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eHam Forums => Station Building => Topic started by: KB1VCZ on May 01, 2011, 06:28:35 PM



Title: fT-857d Selector Knob Malfunction
Post by: KB1VCZ on May 01, 2011, 06:28:35 PM
Ok, I'm not sure if this is the best place to post this but here goes.

Today I experienced a very odd malfunction with my 857D while tuning with the selector knob.

I was moving up the dial and then back down and realized that the frequency wasn't keeping up at times wouldn't move despite slowly turning the selector knob a couple of stops.

This happened when I first turned on the radio and during normal ops, it was as if the knob was "slipping" for lack of a better word.

This soon went away and things were normal, but then it came back again.

Didn't matter what band, but I did notice it most prone to happen while moving own the dial.

At one point, I watched as I turned the knob a couple clicks and the frequency also moved, but then when I removed my hand, like a ghost in the machine, the frequency readout ticked up 1khz, as if I had turned the knob.

I hope all this can be easily fixed with either a system restore, or, the selector knob tightening mod.

The knob does feel rather loose and slightly wobbly.

I will try and wobble the knob an see if this happens again.

I didn't have time to really look into this issue, since I was packing up my radio gear when I first noticed it.

Anyway, if anyone has any experience with this please feel free to jump in.

I wonder if there is some kind of optical sensor that is having issues?


Title: RE: fT-857d Selector Knob Malfunction
Post by: KB1VCZ on May 02, 2011, 07:29:06 AM
Well, I have done some research and found other owners with this exact issue.

This is from a review here on eHam by KI4KVS:

"The "selector" (aka "tuning") has developed a "skip" in it - the display doesn't always move the amount it should (not just on frequency, but also in the menus). There's probably some dust in the "counter wheel" assembly, but it's "sealed" against non-Yaesu intrusion."

I also found mention of this on the Yahoo users group.

I'm going to call Yaesu and see what they say.


Title: RE: fT-857d Selector Knob Malfunction
Post by: W8JX on May 02, 2011, 09:06:58 AM
The fact that tuning knob feels sloppy is not good. I fear you are going to require servicing and replacement of it. Is it a new radio or did you get it used?


Title: RE: fT-857d Selector Knob Malfunction
Post by: KB1VCZ on May 02, 2011, 10:04:42 AM
This is not the tuning knob.

It is the select knob, which by all accounts is designed to have a bit of play and wobbliness to it.

The radio is only 3 months old.

I tried to replicate the issue again and I wasn't able to, so who knows, I will just monitor it and see if it persists.

I have read that turning the knob too fast can "confuse" the optical encoder, however, I wasn't spinning it very quickly.

I have 2 posts on the Yahoo board and one reviewer here that have mentioned this issue.

After calling Yaesu they hadn't heard of this problem.

I'm still very early in the warranty cycle, so if it appears again, I'll think about boxing it up.


Title: RE: fT-857d Selector Knob Malfunction
Post by: W8JX on May 02, 2011, 11:07:09 AM
I meant encoder knob. I did not think it was main tuning encoder. The fact that is is a bit sloppy and intermittent in errors at 3 months old suggests that there is indeed a problem. I would not wait, I would return it know for repair. Better by your choice on timing than waiting to a point when it is unusable and fails at wrong time. It is not going to get better.


Title: RE: fT-857d Selector Knob Malfunction
Post by: KB1VCZ on May 02, 2011, 04:09:20 PM
Well, after 3 hours of operating time since this occurred, I have yet to to replicate the problem.

Go figure!


Title: RE: fT-857d Selector Knob Malfunction
Post by: W8JX on May 02, 2011, 04:24:46 PM
Those intermittent "gremlins" in hardware can be very unpredictable.


Title: RE: fT-857d Selector Knob Malfunction
Post by: NO2A on May 03, 2011, 12:17:50 AM
I had a peculiar thing happen with my `857 recently. The radio was on I was tuning around and had the r.i.t. on but it was cleared. Suddenly the r.i.t. readout showed an offset of exactly 1.6 khz. Hmm,that`s strange. I cleared the setting and went back to tuning around the band. Again the r.i.t. showed an offset of 1.6 khz. higher. Again I cleared it. Went back to tuning around with no problems. I haven`t noticed any other problems with it. At the time the rig had not been on long,so maybe some component wasn`t stabilized as far as temperature if that has any affect on it. The multifunction knob is wobbley but that hasn`t caused any problems with frequency readout that I know of................................ :-\


Title: RE: fT-857d Selector Knob Malfunction
Post by: KB1VCZ on May 03, 2011, 08:03:12 AM
Those intermittent "gremlins" in hardware can be very unpredictable.

Well, the only thing I can think of right now is that since this knob is a rotating pot and a push on/off "button", that perhaps something hadn't quite seated itself properly and that simply pushing the button in and out a few times rectified the problem.

And as a point of clarification, I should be more careful with my terminology.

My button doesn't wobble, there is just play in the button, which is normal and by design.

A wobble would be caused by a bent shaft, and you would notice it while turning.

I will keep and eye on things and see if the "ghost" in my FT-857 returns!!

As for the 1.6khz bug I think I might have seen something similar on the Yahoo forum, but I can't quite remeber the specifics.


Title: RE: fT-857d Selector Knob Malfunction
Post by: KG6IRW on May 03, 2011, 12:06:16 PM
What happens when you use the same control to step through your FM repeater memories?  On my older '857, I have an occasional problem with the control double-stepping.  That is, as I turn it the memories will skip through to one further down the memory stack.  Also, when tuning at 1kh step in HF mode, I also note that it will step multiple 1khz steps while I only feel a single detent on the control. 

I note this is likely an optical control and could be the root of the problem.  The shaft on mine, too, is a bit wobbly.  This isn't surprising since it also doubles as a push-switch as well.

I wonder, though, if there's really a problem with the control or elsewhere down the circuit.  I'm suspecting the optical control......still it hasn't been annoying enough to mess with it as my radio is well out of warranty at this point.  Its been a solid radio, too.

Cheers,

David


Title: RE: fT-857d Selector Knob Malfunction
Post by: KB1VCZ on May 03, 2011, 12:38:30 PM
What happens when you use the same control to step through your FM repeater memories?  On my older '857, I have an occasional problem with the control double-stepping.  That is, as I turn it the memories will skip through to one further down the memory stack.  Also, when tuning at 1kh step in HF mode, I also note that it will step multiple 1khz steps while I only feel a single detent on the control. 

I note this is likely an optical control and could be the root of the problem.  The shaft on mine, too, is a bit wobbly.  This isn't surprising since it also doubles as a push-switch as well.

I wonder, though, if there's really a problem with the control or elsewhere down the circuit.  I'm suspecting the optical control......still it hasn't been annoying enough to mess with it as my radio is well out of warranty at this point.  Its been a solid radio, too.

Cheers,

David

Well, that is somewhat similar to my experience, although I didn't try it with repeater memories.

It did happen when I was scrolling through the menu system--I turned the knob a couple clicks but the menu didn't change. Other times I would turn it one detent and it would move two menu #'s.

I will try and play around with this again tonight.


Title: RE: fT-857d Selector Knob Malfunction
Post by: KB1VCZ on May 04, 2011, 07:34:45 AM
So I learned a little something about this select knob problem yesterday.

I had turned on my radio and started tuning and everything worked fine with the select knob, so I left it on and came back about an hour later.

Upon returning I tried turning the knob but nothing happened on the LCD--I tried turning it in both directions.

So I simply pressed the knob in and out once and then I was able to change the frequency normally--no other issues occured after doing that, so I left it on and came back about 45min later and it did the same thing.

It was as if the button went to sleep or timed out, for lack of a better word. I'm going to try this test again tonight when I get home. I would be interested to know if anyone else can recreate this on their rig.


Title: RE: fT-857d Selector Knob Malfunction
Post by: W8JX on May 04, 2011, 11:42:16 AM
Have you tried doing a complete reset/reboot of radio?


Title: RE: fT-857d Selector Knob Malfunction
Post by: WE0Z on May 05, 2011, 03:58:25 AM
This is a known issue by Yaesu. I took mine apart and discovered the shaft comes has to be carefully reseated. The encoder shaft comes out when you get careless and and press too hard inward while rotating encoder. It's not hard to fix but it shouldn't be this delicate. Yaesu has a replacement shaft encode you can install.

Bob


Title: RE: fT-857d Selector Knob Malfunction
Post by: KB1VCZ on May 05, 2011, 10:41:52 AM
Well, according to the tech I talked to, Yaesu had never heard of this issue.

I'm not sure exactly what your saying from what you wrote--I can't follow your second sentence.

And I don't know why you would be pushing the knob in while rotating.

I push the knob in to make the frequency readout blink, then I can turn it in Mhz.

How can the shaft come out if you are pushing it in?





Title: RE: fT-857d Selector Knob Malfunction
Post by: KB2CPW on May 05, 2011, 05:52:37 PM
This is a known issue by Yaesu. I took mine apart and discovered the shaft comes has to be carefully reseated. The encoder shaft comes out when you get careless and and press too hard inward while rotating encoder. It's not hard to fix but it shouldn't be this delicate. Yaesu has a replacement shaft encode you can install.

Bob

  I concur,

  I've had 5 FT-857's and D models and they all did it in one form or another. The Encoder is sloppy and its a common issue. I've found that liberal use of the same knob on my TS-2000 will sometimes cause the same problem, chalk it up to low bid suppliers.. LOL


Title: RE: fT-857d Selector Knob Malfunction
Post by: KB1VCZ on May 06, 2011, 09:14:42 AM
Well, I'm not going to worry too much about it, as it doesn't seem like a big deal.

You would think the engineering and componentry behind such a high use element of the radio would be better.



Title: RE: fT-857d Selector Knob Malfunction
Post by: AB3MO on October 28, 2011, 03:29:14 PM
-   My used FT-857D (purchased in early '11, manufactured in 2006) starting showing the "flag" normally seen when the SELECT knob is pushed in allowing tuning by 1 MHz increments, but no tuning!
-   Works fine as a VHF mobile and HF backup. But would like the capability to go from 144 to 162.425MHz for NOAA WX
-   Does a field repair/fix exist for this problem? Could the average ham take the display apart and successfully repair this???
-   Want to check this out with others first before contacting Yaesu, Inc.
-   This may be why I bought a Kenwood TS-5090S rather than the corresponding Yaesu!


Title: RE: fT-857d Selector Knob Malfunction
Post by: KH6AQ on November 03, 2011, 04:35:02 AM
I've owned two FT-857 transceivers and they did not have this problem. I'd send it back to Yaesu for repair.


Title: RE: fT-857d Selector Knob Malfunction
Post by: VE6PDB on December 28, 2011, 07:58:22 PM
I have had my 857D since new and it has taken a lot of abuse while in  etc. Eventually, my selector knob became *very* loose, however it kept working, though I have noticed the skip thing from time to time, sometimes even going backwards!

I inspected the board and came to the conclusion it isn't very user-replaceable, but then I haven't done repairs of that kind in years.. umm... decades now.  However, if someone can point out the replacement part, I'd appreciate it, as when I was moving the radio from the house to Jeep tonight, the darn thing came out, shaft, knobs and all and I haven't even been able to locate the missing shaft and knobs (yet)... it's still dark out, but the snow may not help either. Thank goodness for the fancy microphone, which can do partial duty in the meantime.

The local shop said that attempting a repair may be close to as much as a new radio, but I don't need nor want a spare 857 "body" due to needing a replacement "head".

Modified Dec 29, 2011: I found a service manual online and while the board the encoder sits on is not a replacement part, there is a part number provided for the encoder in the parts list along with the OEM part.  The part specified is no longer in production or available from 3'rd party, however Yaesu is still making the radio, so there is likely an upgraded or equivalent part number. I've asked one vendor in email about that possibility.  I may have been wrong on my initial assessment, as I may not have disassembled the head far enough to truly see where the encoder was mounted.

Modified Jan 4, 2012: I disassembled the head last night and it looks like an easy repair if I can get the encoder. I haven't heard back from the parts supplier yet, so I dropped Yaesu / Vertex Standard a line themselves.

It seems the shaft is perforated from what I can see and that the hole in the head it goes through isn't tight enough to provide support, so if the shaft gets lateral pressure, it can easily snap off the small sections where the shaft is perforated, especially with the leverage provided by the length of shaft.

Modified Jan 12, 2012: Yaesu / Vertex Standard has the parts in stock, so I'm going to order a couple.  While I'm at it, I may try to "engineer" some way to fill the excess space in the faceplate around the shaft to stabilize it and reduce the chances of it having lateral loads applied to break the shaft. I obviously don't want to get it too tight so it is tough to turn either :)


Title: RE: fT-857d Selector Knob Malfunction
Post by: MM0HRL on July 30, 2015, 03:50:17 AM
It's now a VERY long time on since this topic was current but since others might yet search it out I'll add a recent experience of mine.

My FT-857d was bought new in Scotland from Jaycee in Glenrothes, in Feb 2015. Around a couple of months later I began to notice when using the rotary "select" control to shift frequency (it's extremely handy to have it set to 1kc increments in SSB operation, so I'd used it quite a bit.) that it sometimes skipped over 2kc which I put down to poor use of the rotary adjuster by me since it seemed unlikely to me that a still-new unit would have developed a fault so soon.

Well - it got worse. So that there was a place on the rotation where it always skipped up to 4kc and one or two others where a 2kc jump happened.  I was also fairly sure that when rolling through the A-Q menus that a jump would happen.

I'll stress here that I had seen photos previously of a unit were the plastic shaft had sheared off flush with the control panel, so I knew it was potentially fragile in nature. I'm naturally the sort who babies his kit, perhaps excessively so, so I knew this problem evolving wasn't down to coarse usage habits.

Took it back to the shop after I decided it was a deteriorating fault and it was away for 5 weeks because of parts needing back-ordered - so the story was from Yaesu when I asked the dealer to check on progress for me.  Which to me seemed odd when the radio is still a big seller.  This made me wonder if there'd been a sudden flush of faulty radios which had drained their spares stock.

It's back in service now and not showing signs of a recurrence, but it's made me shy of using the rotary control too much in case it goes faulty again - especially once the warranty is out.  I've  feeling it will be offloaded some time soonish.

Since writing about the 857d I'll add that I have found mine to sound really good on SSB TX with using my old Astatic Teardrop mike - which is now around 30 years old. The stock Yaesu mike supplied is a hopeless thing which under-drives the SSB transmission badly.  Elsewhere the ALC issue has been discussed so I'll not reopen that one here - however, the radio sounds so very different with the Astatic mike that I felt it worthwhile to pass that on to anyone who happens to have one in a drawer.  I had a patch lead made up so I didn't have to re-plug the mike's cable, meaning I can still use it on other radios. And used an online SDR record facility to hear my transmissions exactly as received.

Getting off-topic here so I'll finish with that.