SparkFun Forums 

Where electronics enthusiasts find answers.

Search found 14 matches

 Go to advanced search

Re: Polyurethane as a conformal coating.

 by 52midnight ¦  Sun Sep 10, 2017 10:11 am ¦  Forum: Projects ¦  Topic: Polyurethane as a conformal coating. ¦  Replies: 4 ¦  Views: 747

> Liquid electrical tape

Interesting. Didn't know about it. Thanks. I'd also thought of potting compound, so there are a number of options.

Re: Polyurethane as a conformal coating.

 by 52midnight ¦  Tue Sep 05, 2017 1:20 pm ¦  Forum: Projects ¦  Topic: Polyurethane as a conformal coating. ¦  Replies: 4 ¦  Views: 747

Thanks for that - useful. Frustration eventually prompted me to finally build something I'd been putting off for yonks, a Mains Breakout Box: http://52midnight.com/MPBB/home.html This allowed me to poke around in a dried coating at mains potential to prove that whatever leakage current there might b...

Polyurethane as a conformal coating.

 by 52midnight ¦  Sun Jul 23, 2017 5:25 pm ¦  Forum: Projects ¦  Topic: Polyurethane as a conformal coating. ¦  Replies: 4 ¦  Views: 747

My first negative ion generator has been in operation for two years and has been a success. I'm now putting together a second using physically smaller capacitors and have decided to paint the cap-diode ladder with a conformal coating: http://www.vitency.com/electronics/naig.html After checking the s...

Re: Making multicell LiPo batteries out of individual cells

 by 52midnight ¦  Sat Jul 01, 2017 9:28 pm ¦  Forum: Forum ¦  Topic: Making multicell LiPo batteries out of individual cells ¦  Replies: 3 ¦  Views: 3541

Ah! Thanks, but I already have loose cells, I'm building my own charger, will include individual cell connections for charge balancing, and am STILL interested in the original question.

Making multicell LiPo batteries out of individual cells

 by 52midnight ¦  Fri Jun 30, 2017 9:59 pm ¦  Forum: Forum ¦  Topic: Making multicell LiPo batteries out of individual cells ¦  Replies: 3 ¦  Views: 3541

I take things slowly since electronics as a craft is a very detailed process. I've just bought my first brushless outrunner motor and four LiPo cells to power it (GIF ICR18650 3.7V 12000mAh) I'd like to make two 2S batteries for use in the field (one charging, the other flying). The question here is...

Re: An electrical connection to the atmosphere.

 by 52midnight ¦  Mon Jun 19, 2017 8:24 pm ¦  Forum: Forum ¦  Topic: An electrical connection to the atmosphere. ¦  Replies: 11 ¦  Views: 4567

A bit of mulling has turned up an interesting possibility. After running Version 2 of my Ion Generator on a shelf for six months, the surrounding wall became blackened around it. I live near the city centre, so car and diesel fume particles being electrically deposited - the "corollary product" of d...

Re: An electrical connection to the atmosphere.

 by 52midnight ¦  Sun Jun 18, 2017 7:54 pm ¦  Forum: Forum ¦  Topic: An electrical connection to the atmosphere. ¦  Replies: 11 ¦  Views: 4567

Hey, thanks for an unexpected and most informative reply. > The atmosphere is an extremely high impedance, low current voltage source, Very well put. > with a vertical electric field of typically 100 V/m This has always fascinated me, though the numbers I've seen vary. > and current density in the r...

Re: An electrical connection to the atmosphere.

 by 52midnight ¦  Thu Jun 15, 2017 5:29 pm ¦  Forum: Forum ¦  Topic: An electrical connection to the atmosphere. ¦  Replies: 11 ¦  Views: 4567

Thanks for the suggestions. I'm doing up some new proto PCBs which I plan to panelize, and thought I'd "fill up the holes" in the panel with something experimental. Looks like I've got the makings of a solution here.

Re: Common shaft couplings.

 by 52midnight ¦  Wed Jun 14, 2017 8:31 pm ¦  Forum: Forum ¦  Topic: Common shaft couplings. ¦  Replies: 4 ¦  Views: 3956

Thanks to all. Yes, rigid coupling is always a problem unless it's within a unit mechanical assembly. One instance of particular interest to me is coupling different e-motors (rather than glo and diesel) to common airscrews - sc. propellers - as used in RC model aircraft, although these days quadcop...

Re: An electrical connection to the atmosphere.

 by 52midnight ¦  Wed Jun 14, 2017 8:15 pm ¦  Forum: Forum ¦  Topic: An electrical connection to the atmosphere. ¦  Replies: 11 ¦  Views: 4567

I'll assume that you've practical experience with this, whereas I haven't. I'm open to using leaf, but am thinking along the lines of a small (one inch diameter) area of PCB with gold plating over copper connected to a side terminal to create an 'atmospheric ion emitter/collector'. The reason is emp...

Re: An electrical connection to the atmosphere.

 by 52midnight ¦  Wed Jun 14, 2017 1:28 pm ¦  Forum: Forum ¦  Topic: An electrical connection to the atmosphere. ¦  Replies: 11 ¦  Views: 4567

Yes, good suggestion. Probably expensive and difficult to work, but a large area of PCB with gold flash might be a cost-effective alternative.

An electrical connection to the atmosphere.

 by 52midnight ¦  Tue Jun 13, 2017 7:59 pm ¦  Forum: Forum ¦  Topic: An electrical connection to the atmosphere. ¦  Replies: 11 ¦  Views: 4567

I'm playing around with NAIGs (Negative Air Ion Generators) that use ordinary stainless steel sewing needles as ion emitters. In order to make meaningful measurements, I need an "electrical connection to the atmosphere". This is very simple in theory: all you need is a flat metal plate. Fine! But wh...

Re: Some questions met when designing PCBs

 by 52midnight ¦  Tue Jun 13, 2017 2:29 am ¦  Forum: PCB Design Questions ¦  Topic: Some questions met when designing PCBs ¦  Replies: 4 ¦  Views: 1766

As a general comment I'll start with the most obvious: textbook theory and real-world practice are quite different. If you're dealing with frequencies under - say 20MHz or microcontroller territory - then forget all about "star configuration" and the rest of the nonsense. Just run the power and grou...

Common shaft couplings.

 by 52midnight ¦  Fri Jun 02, 2017 8:27 pm ¦  Forum: Forum ¦  Topic: Common shaft couplings. ¦  Replies: 4 ¦  Views: 3956

I have a number of small electric motors and several devices I'd like to couple them to. All have varying shaft diameters and some sort of coupling is required. An easy way to do this is using heat-shrink tubing, but this is something of a kludge. This must be a common problem, yet I've not come acr...