a temporary installation set up and working with decent antennas and proving that it works than I am in racking up a record number of contacts but one does tend to get carried away sometimes and generally the whole event is good fun as well as good practice. I spent today checking out the gear I intend to bring along as well as checking out the various software items that will be useful to aid in the event. Tomorrow I need to dig out my cot and sleeping bag although the weather is supposed to be hot so I can't imagine the need for a sleeping bag as such, perhaps just a sheet or so and a good pillow. Wow! Time does rush by. Here it is June 17th already and 2 weeks since the last entry in this blog. Not that I have anything important to add at any time.
And of course, very little of what I have done is radio related. I did add a longer whip onto the screwdriver antenna that I have mounted on the rear of the fifth wheel but when we went out on our next excursion to Coombs, BC. for June 12, 13,14th, somebody neglected to bring along a microphone for the radio and of course no Morse key either so I really didn't get to try the antenna or the radio. I simply gave up in disgust and packed the equipment away for the weekend. There scarcely seemed any point in hooking it up just to listen if I could not talk. Now, as for the weekend in Coombs, we had a great time. Friday night we square danced to the music of the Port Albernie Fiddlers, then Saturday we spent the day in Parksville visiting with some folk we've known for years and finished the day with 3 hours of dancing in the evening. The planned Sunday morning dancing was cut short just after it commenced by some motorist who decided to park his (or her) vehicle in the precise spot occupied by a power pole and with no music and no P. A. system it's really hard to conduct a square dance so the weekend finished a tad earlier than previously planned and all guests and holiday trailers were gone by 1:00 pm. Well. Here we are with May gone and now already the 4th of June. What a great month May turned out to be. Weather was awesome for the most part and we had a terrific time up in Campbell River at the square dance jamboree. From Campbell River we slipped over to Gold River to visit with my friend Bob (Ve7yo) and enjoyed the day and the visit very much also. It's always a kind of let down when one has to return to home and the everyday mundane things we do on a daily basis.
Got to try out the mobile antenna which I had mounted on the rear of the holiday trailer and with only 5 watts I was able to communicate with my friends in Alberta. I might have tried to make contact with my friends at home here on the island but times didn't work well for that so missed every opportunity to try that. Ah well. Next time perhaps. I need to update a few things electronics wise and then hopefully I'll be able to operate portable with a tad more power than the meager 5 watts I was limited to on this trip. I ordered a voltage converter from Amazon.ca to assist with that but I see it comes from China so it'll be a month or so before I get to try it out. We have another square dance weekend coming up and looking forward to that every bit as much as the last one. We need all the dance time we can get for later this summer when we travel to dance with some old friends that we have not seen in years. What can I say, it's good to be back square dancing. |
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