First I would like to thank you all for the quality of the discussions and specially to Audioguru and RedWire for the excellent job regarding the new PS design.
I have built the new version and I'm very pleased with it (btw, I built the old version too, but I use it nowadays as spare one for low power circuits only).
Some thing that I'm concerned about is power dissipation. I use one heat sink of 12 x 5 x 3 cm (about 5 x 2 x 2 1/2 inches) for each Tr plus a salvaged fan from a PC PSU. So far all is well (despite the death of a power transistor and consequently the death of a power led during testing) but I'm worried about delivering 3 amps at say, 5 volt.
So here is my question.
I've read in this forum (I think it was Hero999) about tap changing as a way to reduce heat.
In fact, the transformer that I got has two secondaries: one at 30V and the other at 9V (it used to power a huge dot matrix printer).
I tried to google a tap changer circuit but to no avail.
Does anyone know how to do it? I thought about using a SCR but sadly, at least for now, I lack the knowledge to face such a task.
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0-30V Stabilized Power Supply
in Projects Q/A
Posted
Hi
My name is Fernando and I'm from Argentina.
First I would like to thank you all for the quality of the discussions and specially to Audioguru and RedWire for the excellent job regarding the new PS design.
I have built the new version and I'm very pleased with it (btw, I built the old version too, but I use it nowadays as spare one for low power circuits only).
Some thing that I'm concerned about is power dissipation. I use one heat sink of 12 x 5 x 3 cm (about 5 x 2 x 2 1/2 inches) for each Tr plus a salvaged fan from a PC PSU. So far all is well (despite the death of a power transistor and consequently the death of a power led during testing) but I'm worried about delivering 3 amps at say, 5 volt.
So here is my question.
I've read in this forum (I think it was Hero999) about tap changing as a way to reduce heat.
In fact, the transformer that I got has two secondaries: one at 30V and the other at 9V (it used to power a huge dot matrix printer).
I tried to google a tap changer circuit but to no avail.
Does anyone know how to do it? I thought about using a SCR but sadly, at least for now, I lack the knowledge to face such a task.
Thank you all
Fernando