LM317 question.

[hevans1944]

Well, the ATX power supply does provide a well-characterized base from which to start. You can easily add "bells and whistles" externally to suit your purposes. I plan to do just that after I resurrect my home electronics lab after several decades of neglect! I might even purchase a new ATX so I will have a spare for use with my personal computer towers. Adding to the ATX outputs may require building or purchasing buck/boost switching regulators for variable output, but being an amateur radio operator I am somewhat leery of putting a switching regulator near my radio equipment. Of course, I could just turn it off while I am doing amateur radio things if it turns out to be a problem.

So, here's to a happy new year for all of us, and more powerful power supplies! I am anxious to get my 100 watt linear RF amplifier on the air, and I already have a nice 12 V @ 30 A linear-regulated power supply for it. Just a matter of getting a decent antenna up that will handle the power. I am going to design the antenna to handle two kilowatts, but expect the 100 watt linear will do just fine for now. High-power linear power amplifiers for the HF radio amateur bands are readily available, but if I decide I need to run the full legal limit, I think I would like to roll my own using obsolete high-vacuum tube technology. Something about the smell and the warm glow from the tube filaments appeals to me.

 

[sureshot]

Most of what I'm powering is radio equipment. The reason for playing about with the higher current, although I have run into noise from the supply's when using smps typically atx and server units I've converted. So I'm trying to go with linear and series pass transistor circuits. I have built a single TIP2955 transistor and 78S12CV voltage regulator, but trying to see if my resistor values are correct in the circuit help gatagery. I posted a 30 Amp version in there. Although I only want a two transistor version up to 10Amps at +12 Volts. In the schematic I posted I'm struggling with R7 and its position, surley it goes to the base of the trasistors , and not in series with the input. That bit has me puzzled. I'll try and post the picture here, but having problems uploading images. And my version only needs two transistors, I made the base resistor needs to be 16.6 ohms and two ceramic 10 watt 0.5 ohms resistors.

 

[sureshot]

No it won't let me upload the schematic, but its in my post in circuit help section of the forum.

 

[hevans1944]

You received good replies on the other thread. Just remove all the extra transistors. Leave the remaining base resistors alone. The resistor in series with the voltage regulator is in the right place.