Questions tagged [contact]
82 questions
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4 answers
Contact a very small area (impedance matched)
In my current project, I want to apply a voltage to a capacitor (top electrode on a thin film heterostructure) very rapidly. Since capacitors have their own charging rate \$(\tau = R \cdot t = R \cdot \epsilon_r \cdot \epsilon_0 \cdot\frac{A}{d} )\$…
Marv_92
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Is it safe to clean contacts with an eraser?
Today, while I was cleaning a RAM module, I was thinking about this.
An eraser is really a easy way to clean gold/copper contacts in such modules.
And it is really tempting to do so.
I did it a few times with RAMs, network cards, graphic cards and…
Ismael Miguel
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9
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4 answers
Contacts corroding - why?
These solder joints on the connector look strange to me (tarnished purple).
In a more "advanced" state, they end up looking like this:
In the last image you can see, it even "ate" the plating on the mating surface of the connector, while two of…
imp
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9
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2 answers
Wardrobe Under Shelf LED lighting that can be moved about freely
Hi I have seen a design for some LED strip lighting that is very simple to understand but am really looking for the various components so that I can replicate it. It seems that I don't know the right keywords for a successful google search so if you…
RoshDamunki
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6
votes
4 answers
Spring-loaded pins for power transfer
I am trying to build an automated battery swap mechanism for drones.
What I currently have in mind is a battery housing sitting on the drone which has electrical contacts on the inside, and a Li-po battery inside a third printed enclosure, which has…
Dev Rajput
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6
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3 answers
What is the purpose of the spring used in point-contact transistor?
Below on the left side of the illustration there is a point-contact transistor which is the first transistor invented in 1947:
It seems the symbol of BJT actually comes from this point-contact transistor even though they operate very different…
user16307
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Why are contacts missing on some of these M.2 modules?
I want to replace a preinstalled Qualcomm Atheros WiFi/Bluetooth M.2 2230 card on my motherboard (ASUS Maximus VIII Impact) with another that has better driver support. This is what the card I want to replace looks like.
As you can see, its edge…
Wandering Fool
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3 answers
What is initial contact resistance in relays?
I am reading datasheet of a relay. I see a term, initial contact resistance in relays. What is the definition of this parameter? Thanks.
user15847
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4
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1 answer
Molex PicoBlade current rating confusing
It seems there are confliction in specifications of PicoBlade for current rating.
From the MolexPicoBlade Connector System datasheet,
I assume that the current values in table is per circuit value.
So, with 26AWG 2-circuit, I can transfer 2.5A for…
slyx
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2 answers
What is the name of this battery contact type?
In the following video (timestamped): https://youtu.be/rylbFnTgFI8?t=107, you can very briefly see a C shaped battery contact within the "cap" of the battery kit.
The benefit of this specific contact is that, it is both spring-y and allows…
ZeroZ30o
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4
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1 answer
What are these battery power connectors called?
I'm trying to source some battery contact connectors for sliding straight metal strips into. They're the sort of thing that are used in power tool batteries, but I want to use them for a different project.
Can anyone tell me what these are called…
DrAl
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1 answer
How can a marginal connection become "good" by just applying a little more voltage?
"On the side" I do a fair amount of repair work to guitar gear -- Amplifiers, pedals, guitars, etc...
I've had a similar symptom occur on different repairs, and found the same root cause for each. But the physics behind how it's possible is…
Kyle B
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Which surface finish for edge connector plating to increase number of mating cycles with sliding spring contact?
I'd wish to insert a small 12x33mm PCB into a USB slot multiple times a day. Because of that high number of expected mating cycles, the surface finish of the edge connector should be chosen wisely.
The PCB will draw 2 microamps of current in…
Pro Backup
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Does the dropper between the catenary wire and contact wire carry current?
From my observations, droppers are of metal and they do not have any insulation from the catenary wire or from the contact wire.
The catenary and contact both carry the same phase and voltage so any voltage drop that occurs in the contact wire can…
3
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1 answer
Is WD40 good for restoring corroded electrical contacts?
One of the pins inside my iPhone has corroded my dad said to put a little bit of WD40 on the contacts his an engineer but to me oil on electrical contacts sounds wrong my friend said use alcohol too, who should I listen to?
ben
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