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THE AM BULLETIN BOARD => Technical Forum => Topic started by: Opcom on April 08, 2023, 11:12:01 PM



Title: ham estate mystery item
Post by: Opcom on April 08, 2023, 11:12:01 PM
This ham had many, many interesting things. Here is something new to me for sure. These were in an organizing bin with a couple of CL-5M5 photocells. -which seem like regular type photocells/photoresistors and not really related to the parts in question.

These are about 1.2" diameter, and have 4 short pins out what I presume is the backside. The other side is slightly domed in appearance. Inside these, there seems to be a liquid, somewhat viscous, and dark-colored like motor oil or light molasses. I can't see where the pins go. As the device is rotated like a wheel, the liquid is free to stay in the lower half.

The number on all of them is 74821 -01
Any ideas what these are?


Title: Re: ham estate mystery item
Post by: W1RKW on April 09, 2023, 08:30:51 AM
up/down position sensor?


Title: Re: ham estate mystery item
Post by: W3SLK on April 09, 2023, 08:41:37 AM
W1RKW said:
Quote
up/down position sensor?

I was going to say something like a mercoid switch.


Title: Re: ham estate mystery item
Post by: KD1SH on April 09, 2023, 10:15:54 AM
Curious - have you tried taking resistance readings across the contacts, and if so, do they change at all with a change in physical orientation?
And, just a shot-in-the-dark: since these mystery devices were in a bin with photocells, and they have a transparent cover, do you think they might actually be photo-sensitive?
I would actually have expected the contact pins to be on the other side if that were the case, but it's just a thought.


Title: Re: ham estate mystery item
Post by: wa2tak on April 09, 2023, 04:09:27 PM
Might it be a lightning surge protector...

https://www.cheapham.com/ldg-sp-200-lightning-surge-protector-replacement-gdt/


Title: Re: ham estate mystery item
Post by: K8DI on April 10, 2023, 07:27:46 AM
Might it be a lightning surge protector...

https://www.cheapham.com/ldg-sp-200-lightning-surge-protector-replacement-gdt/
Those are much smaller than the 1.2” diameter OP listed. 
 https://www.littelfuse.com/~/media/electronics/datasheets/gas_discharge_tubes/littelfuse_gdt_cg_cg2_datasheet.pdf.pdf (https://www.littelfuse.com/~/media/electronics/datasheets/gas_discharge_tubes/littelfuse_gdt_cg_cg2_datasheet.pdf.pdf)

My guess is some form of position sensor.  Does the bit inside that looks metallic move?

Ed


Title: Re: ham estate mystery item
Post by: Opcom on April 14, 2023, 09:14:54 PM
Only the liquid moves and there does not seem to be anything else inside. It is probably not a pellet type surge suppressor at least not the composite disc or pellet type. I did not check resistance, but will do next time I am there. I wonder if it could be automotive as the gentleman did a lot of work on his own cars, but this was in an otherwise electronics bin organizer.


Title: Re: ham estate mystery item
Post by: WBear2GCR on April 23, 2023, 09:42:03 AM

I believe that is a rare "fitzwaddit"... an integral, but poorly understood and quantum operating device used primarily in the Flux Capacitor assembly, as first found in Roswell...


Title: Re: ham estate mystery item
Post by: KD6VXI on April 23, 2023, 04:27:40 PM
My grandfather referred to such things as dingwatchits, gizzyflobs and other such terms.

Genuine West Texas frontier jibberish.


--Shane
WP2ASS / ex KD6VXI


Title: Re: ham estate mystery item
Post by: Opcom on April 24, 2023, 01:54:16 AM
A Dallas TX mechanic years ago called odd looking things: 'that Hooter-McGruder deal'.


Title: Re: ham estate mystery item
Post by: Jim/WA2MER on April 24, 2023, 06:57:49 AM
Those are framistats. Their sole purpose is to cause a bunch of old guys to go on about them for days on end. Apparently those are still in good working order.  ;D


Title: Re: ham estate mystery item
Post by: KD6VXI on April 25, 2023, 05:46:59 AM
Lol.  That reminds me of more West Texas Jibberish.

Grandpa, what's this?  I ask, pointing at something under the hood of the car.

Grandpa, "That's designed to make little boys ask questions.   Works, don't it!".

Of course, he would give me the full rundown after he got his five chuckles in.

--Shane
WP2ASS / ex KD6VXI


Title: Re: ham estate mystery item
Post by: RolandSWL on April 26, 2023, 08:59:57 AM
No. Sorry. Framistats had a left hand thread. This is a sub assembly from a Shpitzen-shparken suppressor.


Title: Re: ham estate mystery item
Post by: W7TFO on April 26, 2023, 11:22:30 AM
Alien technology.


Title: Re: ham estate mystery item
Post by: KD6VXI on April 26, 2023, 11:47:09 AM
OK, I did find out what it is, all BS aside.


It's a one of those.


--Shane
WP2ASS / ex KD6VXI


Title: Re: ham estate mystery item
Post by: Opcom on May 01, 2023, 12:12:18 AM
up/down position sensor?

We have a winner!

The mysterious fluid is conductive. When it is touching two pin elements, the resistance between them is about 1-2K Ohms. When it is not touching, the resistance is much higher, about 20-30K. Perhaps that high resistance is a residual conduction from a very small amount of the fluid coating ther inside. Perhaps the conductive fluid is an alternative to mercury.

If the device were mounted on a slowly rotating hub, it could be used to detect approximate relative phase and the direction of rotation. I did not have enough fingers to try to see what happens when three terminals touch the fluid.


Title: Re: ham estate mystery item
Post by: DMOD on May 01, 2023, 12:48:57 AM
up/down position sensor?

We have a winner!

The mysterious fluid is conductive. When it is touching two pin elements, the resistance between them is about 1-2K Ohms. When it is not touching, the resistance is much higher, about 20-30K. Perhaps that high resistance is a residual conduction from a very small amount of the fluid coating ther inside. Perhaps the conductive fluid is an alternative to mercury.

If the device were mounted on a slowly rotating hub, it could be used to detect approximate relative phase and the direction of rotation. I did not have enough fingers to try to see what happens when three terminals touch the fluid.


OK, it's so a 4-pole Shpitzen-shparken position sensor. ;D


Title: Re: ham estate mystery item
Post by: Opcom on May 03, 2023, 01:42:37 AM
up/down position sensor?

We have a winner!

The mysterious fluid is conductive. When it is touching two pin elements, the resistance between them is about 1-2K Ohms. When it is not touching, the resistance is much higher, about 20-30K. Perhaps that high resistance is a residual conduction from a very small amount of the fluid coating ther inside. Perhaps the conductive fluid is an alternative to mercury.

If the device were mounted on a slowly rotating hub, it could be used to detect approximate relative phase and the direction of rotation. I did not have enough fingers to try to see what happens when three terminals touch the fluid.


OK, it's so a 4-pole Shpitzen-shparken position sensor. ;D

And so it shall be advertised in that manner at the upcoming vintage ham/maker/science components 'estate sale'.


Title: Re: ham estate mystery item
Post by: RolandSWL on May 04, 2023, 12:58:20 PM
O.K., But you must include the product safety warning with it:
ACHTUNG!
ALLES TURISTEN UND NONTEKNISCHEN LOOKENSPEEPERS!
DAS RFMASCHINE IST NICHT FÜR DER GEFINGERPOKEN UND MITTENGRABEN! ODERWISE IST EASY TO SCHNAPPEN DER SPRINGENWERK, BLOWENFUSEN UND POPPENCORKEN MIT SPITZENSPARKEN.
IST NICHT FÜR GEWERKEN BEI DUMMKOPFEN. DER RUBBERNECKEN SIGHTSEEREN KEEPEN DAS COTTONPICKEN HÄNDER IN DAS POCKETS MUSS.
ZO RELAXEN UND WATSCHEN DER BLINKENLICHTEN.



Title: Re: ham estate mystery item
Post by: Opcom on April 24, 2024, 03:23:22 PM
It is finally confirmed as to what this item is. It's an Electrolytic Tilt Sensor, not a switch, but a sensor in that the resistive fluid surrounds more or less of each pin, depending upon the angle deviation from 'normal'. When perfectly upright, the resistances between adjacent pins are all equal, as are equal the diagonal corner to corner resistances.

The amount of variance in resistances measured in the upright position is very small but this is calibrated for in the electronics part of the sensor at the factory so they are very accurate.

Some uses are for measuring tilt on scissor lifts, laser levels, and other things which must be kept upright or at a prescribed angle. Fredericks Company is one manufacturer of the devices.
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