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Special Precision TRIMPOT Log 250K Ohm Solder Tags (NEW Old Stock)

$1.50
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HISTORY:

Sustainability is the name of the game! Anything (that has been tested and still functioning properly) should be repurposed creating saving in wasted Ee and reducing the poisoning our environment when items are buried in the earth at the local tip needlessly.

 

Never heard of Ee? It is a concept that creates a measurement of ALL things (not just electronics) that humans have made and the energy used in obtaining the raw material, processing the materials right through to a finished product and even should include the shipping of the item to the distributors/retailers.

If you would like to know more about Ee values, please take a look HERE

 

Ex workshop spare parts and small manufacturing stock - originally designed into some servo control products, position sensor.

BRAND NEW

Old Stock

ALL devices have been sourced through reputable local distributors such as RS Electronics, Farnell, WES and Rockby (Victoria)

 

This is no ordinary trim pot!

It is not just about the Gold plated legs (and I can see the plating extends inside to the wiper as well) but also precision tolerance AND these can be "group stacked"

What does "group stacking" mean?

In the centre, there is a sloted hole. By fitting a small plastic shaft into this hole you can mechanically control another (or more) trimmer pots at the same time, creating what is effectively a dual gang trimmer pot (or even tri-gang) with different trimmer values on each gang!

Ah (I hear you wondering), where do I get those small plastic shafts?

I found some! Take a look HERE

But wait there's more!

This trimpot has no "stops" i.e continuous rotation, perfect for position sensing

 

UNMARKED MANUFACTURER - Trimpot

NOTE: I am "pretty" sure these are actually BOURNS (USA) components

Made in Mexico

Model: Not sure! We ordered these as a "special" and I cannot see any references to this type of trimpot in the BOURNS contemporary catalogues.

Body colour: Black Plastic with White centre hole area

ID MARKINGS ON THE BODY:

Side (Light Grey printed):

U-250K-OHM

MEXICO D4 E4 or D5 (various batches)

There are no further printed or stamped identifications on the body at all

Track resistance: 250K Ohm

Taper: Log (Because of the strange prefix, not A or B, in the part number I checked the taper - from across the entire track until around 50% it is linear in change and then for the remaining 50% of travel the trimpot rapidly drops towards zero i.e it is not linear.

Tolerance: +/- 5% or less!

Single rotation to move across the whole track

Continuous turn (no stop)

Slot centre adjustment from either side

Power rating: 500mW

Mounting: Vertical PCB using 12mm square pins (similar to wire-wrap posts)

 

DIMENSIONS:

15.85mm wide x 16.75mm height x 10.2mm deep

Gold plated solder tags (NOT PCB PINS)

5.5mm pin spacing between any two of the three solder tags

Centre adjustment hole measures 3.5mm diameter (slotted)

SPECIAL NOTE:

Mounting needs to be improvised. Whereas my other special trimpots are supported by the strong PCB pins, this trimpot has solder tags only.

Every trimpot has an extremely small hole through the body in each corner, this hole is EXTREMELY small diameter. I cannot get a very accurate reading with my micrometer but it looks to be around 1mm diameter.

 

COSMETIC CONDITION:

NEW Old Stock (in original packaging with the solder tags inserted into foam for protection)

NO body damage

NO solder tag damage (straight, clean and not crushed)

 

TEST NOTES:

I measured quite a number of these trim pots to remind myself of their basic characteristics (it was a long time ago that we purchased and used these!)

Tested 75% of these trimmers (and then grew tired of it!) and ALWAYS the total track resistance tolerance never exceeded 5% variation.

Continuous rotation, there is no stop point. Wiper resistance SMOOTHLY (but in a log taper fashion) moves from zero to the full track resistance and then if rotation is continued, wiper resistance drops right back to zero again.

I am 95% sure that these are based on a plastic conductive/cermet track for high accuracy and reliablity.

 

*** Where the photograph shows multiple components, this advertisement is for ONE component not all that are shown!

NEW Old Stock