MP1584 Buck converter 3A


ON5KQ
 

Rob,
I made a short test:
- 13.0V DC supply from a switch mode power supply by Meanwell : Type S-100F-12
https://www.meanwell-web.com/nl-nl/ac-dc-enclosed-power-supply-output-12vdc-at-8-5a-s-s--100f--12
I know this unit is a bit noisy and noise can be seen in the receiver, if used with antenna relais, etc...
However I have it in the shack, doing nothing... and it can deliver a lot of Amps...

The output of this SMPS to the input of the buck DC-DC converter - nothing to adjust for 5.0V output - then a 1inch long smal cable into the kiwi

Result:
- No ant connected:   absolutely no noise at all visible from DC to 30Mhz... really absolutely NOTHING. The result was absolut the same than my linear power supplies and much better as shown by Clint during the video-conference.
- connected my relatively large vertical active dipole (2x3.5m with LZ1AQ pre-amp) - after 15db attenuator in front of the kiwi...: I cannot find any carrier or noise from the power supplies. It is interesting, that also the Meanwell SMPS does not harm at all...

So - this is really a good solution I think and I will use it at the new location...

Ulli, ON5KQ

PS: The linux PC is my mobile laptop... I must re-install it anyway and will come back to you, if the WD-installation problem persist. I then can also provide remote access, if this would help...


Rob Robinett
 

I have accidentally applied 12V to the Kiwi without experiencing any damage.  I know there is circuitry in the BB to protect ti from over voltage, and it appears the Kiwi board itself has protection as well.

On Fri, Oct 9, 2020 at 5:33 AM ON5KQ <ON5KQ@...> wrote:
I purchased the buck converters to step down from 12V DC to 5V DC to power the kiwi-rx
Many vendors are selling them on Amazon and e-bay

As they arrived I am astonished, that the Buck converter modules do not have the potentiometers installed as shown on the pictures on the Internet.
I was afraid, they would not be useful, in case the output voltage is not  5V.  I was lucky however - a quick test with 100mA load showed 4.99V DC output with 12.3V DC input - so even without potentiometers they may be used.

Question:
I am afraid, that if something wents wrong with the small modules, the full 12V DC may reach the Kiwi power input plug. What should I do best to protect the kiwi for overvoltage when using the small ? Any good effective idea which would prevent big damage to the kiwi ?

Thanks for some advice,

Ulli, ON5KQ



--
Rob Robinett
AI6VN
mobile: +1 650 218 8896


ON5KQ
 

I purchased the buck converters to step down from 12V DC to 5V DC to power the kiwi-rx
Many vendors are selling them on Amazon and e-bay

As they arrived I am astonished, that the Buck converter modules do not have the potentiometers installed as shown on the pictures on the Internet.
I was afraid, they would not be useful, in case the output voltage is not  5V.  I was lucky however - a quick test with 100mA load showed 4.99V DC output with 12.3V DC input - so even without potentiometers they may be used.

Question:
I am afraid, that if something wents wrong with the small modules, the full 12V DC may reach the Kiwi power input plug. What should I do best to protect the kiwi for overvoltage when using the small ? Any good effective idea which would prevent big damage to the kiwi ?

Thanks for some advice,

Ulli, ON5KQ