Because I burned power amplifier of my Juma TRX2 and was couple of weeks without rig, I decided to buy a new one. Now I am very happy owner of brand new Yaesu FT-817. The first summit has been done. It is nice and complicated, perhaps at the beginning too complicated for me. All other basic things I have found and learned from Operating Manual, but setting of SWR view is invincible task for me so far. Let me know how to get SW display on?
It is easy to find Operation Function row nine and select “MTRswr”, but even I push “F key” button shortly or longly I am unable to change SW view on. It stays allways as S (S-meter) display. Just now I am quite frustrated, because I feel me stupid (perhaps I am, but I would not be). You who are more familiar with FT-817, let me know what I do wrong or what I should do other getting SWR view on?
Ou yes - Juma is now up and running again, but I think so that I will continue field operations with FT-817 from this point forward.
In reply to OH2NOS:
The SWR is only displayed during TX. During RX it remains on signal strength (S-units).
With the setting MTRswr just key the transmitter and it will display SWR. So you can read S-units during RX and see SWR during TX. Well not really SWR but reflected power.
On row 9 select “MTRswr” as you have done. Then press the F button “shortly”.
Now your display should be S meter when receiving, but SWR display when transmitting. If the SWR does not show, then you’re not transmitting - so you may need to select the [BK] button (another function row).
Hi Saku,
Pushing the F button slightly let you scroll through the 3 multi-function buttons under the display.
As said, there is one position (row 9) that displays:
PWR MTR
and just right the MTR label it displays what it shows on transmit: it could be:
Power / ALC / SWR or MOD
press the middle button repeteadly until to set it to SWR. You should see then:
PWR MTR swr
S is always shown on the display but on TX it IS Swr!
Good luck!
73 Ignacio.
In reply to OH2NOS:
This link may help, only English though. Quick simplified sheet at the end.
Good luck
Rob
G4RQJ
www.radiomanual.info/schemi/FT817_user_guide.PDF
In reply to OH2NOS:
Hello OM Saku,
after 4x replacement PA MOSFETs in my FT817 I heartly encourage to protect PA with this simple and perfect mod: http://www.mods.dk/mod/_1/4142_SV8YM_FT817_final_amp_mod.pdf ,
after this mod my PA lives six years without any problem. No problem to send .pdf by e-mail.
It seems it is only some FT817s that have the PA self-oscillation problem.
I have had my FT817ND for almost five years and I have never encountered this problem.
The serial number of my FT817ND is 9H560098.
In reply to G3NYY:
Hi Walt,
yes, it is possible. I have FT817 (no 817ND) from the first years of production, It was usual and frequent problem as i know.
Hola a todos.
He tratado de leer todas las respuestas, traduciendolas en Google.
Y hay una posibilidad que no veo explicada.
Si el 817 esta bien configurado, en RX, se verá la fuerza de la señal S-meter,
Y en TX mostrara ROE, pero solo si la hay. Si no tiene ROE usted no vera nada.
Si usted no ve SWR, pase a POW, o bien a MOD, y vera si su 817 funciona bien.
Espero haberle ayudado.
Saludos de EA2EX
Hello everyone.
I have tried to read all the responses, translating them into Google.
And there is a possibility I have not seen explained.
If the 817 is well set in RX, you will see the signal strength S-meter,
And show TX ROE, but … only if there is. If you do not you will not see anything ROE.
If you do not see SWR, go to POW or MOD, and see if your 817 works well.
I hope I have helped.
Greetings EA2EX
In reply to OM3CUG:
I bought my first FT817 in 2002 and used it heavily for several years without ever experiencing the PA problem. I eventually decided it was getting worn out and replaced it with an FT817ND and have had no problems with it (touch wood!) Although I frequently saw mentions of this problem on the pre-ND FT817 I believe that most owners of the rig never had this problem - after all, many thousands were produced. I have wondered if it was due to one component being at one extreme of its natural scatter in characteristics, but who knows? (Besides Yaesu, and last I heard, they weren’t telling!)
Si el 817 esta bien configurado, en RX, se verá la fuerza de la señal S-meter,
Y en TX mostrara ROE, pero solo si la hay. Si no tiene ROE usted no vera nada.
That is a very good point! The “SWR” meter actually shows reflected power ONLY. If you have a perfect match to the antenna, there will be no reflected power so the SWR meter will indicate nothing! You might then think (mistakenly) that it’s not working. In this case, switch to either the Power Output or Mod options and see if there is any indication on the meter when you transmit. If so, you are OK.
The problem was with the old PA devices used in the non ND model. When power is supplied to the rig via the external socket, the PA sees the supply regardless of whether the rig is powered up or not.
The old devices became obsolete so the ND model user a different type of device which is more rugged. My 2001 vintage FT817 ate it’s PA and wall warts charger during charging whilst the rig was turned off. Yaesu repaired the rig by fitting an ND PA board.
My FT817 has been perfect ever since, better than when new!
73,
Colin
The UK Yaesu engineer I spoke to knew exactly what the problem was, he diagnosed the fault over the phone. Yaesu were well aware that they had a problem with the original FT817. Shame that my rig was about 3 years old by then!
The problem we know of comes from the fact it’s easy to find out problem reports on the net now. At one time nobody would have known there was a recurrent problem. Now anyone who had a problem will post the info on Facebook along with the other minutiae of their life. What happens then is it’s easy to find people who have had problems, what is harder is to find out the percentage of people having no problems. You only need a few vocal people for the reputation to grow.
In my case my 817 failed. It had the classic signs of PA failure so I ordered another PA and got a board using the new devices. It took under an hour to strip the old PA board and fit the new one only to find my 817 was still duff. Digging about with the scope I could see the RF signal disappear on one of the driver FETs… it had a gate <> source short. Of course I should have done that 1st rather than believing the internet lore. In the end I got a well known SOTA man to the North to swap the drivers as I didn’t have a SMD hot-air gun and didn’t want to Manchester the tracks on the board. I have a spare PA board now, the FETs measure OK.
Did the PA cause the driver to fail or was it something else? I don’t know but this is one 817 that has had a PA swap when none was needed.
The case of the 817 which has had 4x PA replacements is interesting. After the second PA failed I’d be looking for something in the rest of the 817 that was causing the failure. To be honest, I’d have fitted a 3rd PA and sold it on eBay! What do mean you’re outraged at the thought that the world’s favourite Tat Bazaar may be a source of suspect items?
I dunno, Colin - a lot of people complained that the PA failed when the rig was powered down but the batteries left in it, and recommended removing them: I myself left (and leave) the batteries in and only leave the PSU on with the rig powered down when recharging the batteries, but that would be ten hours or more depending on which set I had in the rig, and in an overnight charge it might well go for some hours after completion with the PSU still on, but I had no trouble. This is the puzzling thing about it, if it was a design fault such as you describe then logically it should affect all the early 817s, but in fact it only affected some of them. Mine got heavy use - I filled nearly four logbooks using it, and yes, I had one or two problems, but never that one.
In reply to OH2NOS:
Thank you for many answers! My Yaesy is 817 ND model and based on statements given it is well working model.
First, the SWR view problem was my wrong understanding. I did not understood that SW view appears only when you send. I tested and so it works.
Second, when I sent on 14 MHz not any “dashes” appeared on the display. And why, because real SWR with my gp is about 1.12. But when I sent on 10 MHz two “dashes” appeared. On this band real SWR is more than 2. On 7 MHz I got from zero to one “dash” depending on frequency. And vice versa on 15 and 28 MHz did not appeared any “dashes” because real SWR is about 1.1. My summary is that SWR view works as it should and it really shows reflecting power, not real SWR. This functionality is worse than in Juma, which has two decimal presenting digital view.
But because I need to learn to live with this functionality I need to have well tuned antenna and/or buy antenna tuner which has SWR measurement. Today my link dipole is quite well tuned and I use tiny miny MFJ-902 antenna tuner which works with Juma’s SWR measurement like a dream!
If I would buy new antenna tuner for FT-817 ND, which would be the most appropriate model? My requirements are small size and accurate SWR display with 5W.
73, Saku OH2NOS
Ps. So far I have used my 25 year old Bencher paddle in summits. Today I got a new mini paddle via post and now I am ready to continue summits as “more professional manner”. ;-D
If you select operating mode 9 (see pages 13-15 in the manual).
The B button is then meter selection and allows you to switch the meter mode while transmitting between power, ALC, SWR and modulation level.
Pressing the A button allows you to switch the output power betweem 0.5, 1, 2.5 and 5w output.
The PA failure of the FT817 does happen but a large number of the early failures were caused by those folks who thought they could tweak their rig to give 10 watts - you could but the lifetime of the finals was now finite (and short). When the PA fails it usually takes at least one of the drivers (in fact on most radios, all makes, that I have with PA failure it is usually the drivers not the PA devices that fail).
If you replace the FT817 PA without checking the drivers you wll be waiting on a second failure. The radio is perfectly capable of producing 5 watts out with only one driver transistor functioning although the output waveform (and spectrum) are far from acceptable, however, in time the second device will fail and you are back to square one. Price of a pair of driver transistors is minimal and, with care, are easy enough to replace.
Just for the record top three failure modes for the FT817 (all models):
DC socket on the rear (90% of all repairs on 817’s)
Choke in DC supply and the associated burned tracks
Volume/RF Gain control bent (because the radio was dropped)
The PA comes a long way down the list
Good rugged little radio, just remember its limitations (YMMV)
73
