Review of the MFJ-423MVP 30 amps Power Supply

This video is about the MFJ-423MVP, 13.8V / 30A Power Supply (PSU). People were asking me about the fan noise in the unboxing video of this unit, so I did a test using my TS-2000 in FM at 100W. Check it out for the conclusion and please subscribe!

73
Pascal VA2PV

 

Made a mistake in the title, it's the MFJ-4230MVP. 73

 

I have 3 of these power supplies. I have experienced ZERO issues with them. One is my shack power supply, running an IC-7300, ID-880h, LP-100a and MFJ-998. One is a dedicated power supply for our local public d-star hotspot and digipeater. The other one is my go/portable power supply. I have no complaints regarding these units. I would recommend them to anyone.

 

Just a suggestion... open up the supply and look at the assembly and solder quality inside. On a failed unit my buddy repaired, cold solder joints, solder bridges and solder balls caused the supply to fail shortly after the warranty period expired. Upon looking inside, the supply looked hand assembled "...by a 3-year old". But don't take my word for it...

Apparently, HB9RYZ had some equipment destroyed by one:
http://www.eham.net/reviews/detail/11431

And N6YFM had some comments on his failed supply:
http://www.eham.net/reviews/detail/11431?page=2

Thanks for the review, but wish you had opened up the device to do a close-up of the solder assembly. Maybe MFJ has improved after all the feedback.

 

Same issue here. Mine quit 3 weeks after warranty. I inspected the PCB, and it looked like it was assembled and soldered by an angry 3-year old. Located 2 loose solder balls and one solder bridge partially shorting. Spent 2 hours resoldering everything, cleaning it up, and got it working again.
You can read my full review here;
http://www.eham.net/reviews/detail/11431?page=2

As is so common with China goods, this unit is made by a China OEM, and sold in multiple quality grades based on what the USA vendor wants to pay for. They use different assembly lines with different human labor, some trained and paid that way, some not trained and paid that way.

Both MFJ and PowerWerx purchase this same unit from the manufacturer.
The main chassis has a connector for the front panel. MFJ chose an analog front panel,
PowerWerx chose an LED digital front panel. See;
https://powerwerx.com/variable-power-supply-digital-meters-30amp

I have both units, and had them apart on my bench. The units are IDENTICAL.
Same main chassis, all parts the same, except different front panel options.

PowerWerx paid for a quality assembly line at the OEM in China. The soldering is
top notch, the insides are very clean and commercial looking, and we had to cut a
warranty label to get inside the chassis.

MFJ paid for the lowest cost option, and then clearly fought with the OEM to go even lower.
There was no warranty label, and the insides were beyond crap. It was like they found some
homeless people, shoved soldering irons in their hands, and commanded them to "go play".

My experience with traveling to China and dealing with many companies, is that they have
on average a menu of anywhere from 3 to 5 tiers of quality grades, depending upon what you wish to pay for. They can make some VERY good equipment. Witness Siglent signal generators and Rigol oscilloscopes. Witness the PowerWerx version of that same power supply.
They can also make some of the most pathetic crap seen anywhere on the planet, like
their $25 fake Rolex watches where the adjustment knob and entire shaft pull out after
only 3 weeks, or the others that I played with where the hands and even the dial faces fell off
inside the glass

So about MFJ? Um, er, ah, RUN. Run very very fast!
You can buy most of the same type of products from someone who cares.

Neal

 

I don't have the patience for video reviews. I appreciate the written comments above. No MFJ supply for me. I can take the risk of something like that with some things but not with a power supply that could be running a piece of equipment worth vastly more than the supply. Of course one could buy the MFJ supply and open it up on delivery and start re-soldering and cleaning it up, but my time is worth something too not to mention the hassle factor and having a strong bias against having to fix something brand new that shouldn't be broken.

 

Neal... how do you REALLY feel?

 

Very nice video . Yes I have a similar power supply (looks just like it) by another company and it works very well, I'm happy with it. I would like to see inside that MFJ power supply myself though

 

Pretty darn insightful on manufacturing from China. THANK YOU...73 and have a great weekend! NU4R

 

I have this exact power supply. It has been running 24/7 for about a year and has never failed me.

 

When you get one running for over 6 years non stop then make a point. Buy a good Astron.

 

Jeff:

Glad yours is still working, but suggest you open up your MFJ power supply and shake out the solder balls, check for bridges and cold solder joints. N6YFM was lucky, he could have had the same experience HB9RYZ had: "I switched the power supply to ON and suddenly the JUMA PA100-D Amplifier was destroyed!!!! " No internal protection can protect against loose and stray metal inside a power supply.

 

Thanks Pascal,

Always enjoy your video's. Very useful information.

 

Michael:

Astrons are not perfect, either. But they are certainly a stable product, usually well built, and easy to repair. Having worked with them for years, the two major causes of failure I've seen are:

1. Power/Ground bolts rotate in their mounting holes when tightening power cable lug securing nuts - there is NO positive keying of the bolts in their holes and when they rotate, even a few degrees, the wires attached to them inside the chassis can and often will cross and short, causing a variety a damage. Even when opening up a brand new Astron, check the clearance between internal wiring points at the power/ground bolts and make sure they are as tight as possible in their mounts. DO NOT torque down the nuts on the supply bolts when attaching power leads or this problem WILL happen. Finger tight, plus a quarter turn is a good approach (depends on how much wiring is attached).

2. The main electrolytic capacitor in the Astrons is normally rated only a few volts above actual working voltage and is prone to failure. I generally replace it with a much higher rated part, when it fails. And the caps can fail in any of several modes: Open, short or, (most frustrating) partial short where the supply appears to work normally until a significant load is placed on it, whereupon voltage drops and develops severe ripple. A load bank is very handy for testing any power supply, and can be easily built from large resistors.

There are several good sites describing how to repair Astron linear supplies:

http://www.repeater-builder.com/astron/astron-repair/astron-repair.html

http://www.repeater-builder.com/astron/astron-intro-stuff.html

Astron is very responsive to requests for key parts, like the regulator board and crowbar SCR:

http://www.astroncorp.com/

That said, most of my main supplies are Astrons, and none have ever damaged my equipment.

Brian - K6BRN

 

I've ran mine for over a year with zero problems. I use it at home and take it to FD and use it in my go-kit. No issues and no noise!