I have a 991 and after 15 days, it was sent back to Yaesu due to finals blown, HISWR, and same story everybody knows.Once repaired the same problems occurred (HISWR and ATU not working properly) but Yaesu Italy (CSY) has been so gentle to handle again this radio, noticed the fact that the internal ATU did'nt even try to match and gave me back the radio with some fixings. The first week the 991 was perfect, the ATU worked perfectly with my R8 but suddendly something happened and the HISWR was back, same initial conditions.I think for some unknown reasons ATU memory screwed up...
I decided to try an external tuner, a friend of mine gave me temporary a LDG AT-100proII that worked perfectly and I decided to buy a LDG AT-200proII, so I could use eventually with TS-950SDX (150W) Unfortunately the entire LDG shipping was canceled due to import problems from italian distributor I don't know. In the meanwhile I've seen many of yout are using MFJ tuner with this radio and are happy.
The question is: to buy LDG tuner or MFJ (and eventually the cat cable) ?In your experience wich model best matches this radio and have better tune ratio ?
I have used both the MFJ-939Y and the LDG tuners, the AT-200Pro and the AT-100ProII with my FT-991. The MFJ-939Y works with the tune button on the 991, it is very fast and matches just about anything. The LDG 100 and 200 have an auto tune mode but they do not work with the tune button on 991. I changed the menu item in the 991 so CW would work in SSB mode. So if I key the 991 either with a small switch or CW key, the 991 will switch to CW and activate the LDG tuners. I set the power in the 991 for about 10 watts in CW, power is saved for each mode. With the LDG tuners in auto mode this works pretty well and it is like using tune button on the 991.
Both are great tuners but assuming the MFJ-939Y lasts, holds up well with time, I think it is a better deal, less expensive and works with the tune button on the 991. Also, I have had LDG tuners for years, used them in many ways, they last and never a problem. I even asked LDG if they would make a cable for their generic tuners to work with the tune button on the FT-991 but that was many months ago, nothing heard. The LDG YT-1200 works with the tune button on the FT-991 but its price is higher.
I don't know if the ATU is working correctly or not.
ReplyDeleteI have a new 991 and a 66-67 foot end fed longwire.
When I tried it on 160m, pressed the tune button momentarily, showed tuner on display, pressed for a second or so the relays chattered tuner display flickered and then stayed on stead. Meter set to SWR and when I talk there is no reading on the meter.
Tried the same on all other bands, no chattering, on some of the bands the tuner indicator goes off.
Only when talking on 20m (IIRC) does the SWR meter show a reading (up to 3).
No bands show HI-SWR.
Also get the same SWR meter display if I turn the tuner off (no tuner indicator).
To me that suggests that my wire is resonant on all bands, surely this is wrong.
I seem to be doing everything as per the manual.
I also have an Icom Pro3, that can be heard tuning on all bands.
Am I doing something wrong?
The internal ATU is very limited... Almost a joke for a radio that is suppose to be a field radio. On a good day it will do 3:1. I suspect you antenna is far worst then that. A typical LDG ATU is 10:1... I have the new MFJ-939Y hooked to my FT-991. It will do 32:1. I have a G5RV at 30 ft and sort of a inverted V configuration.. Really UGLY.... The MFJ-939Y will load 160-10 meter with ranging from 1.1:1 to the highest I have seen is 1.7:1. It is super fast also. That said the internal 991 ATU should only be considered when you have a tuned antenna that needs the SWR lower at one end and never considered for any end fed long wire, unless you want to fry the finals..
ReplyDeleteI added the LDG YT-1200 to my two FT-991's after hearing about all the final transistor failures ( I am now wondering about the ALC issue) but frankly I am unimpressed. I can't get below 2.5:1 on a
ReplyDeleteGood G5RV Jr. At the upper half of 20M But 1.4:1 at the low end. That tells me the
Ext. tuner is not appreciably better than the internal Yaesu version, which under acceptable conditions like a EFHW is just adequate and as fast. I have tested this premise to verify.
I am going to buy a MFJ-939Y based on your experience.
We shall see
I am using a super UGLY G5RV and a few nights ago I set the radio to AM and went for 160 meters to 10 meters and was blown away with the fact the worst SWR was way less then 2:1 and most were 1.5 or less to 1. The YT-1200 I believe is 10:1 and I am sure based on my past experiences with LDG is quite good. However the MFJ-939Y has a 32:1 range and suppose to have double the caps and coils... Not sure how true this is since I have not opened it yet (My nature is such that I will one day). All I know it works with a seriously bad antenna. Even worked South Africa late one evening on 40 meters with the G5RV which shocked me. I am sure it will work wonders with a EFHW.... The antenna did not load my G5RV on meters..Darn...
ReplyDeleteFYI – if you order the MFJ-939Y the Yaesu cable come with it.
ReplyDeleteHere is the list of cables for the radios based on what might not be the latest manual..
ReplyDeleteMFJ-939I Icom IC-706, IC-707, IC-718, IC-725, IC-728, IC-736, IC-738, IC-746, IC-756, IC-7000
and compatibles
MFJ-939K Kenwood TS-50S, TS-450S, TS-480HX, TS-570S, TS590, TS-690S, TS-850S, TS-870S,
TS-2000, and compatibles
MFJ-939Y Yaesu FT-100, FT-450, FT-847, FT-857, FT-897, FT-950, and compatibles
MFJ-939Y3 Yaesu FT-1000MP and FTdx-9000
MFJ-939Y4 Yaesu FT-2000, and FT-5000
You will notice the FT-991 is NOT on the list, which tells me they have not update the manual as of yet.
Sudden changes in ATU performance at my QTH have always been precipitated by some manner of change in the antenna/transmission line arrangement. Such changes have included:
ReplyDelete1) Rain in progress
2) Yard man moving the coax so he could mow around it, thus resulting in it coming off at an angle from the feed point, rather than hanging straight down
3) PL-259 barrels coming loose at balun and choke connections due to the whole antenna flapping around in the wind
4) Transmitting into the wrong antenna on the wrong band
5) Break-down in the balun or choke components (rare, but happened once)
6) Snow in progress
7) Moisture getting inside coax fittings (must waterproof these extremely well)
8) Common Mode Current problems (especially with OCFDs)
9) Utilizing the wrong ATU (see below)
10) Damaged coax (one yard man deducted $175 from my bill because he forgot to mow around the Bury-Flex he knew was there; he's never forgotten since)
11) Ground loops in the shack (not grounding when you should; grounding when you shouldn't)
12) Trying to force the ATU to find a solution on a band for which the antenna is not designed
As you undoubtedly know, not all internal ATUs are alike. Elecraft and Ten-Tec employ extended ones (10:1), Yaesu likes limited ones (3:1). I did not buy the FT-991 for its ATU. I bought it for its DC-to-Daylight coverage and for its otherwise decent features. If I use it portable, an external one will also tag along.
Ninety-five percent of the time a change in SWR will stem from antenna-transmission line anomalies. The other five percent derive from miscellaneous issues, not least of which involves forgetting to reduce power output (20 watts and below) during the matching operation.
The new LDG Y-1200 matches perfectly 6-160. Check the LDG website it has all the radio settings for the 991. I have it and it works great. The MFJ does not do 6m John KB9FQB
ReplyDeleteSo i just bought the FT-991, and read through this thread and bought the MFJ-939Y. The post at the top says to put jumpers on JP# and JP1. I haven't opened the cases yet where are they located?
ReplyDeleteSet the MFJ-929 menu for yeasu interface
ReplyDeleteFT-991 menu 143 should be set to External
power the tuner on first, then the Radio
Pushing the tune button the radio will initiate the process
You need jumpers on JP$ and JP!