If they keep on casually messing with those power levels like that, I'm afraid that amp doesn't have much longer to live. All of those protection circuits cannot act quickly enough to protect the amp finals. You tune first with amp off at 10w, then turn on the amp on after tuning and it MIGHT last longer. This is REACTIVE power that involves very high voltages (inductive loads) or very high currents (capacitive loads) at the instant PTT is pushed; the transceiver at high power (50 watts) may fold back later on, or the tuner may cutout the amp but that too will be later on, after the finals experience the high inrush or voltage peaks.
I have been all over your youtube page this past weekend. I think that there are only four or less that I did not get to view yet. I was very interested in the Apache Labs one. Do more on the SDR's.
All this MFJ equipment together I keep waiting to see smoke, That antique FT1000 is a NICE RADIO!!! I would hate to fry it! I have used QRP for years, and its definitely safer if you are unsure what you are doing. High SWR is never a good thing, but when your total output power for the rig is 10 watts it will be ok! HIGH SWR at QRO levels and your gonna fry something! I recently got my first amp, and I am not going to claim to anyone that I am a QRO expert! I know my HENRY 2KD Classic is designed for 1.2kW , I have been told it will go full 1.5kW but have been encouraged to slowly adjust drive and keep it at the 1.2kW level that it's not worth risking 2 3-500Z tubes to get 300 more watts out! Having recently relocated my new antennas are currently rolls of wire, I am going to do my best to trim them as close to resonant as possible so the tuner has little work to do. Sunspots suck so bad right now I am going to focus on 80/40/20 wires and save for a tower and hopefully as we slide into the next cycle I can have a tribune beam up. I am going to study how to tune my AMP before I ever put power to it! 73 hope your MFJ-998 is doing well
I Know its not going to work at that match, but its the fact.. MY internal tuner on my Yaesu FT450 will only tune something 3.1:1 swr or better. This unit will tune 32:1
+HamRadioConcepts and that is a 1300 watt amp and you are driving it to hard. Also it that beam was one with traps that also would not be good. Both of those pieces are great and love to have them both but really the testing is a bit off center.
+1903A3shooter You saw in the video it i was not driving with the full 100 watts as recommended. At one time Ralph had it over 100 watts because he has a 200 watt rig. Other than that, it exceeds the 1200 watt that the amp is stated to have at only 70 watts drive. Why do you say a trapped 4 element beam would not be good? The beam was designed for full legal limit and he has been using it that way for many years.
I wonder if the toroidal inductive coils get hot during prolonged operation? They are not as efficient as air wound coils. I'm thinking about buying this tuner to run with my Acom-1000. The Acom amp can handle up to 3:1 SWR by itself. I generally don't like to use antenna tuners and prefer resonant antennas. I do need a tuner to operate on 80 meters since a dipole has a very narrow resonance and can't even cover half the band without a tuner.
@@lizzyfan1986 Troll my ass. I've held an amateur radio license for over 26 years. I even own the exact same tuner he's testing here. An ALS1300 is NOT designed to run full legal limit, it is supposed to run 1200 watts pep to stay clean. Running it wide open at 1500+ makes it a dirty splatterbox. Tuning up trapped Yagi's on bands they aren't supposed to work on is bad for the tuner and the traps. Unless you have any experience beyond running your yap, STFU.
I'm surprised MFJ allowed you to post this review. I don't know the specs on your friend's beam. However, I modeled a 20M dipole on 18.1 Mhz. Not knowing how much (or what type) of coax your friend uses I used 100' of LMR400. On 18.1 Mhz the dipole exhibited a resistive impedance of ~8 ohms and capacitive reactance of ~37 ohms. This translates to an SWR of 10:1 at the tuner and an antenna system loss of ~4db. Your friend was pumping 1500 watts into the MFJ-998. And of that 1500 watts, 870 were being reflected back to the tuner. How long do you think that tuner and your MFJ amp will last having to dissipate 870 watts? The MFJ-998 is a very good tuner. I've owned one for about 5 years and never had a problem. However, a review like this sends the wrong message to an unknowing amateur. Just because your meter shows a low SWR does NOT mean you have an efficient antenna system.
Question Is there a way to set the fwd power meter so I can view actual power(esp with my amp connected)while transmitting?? The only way that I have been able to accomplish this is to switch my Icom 7300 to either fm or rtty. I can then see 450 watts out. But if on ssb, the mfj shows fwd= 24.0 Thanku William
Nice video A question. When tuning up on my 993, I was told that I can tune with my 7300 set to 100 watts and the radio will automatically cut bk during tuning. But, with the 998, does the same apply, or must I reduce power manually?? Thanku Billy
I am going to use an Ameritron ARB-704 keying buffer between my Yaesu FTDX10 and my Heathkit SB200 amp - I am confused how I would connect the MFJ 998 to this set-up? I see the Amp Enabe In and Amp Enable Out jacks - but how would this all work with my ARB-704 interface - kind of confused!!!
I thought the 1306 was a 1300 watt amplifier? I know my ICOM PW-1 is only supposed to be a 1000 watt amplifier but it will do 1500 Plus as well with high drive.I run it at 1200 watts PEP on all of the HF Bands with just 35 watts of drive & it does 900 watts on 6 meters with the same drive.
This is Vernon Lewis - W7VPL, I am using an antenna tuner MFJ-993 - My question:: I will be using a MFJ-1786 Loop antenna, which is on order from DX Engineering - , By connecting the Loop tuning box to on of the antenna tuner coax outlets, which there are two, could I feed the Loop tuning from one of the outlets?? How would I be able to keep that tuner connected and be able to run the Loop anntenna??? Do I have to take the tuner out of the system and run the radio directly to the Loop tuning box??? Vern
You cannot run an antenna tuner with the 1786 loop. There is no need for a tuner, it comes with its own tuner when you buy the 1786. The tuner control head sends power over the coax to operate the motorized butterfly capacitor in the loop, and the 1786 is it's own antenna/tuner BUILT into one. Do not hook up the 993 with it. It is not intended to be used with any kind of tuner.
He said he was going to go the full 1500 Watts with an ALS-1306. Well, the ALS-1306 isn't rated for 1500 Watts, so he's taking a chance.. I could have done without the guy chewing his fingernails. Of course the amp has to be in standby while tuning. You don't want to hot switch 1200 Watts!
I just bought one, all I can get mine to do is say "HUH" Increase power" I increase power, same thing. If I key down manual CW, it starts to tune, then stops, with SWR 3.5 or higher. Think I'll sell this lemon and go back to manual tuner.
I'm trying to tune 30/40/80 on my 160m inverted L, 4 radials. I am having several issues. The tuner never auto tunes when target SWR is exceeded, and yes it is in auto mode. Sometimes when I xmit, the freq. display is all over the map, tuner not recognizing freq.. Sometimes it will tune to flat SWR, say on 40m, but if I change bands and come back to 40, the settings apparently have not been saved, and then won't retune to SWR below 3.0 or so. I get a lot of "Huh" errors. SWR on those 3 bands are below 4.7 before tuning. I recently bought this from another ham so perhaps he sold me a defective tuner, it just does not perform like the ones in the videos I watch.
Well it's possible it has been damaged somehow, Because normally it tunes and saves the swr. But i have heard of this issue which is the IC logic chip that is damaged when either too much power was used, the tuner got a power surge, or using too much voltage. MFJ can send you a replacment IC chip you can plug in if they have one, contact them. But normally, it is a great tuner, and a lot of people like it. But with all electronics, misuse can damage it. In this video I stress tested it as you can see, to test its limit, and so far it never failed.
Yes I have heard it was good tuner. Not really planning on really high power through it but wanted an auto tuner that could withstand the key down modes bettter. Can't hurt to replace that IC, I'll try that before giving up on it, thanks!
Thought I'd let you know I removed the cover, found the far left torroid leaning to the left about 40 degrees, and the center single torroid so so loose that I can easily rotate it.. not sure if that affects tuning or not.. the logic chip is $20.00
THATS JUST WRONG.BAD ON EQUIPMENT...YOU REALLY NEED TO LEARN YOUR EQUIPMENT..DONT LOOK GOOD ON YOU AT ALL..PLUS YOU ARE ON VIDEO BLOWING PASS THE 1500 WATT LIMIT..
Dave Hill stress test. But the real concern is this.. Do you think nobody exceeds the legal limit? I don't have an amplifier, This was only a quick test. Thanks for your input.
