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The best regulator I've built so far

Hi Teddy
Could you show a schemo of this circuit to include a 337 for a - rail ?? and also indicate values for +12 / -12 dual supply I would like to build this to compare to my SLA's in a noise test on our AP, would that be possible please.
Paul
 
Hi Pers, how are you and the team at Lundahl ???
Yes we do have very competant engineers who could offer their advice, however, I have noticed that this very same question has been asked before on this thread and it is Teddy's project and not mine, I would like to build a respected and recommended linear supply from here to conduct some tests to compare to my SLA / Cap supply, in fact it has been advised by other members to look at the TeddyReg.
 
Teddy that is very kind, thankyou very much, do you anticipate PCB's becoming available for this project, or is it a breadboard affair??
thanks again
Paul
 
I just finished building my new regulator board for my self-built pre-amp digital xover. 4 TeddyRegs based on the fetlington design - 3x 5V and 1x 3.3V (all are adjustible though), plus 1x LM7805 5V line, 1x 3.3V LM350 line and a +/- 15V line from a LM7815 and LM7915.

It took a long time to build, but it is a lot neater than my current regulator board (the design I have attached also). I'd be interested to hear your thoughts on that design and hopefuly you will say they TeddyReg is better! :D

So, thank you Teddy!

teddyregspt6.jpg


My old Regs.
oldregdesignwe5.jpg
 
Tenson said:
I'd be interested to hear your thoughts on that design and hopefuly you will say they TeddyReg is better! :D
Click to expand...


I've built something similar once, and there is a big difference. The point is that large capacitors don't filter well at high frequencies, while the ceramic is doing a great job in that area.
 
Teddy,

Do you see the Teddyreg as a circuit for cleaning up rectifier hash, RF and the fading top end of a previous regulator, or a full bandwidth device. That was my earlier impression but I see than the turnover frequencies of R4/C4 and R5/C5 are .015Hz and 9Hz respectively, i.e. a lot lower than I expected.

Do you have some 10uF Wimas on the way?

David
 
I'm using it as full bandwidth device. With these regulators you can use a low power transformer and simple smoothing capacitors to create a really high quality power supply.

No I didn't order the 10uF Wimas, for this application I really like the Tantalum/Ceramic combination. For the audio signal I usually use large Polypropylene when size allows, or BC128. But I should try these Wimas one day too.
 
Teddy,
you stated that the reg is not fit to feed a clock and as I understand your reason was the long settling times.
But I still want to give this reg a try for the clock of my soundcard.
Do you thing the clock will work OK if the desired voltage is reached before I boot the computer?

Greets,
Klaus
 
Radian said:
Teddy,
you stated that the reg is not fit to feed a clock and as I understand your reason was the long settling times.
But I still want to give this reg a try for the clock of my soundcard.
Do you thing the clock will work OK if the desired voltage is reached before I boot the computer?

Greets,
Klaus
Click to expand...

Yes :)
 
I use it to power the clock and input receiver in my highly modified Behringer DCX digital crossover / pre-amp. The settling time is important and if I just connect the regs directly it will not boot correctly. My solution was simply to keep them powered at all times and when I want to switch the unit 'off' I just switch the regs to a dummy load. It seems to work well.

The only think I notice is that when I switch back to the DCX load the voltage spikes a bit then settles again. e.g. if I want 3.3V it will spike to 3.6V then settle very quickly when I connect the proper load. I'm not sure if this is because of the change in load (my dummy load might be a bit more than the proper one?) or if it is the short time spent in open circuit while the switch changes positions. Any opinions?

preampinternalsfinishedvi8.jpg


A bit messy, but it is hard not to be with well over 150 wires in there! Either way, it sounds very nice. My initial impressions are that it has a more lively dynamic sound than the previous regs I used shown in my last post. No other obvious improvements, but then the other regs were still very good.

cdandprewp6.jpg
 
I am having problems with powering up a digital preamp with TeddyRegs. It is not because the clocks are not running. I tested this, and that was not the problem. It is because the slowly rising supply causes a bad start for the processor, which is in an indeterminate upon power-up. If the processor is in a certain mode, and the external clock pins are held logic high by pull-ups, then shutdown occurs, and the unit will not lock. To get the unit to properly wakeup I either had to install a pull-down resistor on the external clock lines on the processor or use the internal switch to dummy load mentioned before in previous post, which also resulted in short over-voltage period after switching. Caveat: power processors with caution with this reg.
 
Try reducing R3 to 1K (or even less if you need), you'll still get very good results thanks to the second order filter with the ceramic capacitor. Large values of R3 will not suite circuits in which start time is critical. That's the main limitation of this regulator.
 
Hello,
I have an old Naim SNAPS, I want to use it like an HICAP on my cd player.
I think I need two Teddyreg to convert to twin output configuration.
what do you think about?
can you help me?
thank you.
 
teddy_pardo said:
...

Note the use of a heat sink to minimize the temperature effect on the hfe


IMG_2011.jpg

...
Click to expand...

Is it required to heatsink the 317's in a preamp PSU, or is this a "nice to have"? Also, it looks like the TO220 packages are all mounted in a line on a long thin heatsink? I can't find a heatsink with similar dimensions to this - or is it just a piece of square cross-section aluminium?
 
Dr_Evil said:
Is it required to heatsink the 317's in a preamp PSU, or is this a "nice to have"? Also, it looks like the TO220 packages are all mounted in a line on a long thin heatsink? I can't find a heatsink with similar dimensions to this - or is it just a piece of square cross-section aluminium?
Click to expand...

It's a piece of "U" shape cross-section aluminium, and it's optional.
 
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