MegaWatt vs. Chinese Imitation 30 amp switching power supply comparison

[Megawatt]

Thanks John, also good to know about the s-700.

Click my link in my signature and check it out.

 

[gamegetter]

i somehow missed the 700, or i would have bought that myself!

One question i have on the 400, as i have not used it yet:

Is the voltage set at 12v coming out of production? I plan to put a meter on it, but just thought i'd ask,
thanks for all your help and support.

 

[Megawatt]

I sent them at 12.2 before shipping.

 

[222DBFL]

Thanks megawatt!! Great supplies. My local bud just got the 50amp one and loves it!! I have had great luck with my s400. Keep up the good work!!

 

[pacset2]

In an earlier thread about the various switching power supplies available on Amazon, there were questions posted about the difference between the authentic American made MegaWatt 30 amp supply and the cheaper Chinese imitation supply. I've purchased both supplies and used them extensively with my Elecraft K3 and can now report on the major difference.

First, here are links to the two supplies in question:

MegaWatt 30 amp switching power supply:
Amazon product ASIN B00JZBE97U
Chinese 30 amp switching power supply:
Amazon product ASIN B00D7CWSCG
The two supplies look identical, although the Chinese supply does not include an AC power cord. However, the performance difference is significant: The MegaWatt has no "hash", while the Chinese unit has terrible "hash". I took pictures of the interference on the Panadapter that shows the difference visually.

First, here's the Chinese supply:

The slanted lines in the pic are heard in the receiver has a high pitched whine that slowly lowers in pitch and interferes dramatically with your RX signal. It can get so bad that it can wipe out the intended signal.

Here's the same frequency only moments later on the Megawatt Supply:

Notice that there is no slanted lines; only clean signals of the transmitting stations. That's because there is no hash. They say a picture is worth a thousand words, but in this case a video demonstrating the difference between the two supplies tells the whole story:

 

[pacset2]

After watching this video on the MegaWatt power supplies , I'am sold on it. Made in America, nice. I will order the S-400-12
Thanks Worldwide DX and MegaWatt
W6KLE

 

[222DBFL]

Gamegetter, Google megawatt power supplies and it will bring up the web page. The stats for the S700 are there. I was like you and didn't know they had these. Would have done the same. Gotten the S700. But for what I use mine for, it's plenty and is a workhorse. Stays on for days at a time. Not always with a load on it, other than the fan. Gotta go over and check out the s700 In person at my buds. He loves it! Says I can power everything I have lol!!

 

[gamegetter]

thanks 222, i may get one in the future anyway!

 

[Megawatt]

Sorry about that, we only just got the S-700-12 on the market after extensive testing and tweaks. It's working out really well so far.

 

[357]

so the clone....if you put a 2-3 amp load on it, will it still birdie?
Does it only birdie on 710AM?

The megawatt is made in the USA with USA made components?

Thanks

 

[Megawatt]

so the clone....if you put a 2-3 amp load on it, will it still birdie?
Does it only birdie on 710AM?

The megawatt is made in the USA with USA made components?

Thanks

I cant speak for Tim's test because I don't have his Chinese power supply to test. The ones I tested through RF and harmonics all over the place The Megawatt like any and all electronic components has parts in it that come from countries all over the world. The Megawatt is designed and assembled in California.

 

[Moleculo]

so the clone....if you put a 2-3 amp load on it, will it still birdie?
Does it only birdie on 710AM?

Thanks

The cheap supply has RF hash all over the place on the HF band. It seems to get worse, the lower you go on the band.

 

[BBB]

I just watched the video of the (4) S-700-12 power supplies paralleled. Very interesting that there is no need for data wire for current sharing between the multiple units. How is that achieved? And just to clarify, you can hook as many of these in parallel as needed or is there a limit?



Currently, I run a DuraComm 100 amp supply that has (4) Meanwells paralleled but they have a data/ current sharing wire so the multiple power supplies stay "happy" in the parallel configuration.

I have seen (1) Meanwell RSP-3000-12 that will do close to 14 volts at 200 amps retail for around $550. Not sure if the (4) S-700-12's to get 200 amps are the deal at $180 a piece (or $720 total) just sayin'

http://www.alliedelec.com/mean-well-usa-rsp-3000-12/70069613/

Thanks.

 

[Megawatt]

I just watched the video of the (4) S-700-12 power supplied paralleled. Very interesting that there is no need for data wire for current sharing between the multiple units. How is that achieved? And just to clarify, you can hook as many of these in parallel as needed or is there a limit?



Currently, I run a DuraComm 100 amp supply that has (4) Meanwells paralleled but they have a data/ current sharing wire so the multiple power supplies stay "happy" in the parallel configuration. Thanks.

The TL494, in each power supply, monitors the voltage in the entire circuit. The currant is evenly divided by the identical load due to parallel connection. Yes, as many as you want can be connected together in parallel.

 

[Megawatt]

Not sure if the (4) S-700-12's to get 200 amps are the deal at $180 a piece (or $720 total) just sayin'

First off the S-700-12 a way better power supply and secondly they are only $110 each not $180. Thats $440 total for 4. The Meanwell is dirty and has to run on 220V. www.12voltpowersupplies.us