I am looking to get a decent, not expensive, bench supply for hobby and other work. I am leaning towards a 3-channel supply, linear.
Capacity at least 3A/channel. Budget is $300 or less. I've been looking used but, nothing yet.
Basic hand adjustable is fine. I don't need programmable.
The MATRIX MPS-3003H-3 is on my short list. It seems like a bargain but, I don't want to regret going too cheap.

I'd love to hear what others like to use.

Th

 

What you need will depend entirely on what you are going to use it for. I built my own, 2 x 0 to 20V 1A, 5V 1A.

 

+1 Exactly.
I built my own 1A @ 5V for digital breadboard circuits. This is the one I use the most.

 

I have built many regulators and supplies over the year. Most were lost during moves. Been there, done that.
Now that I am older I am getting lazy and want a nice bench supply with knob controls. I'd rather put my build time/energy into
other projects. That plus I need some supplies in order to wrap up another project over the next 2 months.
I have one 0-32V/5A bench supply. It is switcher supply, basic cheap. Works ok but, I need two more rails, feeding analog circuits so I want
linear to reduce noise.

Wants:
+-30V/3A for two channels, 3rd channel can be fixed 5V or less.
linear supply (reduce switcher noise) .. at least linear output stages.
settable constant current/constant voltage mode
floating outputs so I can use them a either all + supplies or, tie two together as +-


Thx

 

Capacity at least 3A/channel. Budget is $300 or less.

Anywhere near $300 is a lot to spend. I'd spend it on something more useful (scope, signal generator, bench meter). What do you plan to do?

I have a few Tektronix PS 503A triple supplies (+/- 0-20V/1A and 5V/1A) and I can't remember the last time I used one. About the only time I need more than an amp is when I'm testing power devices or voltage regulators.

I have half a dozen bench supplies and several dozen wall warts and use whatever power supply is convenient. Sometimes it's a USB charger, laptop supply, Velleman 30V/3A, Wanptek 30V/6A; all switching supplies. The Wanpteks cost me around $45 each, the Velleman was around $70 and around 3X the size of the Wanpteks.

I have several linear bench supplies and I don't use them anymore.

 

I have a decent Rigol scope and Fluke DVM already. One triple supply would be nice. It would reduce power cord clutter on my bench.

 

It would reduce power cord clutter on my bench.

That's your prerogative.

I use these C14 to C13 splitters:

I built a "shelf" to put on my bench:

Whatever you buy, pay attention to the power jack spacing and order. The spacing and order on the Velleman is dumb. I made an adapter so I could use dual banana plug leads.

I bought Wanpteks that didn't have earth ground because they put it between + and -, which is dumb. Back in the day, they always put earth ground on the outside and provided a shorting bar when you wanted to connect - to earth. At least Wanptek uses the correct jack spacing and 5-way binding posts instead of those safety banana jacks.

 

I got a used combined single power supply, signal generator,

I have a decent Rigol scope and Fluke DVM already. One triple supply would be nice. It would reduce power cord clutter on my bench.

I bought used on Ebay, a combined 0-30V PS, function generator, RF signal generator and frequency counter. It is typically the only power supply I use when experimenting. I have another adjustable one though which I use occasionally. I still have a 5V supply that I built when the 7805 was new, and a ±12V that I built using Zener diodes and pass transistors. I use these 50 year old pieces of junk once in blue moon.

 

another thing I like about a bench supply is the current readout. It's good to see the current draw. It can often indicate a problem in your test circuit.

BTW, what is the proper jack spacing to use those dual banana plug jigs? Good idea.

 

another thing I like about a bench supply is the current readout. It's good to see the current draw.

I used homemade power supplies and wall wards for decades, so I didn't become dependent on voltage or current displays. The last 4 I bought (all switching) have the displays. I could have paid more for Wanpteks with 4 digit displays, but it wasn't worth the price difference. I still use a meter when I care about supply voltage.

what is the proper jack spacing to use those dual banana plug jigs?

0.75". The Velleman used something like 0.8".

 

You might consider one of the small buck-boost modules.

I used one of these modules plus an Xbox power supply to make a panel that I screwed to the shelf above my bench. It's handy, the small display can be seen easily and it takes up no room. From this panel, I get 5 volts at an amp, 12 volts at 12+ amps (depending on the exact Xbox supply) and variable 0 – 30-some volts at 5 amps. The module shows the voltage and current, power, energy used and even has a graph of V vs A.

The Xbox brick is unique in that it alway supplies 5 volts, but 12 volt supply is controlled by switching a line to +5. So the 5 volt output is always live, but the 12 volt output and variable output are enabled by a low-current switch.

Xbox supplies are pretty common in thrift stores. Some variants supply 16 amps. I connected it with about a 3' cable so it can live out of the way.

Very handy for roughly $25 of materials.

I'll supply more details if this is interesting.

 

I may splurge for thetriple supply. The Matrix MPS-3003H-3 is a good deal at ~ $180. I checked reviews and they seem pretty good. Noise spec looks good as well. I have been using an Eventek KPS305DF ... 32V/5.2A switching supply. I have had no problems but the switcher noise on the output could be lower. I see about 50mVpp at 5.0V output.

In any case, I have contract work involving some analog circuits so I am going linear. Also, I can write this off as a business expense, which helps with the cost. In the past, before I retired, I used HP/Agilent/Tektronix equipment in the lab all the time. Great stuff and I got spoiled. Now, I have a poor man's lab in the basement and my budget is tight.

I'll make a decision by tomorrow.

 

Right at the top of your budget is SPD3303C.
Low noise, 3 channels, all isolated.

 

Yeah, I looked at that. Looks nice but, at the top of my budget. Depends on what mood I am in tomorrow.

 

I have been using an Eventek KPS305DF ... 32V/5.2A switching supply. I have had no problems but the switcher noise on the output could be lower. I see about 50mVpp at 5.0V output.

If you haven't been having problems with supply ripple, I think you're worrying about nothing.

I used a Heathkit ET-3100 Experimenter for years before I found out that the power supply had around 150mV of ripple. I had used it for digital and analog breadboards and only had one circuit that was affected by the ripple. I thought it was just a crappy design, but my other ET-3100 didn't have that problem, so I fixed the one that wasn't working.

Haven't had problems with ripple from any of the switching power supplies I've used (and I've used some pretty bad ones from AliExpress seller1 and seller2). Sometimes I don't put any decoupling caps on breadboards and the circuits still work. I don't recommend omitting them, but if I'm breadboarding a circuit to do a quick check of something, the caps never get added unless the circuit misbehaves.

 

Some analog ckts I am looking at can be affected by the ripple. The PSRR isn't that high in some circuits.

I am going to hold off until Amazon Prime day (16th) in a few ays, to see if any good deals pop up.

 

Yeah, I looked at that. Looks nice but, at the top of my budget. Depends on what mood I am in tomorrow.

With multiple channels you can also put them in Series or Parallel modes which in the case for this unit can provide 60V 3A or 30V 6A.....useful if you need it.

 

Have you looked at the offerings available from places like DigiKey and Mouser?

 

I like the ability to parallel or put in series.
I will check DigiKey and Mouser too, thx.

 

I like the ability to parallel or put in series.
I will check DigiKey and Mouser too, thx.

One thing to keep in mind about DigiKey and Mouser is that you can probably find the same supply that you find there somewhere else quite a bit cheaper (though their markup on equipment usually isn't as much as their markup on parts). So treat them as a way to get an idea of what is available that might fit your needs and an upper bound on the price, then go looking for specific supplies elsewhere. If you don't find it at a significantly lower price, then consider purchasing it from one of them as they generally have great customer service. Of course, you can also try to find one used on Amazon or EBay, but keep in mind that it becomes buyer-beware.