SW electronic focus motor controller!!!

[Merlin66]

Not sure what has happened in my life!


I use many (seven at the last count!) of these motors/ controllers.
All the focusers, the etalon tuning etc.


At Xmas one of the handcontrollers failed. Changed batteries, checked connections etc. but no luck....
It's now the 22 Jan and so far I've had another two failures!!!!
I now have three controllers u/s.


I found the wiring diagram and managed to identify most of the components.
Simplistically I think the push buttons have gone to meet their maker.
(These seem to be "TL2285 OE" push buttons -https://www.digikey.com.au/catalog/en/partgroup/tl2285-and-tl4201-series/9456)


I'm definitely not an electronics guy.....but I assume these are replaceable.
Has any one else experienced similar failures????

[bojan]

Yes, they are replaceable.
How many failed? Do they work sometimes?

[Merlin66]

Bojan,
On two of them both buttons don't seem to work, on the third one button still works.
I haven't been able to find an aussie source for these buttons.

[bojan]

How about this one?
https://au.rs-online.com/web/p/push-button-switches/3543459/


also ebay:
https://www.ebay.com.au/itm/5-8-7-8-8-5mm-PCB-Tact-Push-Button-Switch-Self-Locking-Momentary-DPDT-6-Pin-DIP/123690696283?hash=item1ccc8a3e5b:g: jP0AAOSw-phciu0X

[Merlin66]

Bojan,
The 8.5mm eBay version looks like a direct equivalent.
I'll order some, see how we go.
Thanks!

[Pepper]

I replace these regularly in my pinpointer for metal detecting.
Super easy, just need some solder, iron, and some gootwick

[bojan]

So they seem to be dodgy quality? They should last couple of hundreds of thousands activations..

[Pepper]

They probably are ok Bojan. Just the pinpointer gets constantly turned on and off, and being used in dusty/muddy conditions.

[Merlin66]

Bojan,
I think the quality is probably “cost effective” for the controllers.
I haven’t heard that many others are complaining........

[doppler]

I have one with the exact same problem, out of warranty time wise but not a lot of use, so yes a quality problem me thinks.

[Merlin66]

If the microswitches I’ve ordered work out, I’ll make the “extras” available to the members.

[Rerouter]

The switches are rated for a lot of actuations, however they hate getting wet, once you have replaced the old ones, crack one open, top guess would be corrosion on the switch foil,

[Merlin66]

Ryan,
Thanks, but I don’t think my controllers have ever been outside the office.
Certainly not exposed to rain or heavy dust etc.
I’ll definitely pull one apart when the others arrive.

[Merlin66]

Update:
I ordered "drop in replacement" switches from eBay, and got some desoldering braid.
The switches arrived yesterday, and within 30 mins today I had all three hand controllers repaired and fully functional!!!
Total cost $12 - that works out at $4 per unit to repair.
Well worth considering.

[iborg]

Hi Merlin

An idea to consider, give them spray with silicone lubricant. Might lube the contacts and at least limit corrosion.

Philip

[Merlin66]

Philip,
I don't think the failure were corrosion.
They just basically stopped!
Replacing the switches is the way to go..worked 100%

[iborg]

Hi

At least they sound easy to replace.

Good luck with the new ones.

Philip

[Merlin66]

Philip,
So far so good.