[Elecraft] Elecraft Digest, Vol 208, Issue 2

[Alan Sewell N5NA]

I replaced my encoders in 2014 and then last Saturday I replaced the 
encoders in a friend's K3 SN 2707 I think.

In 2014 I used a solder sucker to desolder.  I now have a Hakko FR-300 
desoldering tool and used that last Saturday.  The five small pins are 
easy.  It's the two large tabs that are a bit difficult. On the bottom 
two encoders I snipped those tabs and then heated and pulled the cut off 
piece.  On the upper two encoders I desoldered the small pins and then 
rocked the encoder back and forth alternating heating the tabs.

As far as spacing the encoders I 3D printed some 1.4 mm thick x 8 mm OD 
spacers.  That worked well.  If I did it again I'd make the spacers 9 or 
10 mm OD.

In a post in May to Elecraft K3 groups.io Keith, WE6R, Elecraft K3 Tech 
posted "Our part # E640018, washer spacer E700187 or E700035 to space 
them above the board evenly."  I found a reference to E700035 in a 
manual.  It's a #4 x 3/8" nylon washer.  I couldn't find any reference 
to thickness of the washer.

73, Alan N5NA


On 2021-08-05 3:25 PM, elecraft-request at mailman.qth.net wrote:
> Message: 3
> Date: Wed, 4 Aug 2021 11:59:03 -0500
> From: Nick Kennedy<kennnick at gmail.com>
> To:elecraft at mailman.qth.net
> Subject: [Elecraft] K3 small rotary encoder replacement
> Message-ID:
> 	<CALxojYL4YsD5ucKJ2=t3GPBYC-oes_64EQ-wi0gXiUdGEuZb7A at mail.gmail.com>
> Content-Type: text/plain; charset="UTF-8"
>
> I'm in the process of replacing the four encoders to the left of the main
> VFO knob and wonder if anyone has any advice or pep talks to offer.
>
> The encoders in my summer 2008 vintage K3 degraded to the point where they
> often count backwards, making adjustment of CW speed or power out difficult.
>
> I've purchased four replacements from Elecraft and have been working up my
> courage and taking deep breaths. Getting to the board is a fairly
> complicated first phase. I had an Elecraft document on installation of an
> audio LPF on the DSP board and found it to be very useful in this process.
> Of course the original assembly manual is also useful.
>
> Now I've got the K3 apart to the point of allowing access. The upper two
> encoders have terminals located beneath an LED mounting board and are
> almost impossible to access from the top. I may stop after replacing the
> lower two, assuming I'm successful with them.
>
> My usual method involves solder wick plus flux. Sometimes I find ChipQuik
> to be very helpful in allowing me to remove a part without getting rid of
> all the solder. In this case though, using ChipQuik would require heating
> seven joints simultaneously which I haven't been able to do.
>
> There's also an issue with mounting the encoder at the correct height so
> the shaft switch can be operated. So I'll try to match the height of the
> new shaft end to that of the existing encoders.
>
> I found one website  which is somewhat helpful discussing this task:
>
> https://www.n5na.net/s9y/index.php?/archives/26-Replacing-Elecraft-K3-Push-Button-Encoders.html
>
> I'm keeping a lot of notes. Anyone planning to attempt this job is  welcome
> to them.
>
> 73
>
> Nick, WA5BDU