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Product Comparison: Amazon 30 amp switching supply vs. MFJ-4275MV

Alright, I hooked up my power supply using Captain Kilowatt's instruction and the power supply doesn't work!? All connections are tight, I used spade terminals. The green wire is on the ground but is there any possibility that the black and white wires are reversed? That is, the white wire should be on the L and the black wire should be on the N? Should I go out and get a 2 wire cord somewhere? I was really looking forward to being back on the air today. Help!! (Please)
 
GND = green (ground)
N = white (neutral)
L = black (load or line)

Make sure you you have the 115/230 switch on the side set to 115 (assuming you are in a location where 110-115v is the norm). Make sure the cord is good. Going to a 2 wire will not make a difference if your current cord is known to be functional.
 
Thank you again tba02

I went to Home Depot and purchased a new power cord, attached new spade connectors and still no power. It is on 110-115v. I must have gotten a dud. I'm rather annoyed that by trying to save money on a power supply I feel like I should have just bought a Pyramid and wouldn't have had this aggravation and would be talking on the radio right now. Rant over
 
psu3-jpg.14484


From the looks of it I would say the first three terminals from the left are all the same, positive voltage out. The next three are negative voltage out. The next terminal labeled with the schematic symbol for ground is for the GREEN wire from the AC power cord. The terminal labeled N is for Neutral and gets the WHITE wire from the AC power cord and the last terminal labeled L is for Line and gets the hot wire in the AC power cord which is the BLACK wire. Nice to see the 120/240 switch. A lot of units need to be wired differently and have no such switch.

Alright, I hooked up my power supply using Captain Kilowatt's instruction and the power supply doesn't work!? All connections are tight, I used spade terminals. The green wire is on the ground but is there any possibility that the black and white wires are reversed? That is, the white wire should be on the L and the black wire should be on the N? Should I go out and get a 2 wire cord somewhere? I was really looking forward to being back on the air today. Help!! (Please)

In an AC circuit the WHITE wire is the Neutral wire and the BLACK is the hot wire connected to the LOAD. You can test this by holding onto a bare spot in a BLACK wire and turning the switch/breaker on. :p The WHITE wire is connected to the ground back in the main electrical panel entrance. You had it connected up properly but there is something else wrong somewhere.
 
Thanks Captain, I'm going to order a "regular" power supply later today after I finish my yard work.

In my frustration to find out what was wrong I neglected to realize that I hi-jacked the thread...and for that I'm sorry.
 
Update...So I disconnected the radio leads and just had the Green, White, Black power wires hooked up and suddenly the little green LED indicator lamp came to life. As soon as I attached the + and - to the radio the light goes out and I have nothing. Why is it cutting out with a load????
 
Check the supply voltage and make sure you have the pos and neg on the same ports like port 1 pos and port 1 neg.
 
My concern would be that the Amazon PSU would only put out the 12Volts as advertised and not the 13.8 volts most power supplies put out. Does it have a means of varying the voltage?
 

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