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61  Using Arduino / LEDs and Multiplexing / Re: Way to cheat 74HC595 maximum continuous operating current? on: August 03, 2014, 10:01:21 pm
Uln2003 in combo with the 595 will result in a lot less wires than using bjts.
62  Using Arduino / Sensors / Re: Protecting the AD pins on: August 03, 2014, 09:56:57 pm
And r3 is there to limit current to the ad pin if all else fails.

Well it's then much too low a value as if and when the ADC internal clamping diodes conduct they are rated at less then a milliamp before damage can result.

There is no such protection that covers 'if all else fails'.  smiley-wink

A 1ma blowable fuse? smiley
63  Using Arduino / Sensors / Re: Protecting the AD pins on: August 03, 2014, 09:03:58 pm
I guess you can use the tvs either end?   Eg 5v on the input to arduino, 16v on the input/resistor divider.


Yes sorry I'm often mixing zener with schottky,  they look similar to me, what's the purpose of the schottkys? I'm curious
64  Using Arduino / Sensors / Re: Protecting the AD pins on: August 03, 2014, 08:26:31 pm
So you have  a resistor divider then a zener to clamp down...


The zener on the vcc line serves what purpose? ... zeners are slow which could be why you keep blowing adc ports ?  Buy a coupke TVS diodes instead to protect the arduino.  clamp it  to say 16v on the input making sure the resist divider does it job
65  Using Arduino / General Electronics / Re: 220VAC to 12DC on: August 03, 2014, 03:47:26 pm
NO NO NO

Do NOT buy that module!
It have almost NO INSULATION gap!

From another forum http://sv.tinypic.com/view.php?pic=zl3y2s&s=8#.U96TnCiChN4

Rat97, remember my retire

OK AWOL I give up but you forgot Beatles and Richard Branson. Let's stop here, this is rat97's tread.

Pelle

Interesting, i though that thoose are the modules what are inside adapters....

They are!   And they are the better of the el cheapo ones too which are capacitor fed. My rule for using cheap power supplies is simple don't use them for anything you'll need to touch or handle, treat them as works of art, always disconnect power before touching what the power supply is powering...

The one you posted should be fine because it's isolated with the transformer if anything fails...

 r
66  Using Arduino / General Electronics / Re: Extending battery life on: August 03, 2014, 03:37:35 pm
http://www.ebay.com.au/itm/Rechargeable-Ni-MH-Battery-Pack-7-2V-2000mAh-Tamiya-RC-Car-Truck-Truggy-RC-/151303315803

Aussie dealers are the worst on ebay lol
67  Using Arduino / General Electronics / Re: How screwed am I? (Failed solder attempt) on: August 03, 2014, 03:28:51 pm
Oh wow, that soldering job brought back memories smiley

When you can, dump it and go for a temperature controlled station with esd protection.  Those header pins  smiley-eek-blue  if you wanted to, scrape off the silk screen to get at the pcb tracks and if you really wanted to use jumper wire to repair them, it's time consuming though.

68  Using Arduino / General Electronics / Re: Cheap Soldering Iron Problems on: August 03, 2014, 03:20:40 pm
[quote auwantr=dave-in-nj link=topic=258653.msg1828648#msg1828648 date=1407077857]
If my soldering station fails how do I repair it   smiley-eek

depends on how if fails.  if the dog chewed the cord, just replace the cord.
if the tip is corded and not making contact, clean the contacts
if the fuse blew.... I guess we could do this all day.
many irons are just a transformer, a heat sensor and a triac.   find out what is not working and you will probably figure out how to fix it.


As in I can't repair it because I need a soldering iron!   Obviously what you suggested are the first things I'd check...


take a breath,  facts, we can only deal with facts.  'broken' is not a description.  "i'd check" if a future tense of a verb.

voltage meter.  has no operational requirement that includes a working soldering iron. use it, find where the power stops.

since a soldering iron is a cord, a handle and a heating element, there is little to stop it from working.  also, most are made of steel so rusting occurs.  cleaning is required. 

make, model, photo, findings of testing....   


[/quote]


Huh? You want facts for a non broken soldering station?
69  Using Arduino / General Electronics / Re: 220VAC to 12DC on: August 03, 2014, 09:18:35 am
Then buy a small 500ma usb phone charger! 

Feed the 5v into the 5v (I think vin goes to the regulator) of your arduino.

70  Using Arduino / General Electronics / Re: 220VAC to 12DC on: August 03, 2014, 08:46:30 am
Smaller?  There are compact usb power supllies ... 9v a must?
71  Community / Website and Forum / Re: Too much spam ! on: August 03, 2014, 08:40:31 am
On some forums you can set it up so your first post is shown once approved by mod...
72  Using Arduino / General Electronics / Re: Cheap Soldering Iron Problems on: August 03, 2014, 02:23:06 am
If my soldering station fails how do I repair it   smiley-eek

depends on how if fails.  if the dog chewed the cord, just replace the cord.

if the tip is corded and not making contact, clean the contacts

if the fuse blew.... I guess we could do this all day.

many irons are just a transformer, a heat sensor and a triac.   find out what is not working and you will probably figure out how to fix it.










As in I can't repair it becsuse I need a soldering iron!   Obviously what you suggested are the first things I'd check...

73  Using Arduino / Project Guidance / Re: board with GPS on: August 02, 2014, 09:47:27 pm
Your cat will  hide where there's no signal smiley
74  Using Arduino / General Electronics / Re: How to filter power supply for NeoPixel circuit on: August 02, 2014, 09:40:24 pm
 What's the power source?

A couple of large caps to deal with the power supply, then feed that to the 7805?

Hard to imagine without a circuit
75  Using Arduino / General Electronics / Re: Cheap Soldering Iron Problems on: August 02, 2014, 09:04:40 pm
If my soldering station fails how do I repair it   smiley-eek
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