Garmin 430 right knob stopped working?

[thinwing]

Poor Jose ...MS,s misunderstood genius 

[jordanjms]

On 8/8/2018 at 9:48 AM, dmevans said:

 

Jose,

You were spot on with this one... My left knob (outer portion) was no longer working on my 430. Took the unit out, sprayed it with contact cleaner, and voila!! Works like it's brand new!!

Thanks for all of the help! I never would have thought of this! Saved me a little bit of money too!

I've got a very similar problem. My right outer knob will randomly stop working all together. I tried taking the knobs off and spraying contact cleaner in there, but that didn't seem to help. It sounds like you took the unit completely out. Where did you spray contact cleaner once you did that?

[Vance Harral]

15 minutes ago, jordanjms said:

I've got a very similar problem. My right outer knob will randomly stop working all together. I tried taking the knobs off and spraying contact cleaner in there, but that didn't seem to help. It sounds like you took the unit completely out. Where did you spray contact cleaner once you did that?

As mentioned previously in the thread, the knobs on a Garmin 430 are optical devices, contact cleaner cannot do anything for them.  The usual failure mode is the light source that shines through the windows of the rotary dial.  It either burns out (total failure), has reduced output (intermittent failure), or develops a weak/intermittent connection with its power source (also intermittent failure).  The fact that a previous poster "cured" their problem with contact cleaner is completely coincidental.  It's likely the act of removing the outer knob flexed the rotary dial and/or circuit board enough to make a marginal light source good enough again, for a while longer.  By all mean, try taking the knobs off and reinstalling them a few times, you might be similarly lucky.  But R&R'ing the knobs is the salient action.  Spraying contact cleaner on anything while you're doing it is no more or less effective than humming Gregorian chants.

[dmevans]

1 hour ago, Vance Harral said:

As mentioned previously in the thread, the knobs on a Garmin 430 are optical devices, contact cleaner cannot do anything for them.  The usual failure mode is the light source that shines through the windows of the rotary dial.  It either burns out (total failure), has reduced output (intermittent failure), or develops a weak/intermittent connection with its power source (also intermittent failure).  The fact that a previous poster "cured" their problem with contact cleaner is completely coincidental.  It's likely the act of removing the outer knob flexed the rotary dial and/or circuit board enough to make a marginal light source good enough again, for a while longer.  By all mean, try taking the knobs off and reinstalling them a few times, you might be similarly lucky.  But R&R'ing the knobs is the salient action.  Spraying contact cleaner on anything while you're doing it is no more or less effective than humming Gregorian chants.

Interesting. I didn't know the rotary encoders on the 430 were optical encoders.

[Mark89114]

What is the point of an optical reader switch?  Seems like a lot of complexity for a switch that simply tells the software to go up or down one position.

[carusoam]

Compared to the plastic gear driven knobs of past history...

The optical devices seem to last quite a bit longer...
 

Garmin is still in business, so we know it kinda works....

Where Narco clearly isn’t in business, they folded when my radio was in their shop to get new plastic gears...
 

BK is somewhere in the middle... their plastic gears worked several decades... but few people buy their navcoms anymore...

PP thoughts only, not a navcom tech...

Best regards,

-a-

[Jerry 5TJ]

What is this thing people keep talking about, a “knob?”

Is it, like, a backup for a touch screen? And if so why would you use a “knob” instead of voice commands?   

[Vance Harral]

On 5/21/2020 at 4:22 AM, Mark89114 said:

What is the point of an optical reader switch?  Seems like a lot of complexity for a switch that simply tells the software to go up or down one position.

Because the alternative is physical contacts that must scrape together as the switch slides from one position to another.  The mechanical wear that results is a major long-term reliability issue.  There are ways to make a physical contact knob last a long time, e.g. the knobs on a KX-155 are pretty good.  But overall, the contactless solution is more reliable.  A really relevant example of this is the optical encoder knob on the 430/530 series, vs. the physical contact buttons on that same unit for flip-flopping the NAV/COM frequencies.  Both the knob and the flip-flop buttons are used heavily, but as these units get long in the tooth, you hear vastly more problems reported with the flip-flop buttons than the knob.

If I may editorialize a bit, there's nothing "complex" about an optical encoder.  It's just a little light bulb that can or can't be "seen", based on whether something is between the bulb and the detector.  They are considerably simpler to design, manufacture, maintain, and service, than a physical switch or knob.  The on/off signal they generate is no different than the signal associated with a mechanical switch.  About the only difference between physical vs. optical switches from an interface standpoint is that in the simplest cases, the latter require 3 wires and the former only 2.  But that's hardly a big jump in complexity.  They do have failure modes, however - nothing is perfect.