[Elecraft] K3 Headphone jack/front panel gap

[KM5Q]

Ron,

Thank you for the detailed reply. I have shortened your response  
below, and inserted my comments.

Ron D'Eau Claire wrote:
Tue, 29 Apr 2008 13:28:14 -0700

> I've only received sporadic reports of this happening, and *nothing*  
> after
> suggesting checking the fit of the mic connector, which led me to  
> believe
> the problem was fixed as suggested....

My mic connector does clear the hole, as in Fig. 37.

> ... Among the returns they have noticed several that did not have  
> the split ring
> lock washer between the standoff and the pc board as shown in Figure  
> 34 of
> the assembly manual. Instead the builder put the washer under the  
> head of
> the screw because that’s where one might expect to put a lock  
> washer, but
> that is *not* where it goes. ...

I'm certain I did it as described.

> In this case it is part of the total spacer
> provided by the standoff and must go between the standoff and the pc  
> board.
> That mistake actually helps the PHONES washer fit more tightly by  
> moving
> everything forward toward the sheet metal, but can result in a  
> skewed VFO A
> shaft since the connector 'bottoms out' in the jack on the front  
> panel PC
> board before it sits squarely behind the front panel.

In that case, I suppose I would have seen the threaded shaft draw  
outward as I snugged the nut. I used a box-end wrench and watched, and  
didn't see that happening. I think the toothed lockwasher on the  
inside crushed more on one side. Since I had 6" wrench leverage, I  
followed temptation and made it pretty tight, maybe more than  
intended? - but not extreme. I do have some finesse. I suppose I could  
try tightening it more, to see if it straightens out.

> Adding the nut inside
> the front panel will move the VFO A encoder back and solve that  
> problem, but
> it can cause fit issues in the future as you add options.
>
> Another problem that mistake causes are occasional broken LCD glass  
> because
> the display is moved forward with the front panel board where the  
> screws
> holding the LCD cover can strike it.
>
> So far, they have found they can fix loose PHONES jack washers and  
> crooked
> VFO A encoders by tightening the nuts sufficiently. As one builder
> mentioned, the knurled nut defies too much tightening with a tool  
> unless one
> risks scratching the front panel. What the folks in Aptos have done  
> is to
> squeeze the front panel sheet metal back against the PC boards in  
> one hand,
> pressing *between* the jack and the red and yellow LEDs just above  
> it (but
> not ON the LEDs) with a thumb while supporting the PC boards with  
> their
> fingers from behind. That flexes the sheet metal just slightly but  
> enough to
> allow them to tighten the PHONES knurled nut with the fingers of the  
> other
> hand to trap the washer securely. So far, that has cured all the loose
> washers they have encountered assembling rigs.

That's what I did when I assembled it, since I didn't think just  
finger-tight would do. I got it tighter that way, but still, it  
loosened as soon as I plugged headphones in a couple times.

> They also reported getting a few K3s back with complaints about a  
> crooked
> VFO A encoder that was fixed simply by tightening the nut against  
> the front
> panel. It was finger tight, but not tight enough. A little extra  
> leverage on
> the nut straightened up the shaft.

See above. Mine IS pretty tight.

> Of course, both of those "fixes" can cause serious damage if the  
> front panel
> is not properly spaced from the front panel board using the 5/16"  
> standoffs
> and split lock washers as shown in the manual.

I guess I'm safe there.

> An obvious question is "how tight is too tight" so that it might break
> something. I have assembled two front panels, and both times nominal
> pressure with pliers (or a socket wrench held in my hand - no handle
> attached) was plenty. But two is a tiny sample. It would be good to  
> hear
> from those who have the "loose Phones washer" and "crooked VFO A  
> encoder"
> problems and whether any of the above helped, should you be inclined  
> to take
> another look.
>
> Feel free to drop me a note if you're experiencing these problems  
> and let me
> know if the above help.
>
> Ron

If I can find some fix for the loose PHONES jack, I'll be happy to  
leave the encoder shaft as it is, unless you suggest I tighten it a  
bit more (trusting my good judgement) but now that I recall from the  
photo how slim the lock washers are, I'm more inclined to leave well  
enough alone.

Thanks!
Windy