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Old 09-10-2017, 3:39 PM
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majoco majoco is offline
Join Date: Dec 2008
Location: New Zealand
Posts: 2,752

Generally I find that it's the low current rating warts that put the voltage up - I guess they use finer wire and a smaller core for the low current but then have to put more turns of wire on to compensate for the resistance of the wire - hence when run a the lower-than-rated current the voltage gets higher.

If you have the skills, it's not hard to make a regulated power supply but they're usually bigger than the wart. There is a snag with regulated supplies though - if you plug them in to the radio first and then into the wall, there is often a big spike in voltage before the regulator has time to regulate - if you see what I mean!

Another snag with the Zenith 3000-1 is the earphone type socket they have used - as you put the power plug into the socket it shorts out! Hopefully the wart will hack a dead short for the half-second it takes but it's not good. If I was going to use mine frequently I would change the socket for the conventional centre-pin type.
Cheers - Martin ZL2MC - Palmerston North

Last edited by majoco; 09-10-2017 at 3:47 PM..
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