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Reviews Categories | Power Supplies | MFJ-4128 28 Amp Switching Power Supply Help

Reviews Summary for MFJ-4128 28 Amp Switching Power Supply
MFJ-4128  28 Amp Switching Power Supply Reviews: 4 Average rating: 4.3/5 MSRP: $84.95
Description: A Great one!
Product is in production.
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You can write your own review of the MFJ-4128 28 Amp Switching Power Supply.

K4HYJ Rating: 5/5 Feb 28, 2016 18:55 Send this review to a friend
It works as it should  Time owned: 0 to 3 months
Running an FT-857D. This supply holds voltage at 100 watts key down.
- Quiet fan
- connections front and rear
- cig outlet
- little!!
- no RFI

- short power cord
- no power poles

Function/performance-wise it works as advertised. Not much more you can ask!
AK1CT Rating: 5/5 Dec 27, 2015 19:35 Send this review to a friend
It works  Time owned: more than 12 months
This has powered my Kenwood 590 S and Icom 5100. I notice only a .1 Volt voltage drop when the 590S runs at full power, no affect on anything. The fan is not silent, but the Icom 5100 cooling fan is 10x louder than this power supply. Set it and forget it. It works.
KK4APV Rating: 2/5 Jun 9, 2013 08:21 Send this review to a friend
Finally, I am shed of this thing...  Time owned: more than 12 months
It gets two stars for doing what it's intended to do: Providing power to my two radios (HTX-242 and Yaesu 450D), and I'm not sure it really merits two stars.

Someone recommended MFJ power supplies to me about 18 months ago when I was just getting started into ham radio. (BTW, now I have my EXTRA!)

I'd read several reviews that said, "loud fan," but I though, meh, how loud can it be? Besides, I have some high-frequency hearing loss.

The first time I turned it on, I knew I'd made a mistake buying this thing. It was very, very loud. On par, I'd say it's louder than the exhaust fan in my 1962 NuTone range hood. And I'm not kidding.

As my visiting friends said, "Sounds like a jet plane taking off."

That may be a teensy bit over the top, but the point is, it's way too loud for in-home use.

After putting up with this thing for about 18 months, I finally bit the bullet and purchased an SEC 1223 (Samlex) and when I first turned it on, i said, "It's not working. I don't hear anything."

My ham radio buddy laughed out loud.

"You're just used to the wind turbine sound in that MFJ-4128," he said.

Turns out, he was right.

The new power supply is *silent* and had I known that such things could be had for under $100, I would have ditched the MFJ-4128 many months ago.

If you're deaf, it's probably a great power supply. But if you can still hear loud, obnoxious noises, I'd say stay away from this item.
AA2DK Rating: 5/5 Jan 10, 2013 12:37 Send this review to a friend
I Love It!  Time owned: 0 to 3 months
Wow, awesome little supply. Well-regulated, no RF hash, super quiet, built really well. Martin Jue, your stuff gets better every year!

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