Further to my earlier messages, I do have a little more information to pass on.
Here in the UK at least, there have been changes made to the PA circuitry to improve the PA's ability to handle a high SWR. Also some changes to the ALC circuitry & calibration. All new 991's in the UK have these mods.
None of this will probably not come as any great surprise to many on this list. I think we should applaud Yaesu though for dealing with this issue and standing by their customers and the reputation of their products - anyone purchasing new from now on should not have any issues going forwards. I would suggest anyone with any issues should contact their local dealer or service centre for advice.
I hope that helps. I have to say, I have been very impressed with this radio in the first week of ownership - can't wait to use it as my main "holiday" radio!
Before anyone asks, I do not have detailed information about the mods - some information in the corporate world is of course, sensitive and not for public release - quite understandably, give we hams have a penchant for "fiddling" with radios!
I trust I have not breached any "confidentialities" by saying as much as I have, but I wanted to reassure group members that Yaesu have a handle on this.
As I say, I suggest you contact your dealer or service centre if you want further advice and reassurance.
When were these changes made ? From what month ?
ReplyDeleteIs it Yaesu UK or Yaesu Japan that are doing the mods? I ask as some dealers get stock direct from Japan and others get their stock from Yaesu UK.
ReplyDeleteI have taken delivery of a new FT991, set it all up into a resonant antenna (a 40M Dipole fed with 450R Ladderline), and it is only putting out 25W PEP on LSB.. .... I tuned up my ATU with my TS-590 on two other bands and then coupled up and keyed the 991, with the same results. Only about 10W on AM or FM..... I therefore think from all the posts on this topic that the necessary mods may have not been done on this radio. Very disappointing, as it was bought for me by my son for Christmas. It was Purchased from Martin Lynch in UK and the Serial number is 5L220095.
ReplyDeleteSecond point is that you are only given 15 days after purchase to Register for Warranty - and my son bought this on 16 November, but brought it unopened, here to me three days ago on the 8th of December.
I would like some advice on this before I phone MLS, with the problem.
What power does it put out into a dummy load? You do really need to connect a dummy load to eliminate the other parts of the system regardless of how it might look.
ReplyDeleteIf you select FM then what is the power setting on the radio in the menu, specifically is it set to 100W?
If you select AM then I would expect the output power (without modulation) to be set to and read 25W or thereabouts. (I realise that it’s only reading 10W).
Note that the power level setting does change with the mode so it you’ve set 50W on SSB you may get a different power level setting for AM and FM. Check that the power level settings are as you would expect.
If the 40m dipole is fed with 450R ladder line then really the aerial is a doublet since the impedance at the transmitter end of the ladder line could be pretty much anything depending on the length of line. If you use an external VSWR meter what match is shown before you engage the FT-991’s internal tuner? If the match is worse than 3:1 it is out of range of the internal tuner. Note that the TS590’s internal tuner may well be able to match the aerial system.
If the radio is new I would call Martin and not worry about the 15 day warranty. He will have a record of the radio and will likely look after you in my experience.
Hopefully you’ll get it sorted in the cold light of day, the FT-991 is a lovely radio to use with many facilities.
I would imagine Yaesu in USA will have access to the same info as we do in the UK - so check with your dealer - hopefully they should know about this by now. If not they can always contact Yaesu UK(!)
ReplyDelete