/diy/ - Do It Yourself

>>1222871
When it comes to bench supplies, $40 IS ultra-cheap. You can get a dual output bench supply for $50 and up, but always check the reviews before you chink it.
Linear power supplies are necessarily heavy because of the transformers and the heat sinks. The only way to get around shipping charges for them is picking them up.
Surplus stores are a good option. Does your local university have a surplus store? You might be surprised what they just want to have rid of and how little they want for it.
Moar below

>>1222895
>13.8V
Sounds more like a ham radio supply, actually.
>20A
That's a lot to ask. Are you sure that 3A or 5A wouldn't suffice? Will you need higher voltages as well?

>>1222881
>>1222895
Personally, I just use a 12V 10A switcher or so, bring it out to a barrier strip at my workstation, run my bench lights off of it, and use those little dollar-each step-up/down boards to get whatever voltages I happen to need at that moment.
Building your own bench power supply isn't that hard, really. Consider one of these https://www.aliexpress.com/item/180W-36V-5A-Single-Output-Switching-power-supply-for-LED-Strip-light-AC-to-DC/32267285465.html followed by Pic related if you really need all the comforts of a lab supply.