High Current Maida

[kingneb]

I refuse to use switching regulators in tube amps. Did they have those in the 1950s, no way! Same goes for linear regulators but at least they are closer to the classic CLC power supplies. The good news is thet they reject more ripple, weigh less, are less bulky, and cost less!

I found a regulator, the LT3080, that looks to me like it allows for much more efficient operation. No 22k ohm resistors required that dissipate 3 watts each of power. Plus adding soft start is much simpler!

[jackinnj]

Originally Posted by kingneb

I refuse to use switching regulators in tube amps.

Didn't I say to copy a leaf from the SMPS syllabus? -- think of how you can control the loop via the primary side of the transformer. You can opto-couple the control circuitry. Controlling a volt on the primary side is like controlling 5 volts on the ouptut side.

Linear has a dozen or more designs of gate drivers, or complete packages which effect the same thing, and the late Jim Williams put out an ap-note 3 ro 4 years ago.

[TheGimp]

Actually, they had linear regulators in 1950. They were tube based but they were linear in operation and use the same principals of modern SS linear regulators.
Would they use SS in designs in the 50s if they were available?

I know so. Manufacturers were willing to adopt Selenium stack diodes when they became a reliable technology. Same for other SS devices. It was all a cost/benefit analysis in it's basic form. There are a lot of tube amps that used solid state rectifiers once they were readily available and competitively priced.

I'm not dissing your choice to use no sand in your designs. I'm just pointing out that the technology is older than most assume. Also, manufacturers were willing to adopt whatever technology helped their designs.

[tomchr]

They also had switchmode supplies "back in the day". They were called vibrators and operated at a rather low switching frequency compared to today's SMPS. Used for automotive applications among other things.

~Tom

[jackinnj]

Originally Posted by tomchr

They also had switchmode supplies "back in the day". They were called vibrators and operated at a rather low switching frequency compared to today's SMPS. Used for automotive applications among other things.

~Tom

One our Chryslers (old enough to remember) had a tube a.m. radio with vibrator supply.

Here's the application note on Linear's site:
http://cds.linear.com/docs/Applicati...te/an118fa.pdf

[Elvee]

Originally Posted by kingneb

What I am looking for is something to prevent ON/OFF spikes, capacitive loads, etc from ruining the regulator, which riccoruder's suggessions address. Should they be sufficient or should I add something else as well?

I also am looking for short circuit protection that protect the semiconductors until a slow blow fuse in the power transformer primart can react.

Have a look at this circuit, it might be of some interest for you:
Simple HV series regulators

[Alain Dupont]

Ben, {kingneb }

I did build the TJC High-Voltage (Complete) for about 250/350 volts some time ago....

I did make about 3 modules for my SE 6C33C and had great results. The lowest ripple ever!

John is always bringing new idea's, and wow it's nice to see such a great site!!

Alain.