KX3 VFO B skipping

[kc1fdg]

Hi all,

Just received a used KX3 today and found that VFO B is skipping. Lets say the top number is rotation out of 9 and bottom number is actual sensed position, it kinda does this>

123456789
121233323

And so on and so forth.

Is there a way to clean these out or replace them?

As a point of interest, it seems to go away if you put a little force on the knob perpendicular to the axis of rotation.

[Don Wilhelm-4]

It is most likely that the encoder must be replaced to correct that
behavior.

The VFO B encoder is a thru-hole part and can be replaced if you have
good de-soldering tools and work very carefully so you do not damage
anything else around it or damage the board or the SMD parts that are in
close proximity to the encoder solder pads.
Reverse the steps in the assembly manual to tell you how to get to the
encoder and front panel board.  Make careful note of the screw size and
length in each place you remove a screw.

If doing that gives you pause, then let the techs at Elecraft handle it
for you - it will be worth the price.  Contact support to initiate the
RSA process.
If you just want to purchase the encoder and do it yourself, you can
contact [hidden email] directly.

73,
Don W3FPR

On 4/7/2016 12:52 AM, kc1fdg wrote:
> Hi all,
>
> Just received a used KX3 today and found that VFO B is skipping. Lets say
> the top number is rotation out of 9 and bottom number is actual sensed
> position, it kinda does this>
>
>

______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to [hidden email]

[Tim Henrion]

Hi Don,
Do you have a manufacturer/part number for the encoders used in the KX3? That information doesn’t appear to be in the schematics. Based on personal preference, I’d like to replace at least some of the encoders in my unit with alternatives that that have detents as well as less mechanical play in the shaft.

Thanks,
Tim, KC1EOQ

> On Apr 7, 2016, at 9:11 AM, Don Wilhelm <[hidden email]> wrote:
>
> It is most likely that the encoder must be replaced to correct that behavior.
>
> The VFO B encoder is a thru-hole part and can be replaced if you have good de-soldering tools and work very carefully so you do not damage anything else around it or damage the board or the SMD parts that are in close proximity to the encoder solder pads.
> Reverse the steps in the assembly manual to tell you how to get to the encoder and front panel board.  Make careful note of the screw size and length in each place you remove a screw.
>
> If doing that gives you pause, then let the techs at Elecraft handle it for you - it will be worth the price.  Contact support to initiate the RSA process.
> If you just want to purchase the encoder and do it yourself, you can contact [hidden email] directly.
>
> 73,
> Don W3FPR
>
> On 4/7/2016 12:52 AM, kc1fdg wrote:
>> Hi all,
>>
>> Just received a used KX3 today and found that VFO B is skipping. Lets say
>> the top number is rotation out of 9 and bottom number is actual sensed
>> position, it kinda does this>
>>
>>
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to [hidden email]

______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to [hidden email]

[Don Wilhelm-4]

Tim,

Sorry, but I do not have that information.  You can get the replacements
from Elecraft parts, but as far as alternatives (detented encoders), I
have no idea.

Since the controls are encoders rather than potentiometers, I think
using something detented would not be the best thing.  The detent is
mechanical and is not likely to line up with the firmware decoding of
the encoder rotation.

Of course, I am thinking of a 'center detent', but if you are thinking
of those awful encoders that have a detent at each movement of the knob,
count me out, those are terrible to use IMHO.

You can get stock replacements for the encoders from Elecraft.

73,
Don W3FPR

On 4/8/2016 7:01 PM, Tim Henrion wrote:
> Hi Don,
> Do you have a manufacturer/part number for the encoders used in the KX3? That information doesn’t appear to be in the schematics. Based on personal preference, I’d like to replace at least some of the encoders in my unit with alternatives that that have detents as well as less mechanical play in the shaft.
>
>

______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to [hidden email]