On Wednesday, August 9, 2017 at 7:50:14 AM UTC-4, Big Bad Bob wrote:
On 08/07/17 05:09, Peter Wieck wrote:
On Monday, August 7, 2017 at 12:18:50 AM UTC-4, Big Bad Bob wrote:
I would expect hammond to be a bit better about things like this. It's
also starting to make my idea of a solid state switching HV power supply
for tube amps make a bit more sense... [eliminate imbalance, noise, etc.]
It still all comes down to an adequate source of power. A transformer of sufficient capacity is expensive, but it does also isolate the secondary, a good thing. And when dealing with B+ voltage that can be quite large, isolation is key to safe operation. And this applies to anything, including both instrument and audio equipment.
Peter Wieck
Melroes Park, PA
your standard switching power supply has an unisolated side that drives
a toroidal isolation transformer with a relatively high frequency. So
the isolation is there, but also quite a bit of potential switching
noise. I figured I'd use an off-the-shelf switcher to produce ~20V
[like a laptop computer, for example], then use the reasonably clean
20VDC to produce all of the other voltages.
I suspect that the total cost per unit would be a LOT lower for a DC
C
converter + inexpensive laptop power supply.
Hopefully the inexpensive laptop supply would last more than 5 years
though... [I have better confidence in my own designs, for the rest of it]
--
your story is so touching, but it sounds just like a lie
"Straighten up and fly right"
I just had a look at the PS for my ACER 3610 Laptop, 19V, 3.5A. That will not power much of a toob amp, no matter how cunning your designing abilities are. Toob amps are hungry.
Did you check any of the HV CT wdgs in your transformer stash yet with regard to different resistances in the two halves? Or afraid of what you will see!