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Topic: Share tips you have come across (Read 100754 times) previous topic - next topic

larryd

Did you also arrange for a power supply for the flashlight or just rely to batteries?
I just rely on the batteries.
Rechargeable AAA battery X3, about 1/2 hour at low intensity (as seen in image).
Alkaline nearby for standby.


No technical PMs.
The last thing you did is where you should start looking.

Watcher

I find that a " permanent " dc supply is increasingly  usefull on the workbench just like the mains outlets.
Just cant decide on the most useful voltage level to have around..5v, 12v...

larryd

No technical PMs.
The last thing you did is where you should start looking.

larryd

No technical PMs.
The last thing you did is where you should start looking.

TomGeorge

I find that a " permanent " dc supply is increasingly  usefull on the workbench just like the mains outlets.
Just cant decide on the most useful voltage level to have around..5v, 12v...
A good power supply for Arduino and general micro-controller needs a current limit facility.
The limit only needs to be up to 2A and adjustable.
Any higher current then another 5V outlet to the higher current devices.
Tom... :)
Everything runs on smoke, let the smoke out, it stops running....

larryd

#650
Oct 07, 2018, 11:26 pm Last Edit: Oct 07, 2018, 11:27 pm by larryd
3 quickies:









No technical PMs.
The last thing you did is where you should start looking.

datacabl

I found an excellent way to mount my Mega into a project box. Check Mouser part # 561-RV250. A small plastic standoff made by Eagle plastics. Cheap and requires no fasteners. Can be installed and removed easily. Non conductive. Also good for external boards added to the project.

larryd

No technical PMs.
The last thing you did is where you should start looking.

rmlazzari

Hi,

I'm not sure it's a real tip but maybe could be useful for somebody.

I've built a device to listen music using 18650 batteries. To charge the batteries I use a TP4056 charger manager. This TP4056, through two MOSFETs, interrupts the energy to the set player+amp when the batteires voltage gets low (I guess near 3.4v, 3.5v...), then the radio stops playing. But as the batteries are not required more, even without recharging it, it recover a little charge by itself (I believe). And the TP4056 MOSFETs turno the radio on again. And as soon as the radio is turned on, the batteries got low charge again and the TP4056 again turn it off.

This issue make the sound device become on, off, on, off several times at the end of the batteries charge. It's not awsome when it ocoours near I'm getting sleep at night. But it could be worst if the application is more important or critical than a sound gadget, so I'm bringing the solution I've got:

When the batteries turn off the set player+amp, it turns off too a flip-flop key, wich only can be re-turned on pressing a button. This flip-flop is based in a CI called 555.

Here the story of the sound device, the solution I've got from a brazilian forum and the original flip-flop scheme:

https://rmlazzari.wordpress.com/2018/01/14/para_ouvir_musica/

http://www.bowdenshobbycircuits.info/page9.htm#555-T.gif

https://www.clubedohardware.com.br/forums/topic/1290420-como-criar-chave-stand-by-liga-desliga/


Please excuse the brazilian english, reply if I got misunderstood and hope this could be useful.

WattsThat

#654
Nov 12, 2018, 01:58 am Last Edit: Nov 12, 2018, 02:06 am by WattsThat
Can be fashioned from three wooden tongue depressors, the smaller, thick ones work best. Can be found in craft stores in the wood aisle.

Cut the end of one to server as a spacer and glue together.

Hold the body of the device and pull towards yourself. Rotate and repeat.

Made and used these thirty plus years ago where we made military and very high end precision resistors.  After burn-in and whatever else the parts needed, this is how they straightened the leads prior to shipment. Works well for tinned and gold plated leads without damaging the finish. It will also remove any oxide layer if they're old, pre-lead free leads.















Vacuum tube guy in a solid state world

larryd

#655
Today at 05:52 am Last Edit: Today at 05:52 am by larryd
I often need to cut equal lengths of heat shrink tubing.

A 5/16" thread rod coupling nut, a bolt and a lock nut makes an effective cutting gauge.









No technical PMs.
The last thing you did is where you should start looking.

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