DC - DC 12v to 5v Converters?

[Dougal]

Just wondering if anyone has any good recommendations for these? I've tried several, and they've all caused interference on both marine band VHF and stereo FM radio bands. They're extremely useful little gizmos but i would like to loose the interference.

 

[GHA]

I use quite a few adjustable ones, if interference is bad then sticking random capacitors on the in and out seems to clean it up enough.


RTL usb dongles can make a cheap spectrum analyzer to see what's really going on -

https://www.rtl-sdr.com/spektrum-new-rtl-sdr-spectrum-analyzer-software/

 

[Dougal]

I use quite a few adjustable ones, if interference is bad then sticking random capacitors on the in and out seems to clean it up enough.


RTL usb dongles can make a cheap spectrum analyzer to see what's really going on -

https://www.rtl-sdr.com/spektrum-new-rtl-sdr-spectrum-analyzer-software/

Thanks for that. I've got so much else to fix and deal with, I really don't want to have muck around fault finding with these little critters. Could really, really do with something that actually works out of the box.

 

[savageseadog]

Put ferrite cores on the wiring in and out. They need to go nearest to the converter with the capacitor to the outside if you fit one.

 

[GHA]

Haven't tried them, but the blue sea ones seem to get very good press -

https://www.bluesea.com/products/category/30/USB_Chargers

 

[dom]

I use these approx 0.75m from VHF with no interference probs at all:

https://www.ebay.co.uk/p/Power-Supp...itm=202284030463&_trksid=p2047675.c100623.m-1

How much current are we talking about?

 

[Daverw]

Unfortunately bad designs lead to the issue, it’s mostly RF interference and little that can be done. Ferrite rings not likely to work but worth a try, separation can help as they are low power. Lots of these uniits from China do not comply with regs to stop this just as many LED units have the same issue

 

[lw395]

I've used random cheap ones from ebay without signifcant problems.
If it's critical, and current is low, a linear regulator such as a 7805 or LM317 is your friend.

The pcb modules are not subject to EMI or EMC 'regs' as they are components not products.
Mounting a pcb module in a metal box with some filtering at input and output is one approach.

 

[JumbleDuck]

Haven't tried them, but the blue sea ones seem to get very good press -

https://www.bluesea.com/products/category/30/USB_Chargers

I have the Fast Charge one, and whil eit works pretty well, both my phone and my tablet think they have been charged to 100% in under an hour whereas in fact neither is anywhere close. Most odd.

I have a spare BlueSea 2.1A + 0.5A panel mount dual USB charger going spare, if anyone wants it. Cheap.

 

[LadyInBed]

I have a couple of Maplin 12 to multiple V o/p which work well. I haven't looked to see if they are still trading!

 

[PotatoNavigator]

Search for 'buck converter' there are loads, mostly reasonably priced, here's and example:

https://www.amazon.co.uk/MP1584EN-D...qid=1524226536&sr=8-4&keywords=buck+converter

As previously stated, a combination of ferrites and capacitors should reduce noise.

 

[Topcat47]

I had a few that didn't take to being fitted to the boat, not liking the salt laden atmosphere or occasional drips. My current on is mounted in a plastic food box wit a couple of vent holes in to sides and bottom. It's worked happily for more than 5 years. I can't remember the make as I'm nowhere near the boat. but it's a good mounting suggestion.

 

[BabaYaga]

Just wondering if anyone has any good recommendations for these? I've tried several, and they've all caused interference on both marine band VHF and stereo FM radio bands. They're extremely useful little gizmos but i would like to loose the interference.

If you are looking for a plain buck converter (no USB socket) I can recommend this one, which I have used a couple of years, without any interference problems:
https://www.ebay.com/itm/12V-24V-to...AMP-US-Ship-/221559430900?_trksid=p5731.m3795

 

[rbmatthews]

Put a switch on the power supply to the 12v socket. That way you can just turn it on when you want it, and only have RF interference then and not all the time. Ferrite cores also help, but won't eliminate it entirely, in my experience.