Ameritron ALS600, ALS606, ALS1300, ALS1306 Field Failure Correction

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  • Опубликовано: 10 дек 2024

Комментарии • 70

  • @JBanek
    @JBanek Год назад +2

    OMG!
    I've been doing Alien Autopsies on failed high power SMPSs for decades. You are to be commended for a such a great job. Ameritron, OTOH, should be condemned! Hand soldered boards, tons of "No Clean" flux, no QC or QA, etc.. FOD was usually behind 90% of IGBT failures I've found. The white goop in open jars collect all sorts of junk. Sometimes even the bristles of the acid brush. FWIW the goop should be applied with a roller to get a thin uniform layer.
    Overall you've done an excellent job diagnosing and repair. Your concern for doing a good job shows in your work

  • @larryw8er979
    @larryw8er979 3 года назад +6

    Thanks Tom. Your video really shows what you have been saying for a while. It difficult to translate a verbal description however to what is obvious in your video. It's hard to believe that any manufacturer could get away with that kind of workmanship and survive!

    • @Jerrythenerdful
      @Jerrythenerdful  3 года назад +8

      Perhaps this will prompt them to change manufacturing techniques. They have all the resources to be a really good company. They just need to pay attention to assembly and service quality. Let's hope they do!

  • @fernandoares9032
    @fernandoares9032 3 года назад +2

    Thank-you Tom for your explanation on why the FETS blow up. I wished I had watched it before my amp quit. I am glad I sent it to you because I am sure you will correct the heat sink problem. As many other hams stated, it is hard to believe that the heat comes in that condition from the factory. Car companies make recalls MFJ should do the same!

  • @craigraper2911
    @craigraper2911 3 года назад +3

    I am just glad mine has already been in to your facility and been checked out. Thanks again for the great job and being so informative when I came to pick it up.

  • @DavidMaihofer
    @DavidMaihofer 3 года назад

    Tom, seems to be a severe quality control with many manufacturers. My first job out of the Navy was with Sperry Flight Systems, Phx. We repaired assembly line F15/F16 digital flight computers and all rework was ordered back through assembly and QA. My second job post Navy was with Ford Aerospace and Communications, Houston, NASA MCC, telemetry pre processing systems. All engineers and technicians were diligently trained in soldering, wire wrap and termi point, as we breadboarded proto-types and did our own repair of FACC/NASA gear. Where this basic philosophy of quality control has gone is a good question to ask as no end user should have to go to these extremes to maintain their own gear. I value the video, as a matter of fact all of your videos as you take the time to walk through each and every quality related issue and make it clear. Very good at any level, for any operator. Thanks!

  • @Organplayer1947
    @Organplayer1947 2 года назад +1

    You are amazingly kind and generous in sharing your experience. I am now assessing the failure of my ALS1306 to power up. The 240VAC is good. Primary rear fuses are good. The amp simply shut down as i was tuning at reduced power drive, and the amp failed to power up. I suspect a blown fuse in the 50VDC input to the AMP power boards. I don't know of any other internal fuses. But your video has provided wonderful insights and I will assess ALL the areas you mentioned! Thank you so very much!
    Dave WA6PBJ

    • @Jerrythenerdful
      @Jerrythenerdful  2 года назад +1

      There are no user serviceable internal fuses in the power supply, other than one in the primary as a fail safe. You either have power supply module problems or bad FET's. We consistently find low pass filters out of alignment, wrong parts, poor soldering, loose hardware, and bad parts. If the supplies try to come up but kick back off, you likely have a bad FET.
      If the supplies are just dead, then you most likely have a bad 12V module.
      Of course it can be other things.
      One thing for certain, if you only change a bad part it will fail again.

  • @r1derbike
    @r1derbike 3 года назад +1

    Holy Toledo, Batman! Totally flummoxed here. I will wait 'til I have more 'disposable cash' and select a different brand amp that isn't assembled by Simian DNA recipients. There is no excuse for these assembly issues. Some look introduced post-production during repairs elsewhere but this should scare anyone away. Thank you, Tom!
    There is a descriptive moniker for a manufacturer/assembler who lets atrocities like this out the back door for consumption. It needs not to be said. It is understood.

  • @carlfrisky5158
    @carlfrisky5158 3 года назад +5

    It would be nice to have a video on fixing the noisy ALS-1306 fans that run on high speed all the time and a replacement source for the junk power switch that arcs when switched off.

    • @Jerrythenerdful
      @Jerrythenerdful  3 года назад +2

      They have had that information for years at the factory. There are four resistors involved in controlling fan voltage. The fan is a closed loop control system, but the gain and slope of fan voltage has to be matched to the particular fan they are using. The heatsink temperature determines fan voltage. The fan speed for a given dissipation and ambient determines heatsink temperature.
      The fans can be set for a crawl at room temperature, they will be dead quiet. As soon as the heatsink is up around 120-140F (depending on planned duty cycle) you want the fans full on.
      This amplifier has perfectly matched fans for heat sink area. It is just a matter of changing four resistors, two for each PA module, to get the room temperature slow speed and the speed slope with temperature increase.
      The power switch issue is because they changed to some cheap import switch that has poor snap action. A good rocker switch will snap from position to position no matter how customers push the switch. You have to "fight" a good switch into limbo between off and on and make it arc. A cheap switch has to be snapped with a sharp motion by the operator, otherwise it arcs. If I had the cheap switches when I designed this amp, I would have buffered them with a relay or TRIAC. Then a $.50 switch could have been used just by adding a $2.00 relay or TRIAC, instead of buying a $2 switch. Who would have known the switch would change? :)

  • @rickwilliams3084
    @rickwilliams3084 3 года назад

    Thanks Tom! I have recently acquired an ALS-1300 and it looks like a tear-down and cleanup of the heat sinks is in my future. Great video! 73, VE7TK

  • @jamesidone9482
    @jamesidone9482 3 года назад +1

    This video is great Tom, it shows why back in 2015 I had issues with my 1300, never over 1Kw but one day I turned it on and nothing, back to the factory and 4 transistors later it was back on the shelf, then it happened again this time it was the 4 tranies on the other side of the amp, fixed again but this time when I got it back I sold it and picked up a tube amp. It was a great amp when working, a little more fan noise then an AL1500 I had back a few years bit not like my first AL1200 you sold me way back when Ameritron was not owned by MFJ. ITs a shame they cannot build and QC an excellent product that you designed plus ole Martin charges way too much money these days and the QC is like the stuff he built in the eighties. I would like a 1306 but until they start building them right no thank you. I also never wondered why they placed the remote jacks on the front panels of the ALS600?

    • @Jerrythenerdful
      @Jerrythenerdful  11 месяцев назад

      The low pass filter changes they made and the remote system is a joke. Not only that, the construction is terrible. I have no idea who did that remote board, but it is really a strange system.
      They also screwed up the relay system in the AL80B, AL800s, and AL572. Fortunately, that is fixable with a few small parts.

  • @krazytrinisteve
    @krazytrinisteve 7 месяцев назад

    Gosh, you are a great orator and teacher. Just a tinkerer and I have seen the ameritron issues in my own stuff but great descriptive video.

  • @EXTIQUE
    @EXTIQUE 2 года назад +1

    I'm at a loss for words. i remember when Ameritron was TOP NOTCH quality built amplifiers. so much for me getting a 1306. looks like an AL-82 for me.

  • @bruceperkins1821
    @bruceperkins1821 2 года назад +1

    Excellent information, thank you Tom!

  • @MattyMozzor
    @MattyMozzor 3 года назад +1

    Hi Tom. Thank you for this video. I purchased a used 600 less than a year ago and it ran well for many months. While sending CQ on SST on 20m with only about 100 watts out of the amp, there was a pop and smoke came out of somewhere. I immediately stop the tx and powered down. When I let things cool off, I powered up again and now get max of 300 watts output with a noticeable hum in that I think is coming form the linear power supply. After watching this video, I am now have the courage to try and trouble shoot the problem . My guess is I fried to output transistors, but I am not convinced there isn't also something wrong in the power supply. I will let you know what I find. Thanks again and 73 Matty wb2jcc

    • @Jerrythenerdful
      @Jerrythenerdful  3 года назад

      The early ALS600's had a copper spreader and a thinner heatsink. There always was a problem processing the copper. The machine shop wanted to punch the metal, but that flares the copper and makes a tiny ridge. It has to be drilled and then countersunk slightly at holes. I've found several of them that were punched, and then to remove the ridges someone sanded the surface on a belt sander.
      This of course makes scratches that prevent good thermal contact. I've successfully blocked them off and got rid of most of the scratches.
      You just have to see what yours looks like under the FET's.
      Reducing power does not reduce dissipation as much as we might think. Heat actually increases with reduced drive until it crosses a peak at about half power, then it starts to drop again. Even at 100W there can be a lot of dissipation. The nice thing about the analog supply is you can run less voltage when you reduce power by using the RTTY position. That greatly.improves things.
      I tried to get a high/low voltage switch put in the switching supply. For some reason that just never happened. It would make a huge different in heat at reduced power.

    • @MattyMozzor
      @MattyMozzor 3 года назад

      @@Jerrythenerdful I did not realize that the reducing power does not reduce heat until I looked at some of your graphs on your other pages. I am a physicist and measure outputs and such of x-ray generating equipment and should have been able to transfer what I know about that to this application, but didn't! I am head smacking myself. I do use the RTTY position for all modes except SSB and it is good to know that it helps. Thanks for your help. You are a great resource. I will reach out to you through your normal email, if I have further questions. Be well 73 Matty WB2JCC

    • @Jerrythenerdful
      @Jerrythenerdful  3 года назад

      @@MattyMozzor output devices are matched to the load at peak power. As drive power is reduced, the output devices have less current and less voltage swing, this means ideal or optimum output impedance increases. Unfortunately output device efficiency decreases faster than input power as drive is reduced.
      The AL811H amplifier and other amplifiers follow this, too. Peak dissipation is at about half power.
      Running quiescent current near the lowest value allowing acceptable IMD helps flatten this curve. If it was class C dissipation would decrease with drive, but we can't do that!

  • @carlfrisky5158
    @carlfrisky5158 3 года назад +4

    Thank you Tom for this much needed video. I wonder how many ALS amps are out there? Would it be worth the time and effort for someone to start a service facility?

    • @Jerrythenerdful
      @Jerrythenerdful  3 года назад +7

      I'd like other people, especially the factory, to learn how to do this. I service these amps but they take so much time I cannot get more important things done. They just need to correct how they build and service these things. They cost a lot of money for this type of quality.

  • @dandee9141
    @dandee9141 11 месяцев назад

    Hi Tom, I am currently waiting for my ALS-1306 to arrive. In the meantime, just learning more about it. I read somewhere that Dentron started as a family-owned business and then the family separated and moved on to which is now Ameritron. I have the Dentron amp and have always liked it and figured Ameritron would be a great choice. After seeing your video, I was shocked about the manufacturing process. I will take a look inside and see what's up. Don't want to pay good money for something that may not be reliable. Good to know. Thanks for your video. Dan

    • @Jerrythenerdful
      @Jerrythenerdful  11 месяцев назад

      Denny was a good friend. Whoever told you that story is incorrect. Although Dentron was getting in trouble, Denny sold the company to Morris Messenger.
      Messenger accelerated the failure.
      Dentron failed because it stopped making a profit, nothing else. The primary reason it was not profitable was warranty service losses and some bad product investments, like a transceiver project. It was not a single-cause failure and was not family-related at all. Whoever told you that is "full of beans".
      Denny started Ameritron and Amp Supply after he left Dentron. Ameritron and Amp Supply were largely funded by John Moran, W8IOB, at Prime Instruments. Prime bought a lot of tooling and parts for Amp Supply and built the Ameritron stuff. However, the early engineering was exceptionally poor and the tooling was a bad investment. The original AL80, which was unfit for sale, was said to have been designed on a kitchen table almost overnight.
      In a financial readjustment, John took Ameritron and Denny kept Amp Supply. John and I corrected the Ameritron designs (at a cost of a hundred grand) and Amertron was more than doubling sales every few months.
      I left to go work for Heathkit as a contract engineer around 1987. As a result, John settled with me and sold Ameritron to MFJ. MFJ was supposed to keep Ameritron isolated from the MFJ manufacturing methods. Amplifiers are complex and fussy. They have to be built the same every time, and construction has to be good. Anything changed, even a parts vendor, must be carefully reviewed.
      I'm surprised at how careless they are with things. It is actually pretty sad.

    • @dandee9141
      @dandee9141 11 месяцев назад

      Hi Tom, thank you for the detailed information. Now I know why you are so knowledgeable about these amplifiers. My apologies about family related not sure where I got that from. I have the Dentron MLA 2500 which looks great inside and out and has always operated great for me. Now that it's been sitting for some time and is over 40 years old, I opted for a new amp. Watching RUclips on the ALS-1306 and discussing it on some forums I decided to purchase this amp. I wanted to get away from tubes and try solid state and see how that goes. I just started to look at repair videos to learn more about this amp is how I found your channel. The amp will be arriving next week. After watching your video, I think I should do a thorough inspection inside as I would like it to last. Not sure if there is a void warranty sticker on it will see. Appreciate you sharing your knowledge. Dan@@Jerrythenerdful

    • @Jerrythenerdful
      @Jerrythenerdful  11 месяцев назад +1

      @@dandee9141 The basic issue is an almost complete lack of assembly QC, but there should be variability to that. If you just work SSB and some CW it should be fine. I corrected my ALS1306 years ago and it has been running in the remote ham radio console here for years now without failure. It ran for a while, accidentally from a code bug, at over a kilowatt output on digital modes! They are fixable.
      I also have an LDMOS board that drops right in. It runs the LDMOS transistors conservatively, not at the limit, and it fits right to the OEM heatsink inside the actual unit. Other than the change in reliability and increased output, you won't know the change has been made. It isn't an easy change but it makes the amplifier rock solid.

    • @dandee9141
      @dandee9141 11 месяцев назад

      I noticed my reply didn't go through. Checking online LDMOS boards are all over the place. Very interesting. I checked CTR engineering but didn't see them. I wouldn't know where to start for ordering one and if there are any instructions for installation. Did you make or buy yours. @@Jerrythenerdful

    • @Jerrythenerdful
      @Jerrythenerdful  11 месяцев назад +1

      @@dandee9141 I designed and we make our own boards. Our boards fit the original OEM heatsink. The amplifier does not have to be butchered up in any way. Ameritron amplifiers are full of assembly problems. We have to strip the amplifier down to raw assemblies, test and repair those assemblies, and reassemble the amplifier. There isn't any way the general public could install a board, nor could we warranty the board.
      We have test fixtures for the control boards, filter boards, and other critical assemblies. They have to be tested outside the amplifier. There is more time and expense in designing test fixtures than the PA board!

  • @petertyrrell6690
    @petertyrrell6690 3 года назад +3

    Thank you Tom. That was most interesting.

  • @KT4RAM
    @KT4RAM 3 года назад +1

    Thank you Tom!
    My 600 should be there today or Monday. I feel confident that in your skilled hands it will be gone over with a fine tooth comb and anything that needs to be done or changed will be performed.
    Take your time and run her through the tests as long as you see fit. The bands are starting to open up a bit today but so far my 100w and homebrew dipoles are getting me some dx contacts although I have to work a little longer to break through the pileup's.
    Being on a limited budget (disabled former firefighter) what multi band HF antenna should i consider to put up?
    Some say the MFJ-1848 Hexbeam. At around $700 it's still a bit of coin to me but much less than some other options that I find.
    Thanks Tom.
    73

  • @JxH
    @JxH 2 года назад +1

    Ameritron is owned by MFJ, so that's about all the explanation that's required.
    It'd be convenient if websites like DX Engineering would offer a selectable Account option to 'Hide All MFJ brands', just to save time and grief.

  • @benthayer7357
    @benthayer7357 Год назад

    Thanks Tom for the great information. I see testing for various heat sink compounds online that suggest that some are much better at conducting heat than others. Given the importance of getting the heat from the transistor to the heat sink, do you have any recommendations or comments on heat sink compounds?

  • @billbrown3414
    @billbrown3414 2 года назад +1

    A friend has sent his 1306 back for repairs TWICE. Transistor failures both times. The last time it came back, the T/R relays did not switch properly. When he popped the top, the amp output relay showed evidence of heat damage. He changed the relay board and the problem went away. I feel the relay ratings are not quite up to the 1200w and may be contributing to a lot of the failures. Have you seen any similar issues with the relays?

    • @Jerrythenerdful
      @Jerrythenerdful  2 года назад +1

      Those relays are very good relays and handle a good bit of power. They are used in antenna switches and even in the AL1200 and 1500 amplifiers. The actual weak point of those relays is the receiving contacts tend to get contaminated with a very thin film and have erratic receive. This is very common in higher current relay contacts used at near zero voltage and current, and caused by lack of wetting current.
      I see very few relays bad and we service several amps using these relays a week. When the very occasional relay is bad, it is almost always intermittent loss of receive.
      We find backwards polarized capacitors, poor transistor thermal interface, bad wiring, bad soldering, wrong parts, poor filter alignment, circuit board changes that cause issues, and lots of things. But one of the less common things are the relays, and when they are bad, it is always loss of receive signal from contact contamination.
      This is pretty commonly understood with signal relays.
      en.wikipedia.org/wiki/Wetting_current#:~:text=In%20electrical%20and%20electronics%20engineering,contact's%20nominal%20maximum%20current%20rating.

    • @billbrown3414
      @billbrown3414 2 года назад

      @@Jerrythenerdful Thanks.

  • @LtNelli
    @LtNelli 4 месяца назад

    Thanks for the video, what is the torque for the FET screws?

  • @roberts5482
    @roberts5482 Год назад +2

    Milling aluminum is not very hard with the right cutter, coating, speed and cutting fluid. WD40 actually does a good job for cutting and drilling. Tap magic is the best for your own work. Most machine shops do not understand the importance of surface finish so this is an engineering specification fault from the design engineer of the product. I scraped the milled surface for my FETs' but you have to know what you are doing. I worked my way thru college working on the bench as a tool & die maker. You could also peen it for the final finish. You will have to use a piece if ground flat hardened steel and use light impact from a 5 oz ball peen hammer but practice it first and DO NOT GO CRAZY by beating the crap out of it. You will possibly do unreparable damage to the surface. In scraping it I used a Starrett planer gauge with a scraper I made and referenced the surrounding machined surface after I cleaned it up like Jim showed. Surface finish is specified by both RMS and direction. A proper roughness should be in the range of < 25 RMS and flattness should be about 0.0002" per inch. There is no excuse for a shop not to be able to produce this specification.
    Another suggestion is to always pay attention to the galvanic acceleration / corrosion possibilities. Download a chart and hang it on the wall. There are some thermal paste made with silver added used for computer processors. If it's a flat surface i doubt the silver will increase the coef of thermal conductivity. I believe it to be a gimmick started in the days of the early Xeon processors. Never put that on an aluminum heat-sink. They are on the opposite side of the galvanic charts, "anode / cathode". With the added heat, that mixture will instantly corrode to a big mess of black goo. Just try to silver solder aluminum one day and you will se an instant reaction. IF you like to shoot Ar's never put graphite in a an upper receiver. With rain, it can ruin a weapon.
    Even fasteners can have detrimental effects to the parts being fastened to and in. Certain stainless steels are not favorable against some aluminum. Go to McMaster Carr and look at their fasteners. They have good info on the materials, specifications and usage. Their quality is extremely good. The crap you buy from Home Depot or Lowes is a lot higher priced and no where as good. The metals they sell have actual certifications for the material and is about half the price of the big box stores.

  • @matthewoakley2376
    @matthewoakley2376 2 года назад +1

    I wonder if the past two repairs that’s been done on mine have had this kind of cleaning up or not? Thank you sir.

    • @Jerrythenerdful
      @Jerrythenerdful  2 года назад +4

      While heatsinks pretty much always need cleaned up, a variety of other QC problems are also behind FET failures. We find a host of problems, including poor soldering, solder splashes and hardware rolling around inside, low pass filter construction, and non-functional protection circuits. If a service person only changes a bad part, like a bad FET, the amplifier will just fail again. It is always possible to have a bad component, nothing is ever 100%, but it is important to take the amplifier completely apart and inspect every critical area.

    • @matthewoakley2376
      @matthewoakley2376 2 года назад +1

      @@Jerrythenerdful is this something you’re still in the business of doing? Mine is at Ameritron now and FET’s are out of stock until June.

    • @Jerrythenerdful
      @Jerrythenerdful  2 года назад +2

      @@matthewoakley2376 We repair a few Ameritron FET solid state amplifiers a week. We always keep FET's in stock, we try to keep somewhere around one hundred on hand because they have to be gain matched.

    • @matthewoakley2376
      @matthewoakley2376 2 года назад

      I’m in need of service on the unit you repaired for me. Is there ANY way you can look at it?

  • @littlebear5219
    @littlebear5219 Год назад

    Thank you Tom this video is of great help

  • @kcpupdog
    @kcpupdog 9 месяцев назад

    I have a AL-811 Ameritron amp. For some reason, it started blowing fuses. I have 20-amp fuses in it and it runs on 120 vac. I just put 3 new tubes in it today. It tuned up ok and had a idle plate current at 60 ma like it supposed to have. Everything seemed ok and I made one short contact and after setting there for a few minutes it blew both 20 amp fuses. I wasn't even keying the mic or anything. Looks like I changed the tubes for nothing. Any ideas?.

  • @DonDegidio
    @DonDegidio 3 года назад +1

    Hi Tom,
    Very interesting video. I don't understand why they don't use a mill of the proper width and make just one pass. What would they need, a mill about 1.5" ? Stay safe. 73 WJ3U

    • @Jerrythenerdful
      @Jerrythenerdful  3 года назад

      I'm not sure what drives the carelessness. Perhaps production people do not understand there can be up to 150W of heat in something around 1/2 square inch if the flanges were perfectly mated. The dirt and debris coupled with the poor surfacing is a deadly combination. Then you throw in all the bad soldering and it is a disaster for mortality rates.

    • @DonDegidio
      @DonDegidio 3 года назад +1

      @@Jerrythenerdful Hi Tom,
      I'm a home machinist and look at that project and think why make multiple passes when one would do the job. The finish would also look much better. I know you can't have ANY debris under the devices. Stay safe. 73 WJ3U

    • @lizzyfan1986
      @lizzyfan1986 3 года назад

      @@Jerrythenerdful I know, quantity not quality...there I said it....you designed a fine machine but unfortunately got in the wrong hands

    • @Jerrythenerdful
      @Jerrythenerdful  3 года назад +1

      @@DonDegidio When working with people, methods have to be selected to fit best overall outcomes. For example I initially used a copper spreader under FET's, but the processing in their own machine shop was so poor the copper had severe surface irregularities. When that was pointed out they started to hit the copper with a belt sander. While this knocked the lips around holes down, it left the surface rough. The former vice president and I decided to get a thicker extrusion and only deal with one piece of metal. They were supposed to just barely skim the heatsink to get to flat surface of a very low Ra in the 6-8 u-inch range. Milling at best is in the 20-30 range. The choice was mill flat as best as possible and hand wet lap with a block, or just do one operation with a proper wheel on a surface grinder. The machine shop could or would not fixture to pick up on the mounting surface as a reference, so on their own they decided to locate off the fins and mill deeper. The entire thing about processing heatsinks should have taken a few days of engineering time, but it consumed months or years.
      The heatsink area is a perfect match for the fans, and both are adequate for power (it took weeks to design the custom extrusion to get rid of the copper spreader) but they dismissed surface grinding and cleaning boards and benches because of either cost or just simple lazyness. The result is the finish common in these amplifiers.
      They blamed the FET's or some nonsense about "FT-8 spikes" and wanted to go to a higher power single device, but the former vice president and I pushed back. If they cannot handle 500 watts of heat spread out on four devices per module, packing that heat into a even smaller contact area would be a real disaster!

    • @DonDegidio
      @DonDegidio 3 года назад

      @@Jerrythenerdful Hi Tom,
      Yes, if they can not maintain a flat surface quality, then going to one device would be a disaster. Stay safe. 73 WJ3U

  • @timmyers3428
    @timmyers3428 3 месяца назад

    After having taught soldering techniques in the USAF a lifetime ago, this factory soldering looks pretty sad. Once you have soldered enough connections your flow (pun intended) should be pretty smooth.

  • @miker8379
    @miker8379 3 месяца назад

    Is there 1 thermistor or 4?

  • @kenburchfield1763
    @kenburchfield1763 2 года назад +2

    My 1306 is less than two years old. Been in shop twice. Both times transistor trouble. It’s dead again with the same problem. It is a $3000 piece of junk now.
    Can you repair it correctly for me ?
    Phone number ?

    • @Jerrythenerdful
      @Jerrythenerdful  2 года назад +2

      Hi Ken, These amplifiers come with a multitude of problems. If only the FET is changed and all of the other problems are not addressed, they will just go right back out again. Besides the heatsink rough finish, we find defective or wrong components, non-soldered connections, and non-function protection circuits. The efficiency also has to be measured. Unless the efficiency is 50% or higher at full power, which means transistors are around 150W dissipation or less, transistor junctions will get too hot. This will shorten FET life.
      Our contact information is here:
      www.ctrengineeringinc.com/contacting-us-please-read/

  • @poseypapusdiazfamily4630
    @poseypapusdiazfamily4630 7 месяцев назад

    Do people add copper heat spreaders?

    • @Jerrythenerdful
      @Jerrythenerdful  7 месяцев назад

      No. A copper spreader is not necessary with four and the transistors spread out over the heatsink. If all of the heat was in one spot a spreader would be required. The major thermal issue, if the heatsink finish is good, is thermal resistance inside the transistor.

  • @MM0IMC
    @MM0IMC Год назад

    It's ridiculous that MFJ's QC never caught these problems before they left the factory. I fear that QC hasn't improved any... 🙄

  • @phanrangsam
    @phanrangsam 3 года назад

    Is there a Video that shows how to SLOW the Fans on the ALS 1300? I should say a Video for Dummies?

  • @Brenda-jf2pe
    @Brenda-jf2pe 2 года назад

    It’s out there since mfj bought Armatron quality is a thing of the past. KJ7TBR

  • @bigfoottoo2841
    @bigfoottoo2841 3 года назад

    I always lap my transistors

  • @patricklozito7042
    @patricklozito7042 9 месяцев назад

    Terrible, just terrible. If my soldering at work looked like that, I wouldn't have a job.

  • @QuikAdjuster
    @QuikAdjuster 3 месяца назад

    Sure looks like bad QC department..obviously no trained QC folks. The QA department sorta let loose a horrible production scheme.

  • @bigfoottoo2841
    @bigfoottoo2841 Год назад

    Don't forget to lap the transistors

    • @Jerrythenerdful
      @Jerrythenerdful  Год назад

      No sir. Do not lap the transistors. They are already smooth and contoured slightly convex. The last thing you want to do is lap the transistors.