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Voltage reduction

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  • Member since
    December 2009
  • 159 posts
Posted by mkepler954 on Friday, March 17, 2023 9:26 PM

I found several dimmers in my spares box and hooked them up.  Worked perfectly! 

Thanks for all your suggestions.

  • Member since
    February 2007
  • From: Christiana, TN
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Posted by CSX Robert on Friday, March 17, 2023 3:35 PM

mkepler954

How do I reduce a 6v DC source down to 4.5v?

 

As mentioned, there are a lotof ways to do it.  Which is best will be determined by what you are powering and how stable you 6 volt source is.

  • Member since
    January 2015
  • From: Southern California
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Posted by Lone Wolf and Santa Fe on Thursday, March 16, 2023 8:19 PM

Look through all of your old wall warts and find one with a 4.5 VDC output, or buy one.

There are also wall warts that are variable with the flip of a switch.

I'm not endorsing this one. It was just the first that popped up in a search but it will work for you. As you can see it does 4.5 volts as well as other low voltages.

https://www.ebay.com/itm/124160879499?chn=ps&_trkparms=ispr%3D1&amdata=enc%3A1sbK-tJrsS_6MJXORA226NQ4&norover=1&mkevt=1&mkrid=711-117182-37290-0&mkcid=2&mkscid=101&itemid=124160879499&targetid=1584571731043&device=c&mktype=&googleloc=9031476&poi=&campaignid=15275224983&mkgroupid=131097072938&rlsatarget=pla-1584571731043&abcId=9300697&merchantid=116326461&gclid=CjwKCAjw_MqgBhAGEiwAnYOAer5uAk6gddCBNUQuL27dB1BKy0Wo3dF0nu1o90Pp2heGMJ5qbqqNBxoCoDcQAvD_BwE

Modeling a fictional version of California set in the 1990s Lone Wolf and Santa Fe Railroad
  • Member since
    April 2021
  • From: saskabush
  • 127 posts
Posted by wvgca on Thursday, March 16, 2023 7:40 AM

lots of good suggestions .. diode is robably the lowest cost .. depends on what your current draw is

  • Member since
    July 2009
  • From: lavale, md
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Posted by gregc on Thursday, March 16, 2023 5:15 AM

greg - Philadelphia & Reading / Reading

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    April 2004
  • From: Ontario Canada
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Posted by Mark R. on Wednesday, March 15, 2023 10:40 PM

The simplest method to drop voltage would be to just install a diode(s) in series with the power line. Each diode will drop 0.7 volts. Use diodes with sufficient amperage rating for what you are drawing current wise on the line.

Mark.

¡ uʍop ǝpısdn sı ǝɹnʇɐuƃıs ʎɯ 'dlǝɥ

  • Member since
    December 2004
  • From: Bedford, MA, USA
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Posted by MisterBeasley on Wednesday, March 15, 2023 8:26 PM

If you have just one device, figure out what it needs and use Ohm's Law to determine the needed resistance.  If there's more than one device needing 4.5 volts, get a 4.5 volt supply and save yourself a lot of trouble.

It takes an iron man to play with a toy iron horse. 

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    February 2018
  • From: Flyover Country
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Posted by York1 on Wednesday, March 15, 2023 8:25 PM

I'll second Henry's suggestion.  For five or six dollars, you can get a buck converter that allows you to connect wires without soldering, and they're adjustable if you ever want to change to a different voltage.

York1 John       

  • Member since
    December 2015
  • From: Shenandoah Valley
  • 9,094 posts
Posted by BigDaddy on Wednesday, March 15, 2023 8:13 PM

There are also "Buck" regulators.  Not sure why they are called Buck, but they used to be a lot cheaper.  The digital readout is useful 

https://tinyurl.com/2obepc66

Henry

COB Potomac & Northern

Shenandoah Valley

  • Member since
    December 2016
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Posted by TrainzLuvr on Wednesday, March 15, 2023 8:07 PM

I would consider the amperage needed first, and not bother with resistors because they will be heating up if too much current is going through them.

Look up Fixed Voltage Regulator, in the likes of LM78xx series, with LM7805 giving you around 5V stable output. They are cheap and ubiquitous.

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    March 2011
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Posted by NVSRR on Wednesday, March 15, 2023 6:41 PM

using ohm's law will give you the propper size resistor for your application.  there is another formula that will give you the watt size of that resistor

A pessimist sees a dark tunnel

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Voltage reduction
Posted by mkepler954 on Wednesday, March 15, 2023 5:52 PM

How do I reduce a 6v DC source down to 4.5v?

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