John Miller writes:

wrote:
I am relatively new to ham radio. I am wanting to build a base station
in my bonus room and use some mobile radios up there.

snip

I like the idea of building one but not sure if it would cost more that
way or not. What would I need to build one besides a transformer and
rectifier?

Welcome to the ranks; an excellent reference is the ARRL handbook.
Your local library should have a copy or copies.

Quick answer to your question: in addition to transformer and
rectifier, you'll need a safe enclosure, overload protection, voltage
regulation and filtering.

These days, though, it will probably cost you more to build one,
unless you have a well-stocked junk box. Didn't used to be that way.

Alternatives: PC power supply (you may need a load on the +5 VDC line for
the +12 VDC to be properly regulated) and eBay (always many good power
supplies available).

Building one is certainly an option and a good education experience
which may outweigh the additional cost and effort.

But, maybe not best as a first project, mainly due to the need
for high current regulation but still not out of the question.

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John Miller
email address: domain, n4vu.com; username, jsm
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