I don't think I can drop the resistor further and get under 330VDC for the B+, unless you're saying that the current will run lower than 200mA for the entire circuit?
Kofi
Yes. Set the reporting delay for ~10 seconds. Then, set the simulation time for ~30ms. This will give you a good look at both the amount of ripple, and the shape of the ripple.
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Kofi: A Hammond 270HX based supply would be full wave center tapped; you can change the bridge rectification in PSUD to full wave CT to reflect this. One difference between the two is that you need 2X voltage rated diodes in the FWCT config compared to bridge rectification.
Add V/1386L to your nominal current rating for the choke current rating to allow for ripple current if you are going to use a choke. (V is transformer secondary voltage & L is choke L).
I also used 1200V 8A Fairchild stealth diodes bypassed by 10nf 2Kv caps and a pair of Hammond 270EX transformers in my BH monos (orig schema).
Add V/1386L to your nominal current rating for the choke current rating to allow for ripple current if you are going to use a choke. (V is transformer secondary voltage & L is choke L).
I also used 1200V 8A Fairchild stealth diodes bypassed by 10nf 2Kv caps and a pair of Hammond 270EX transformers in my BH monos (orig schema).
If we need to go film for the first cap, I can only consider Solen 630V PPEs. For the second, I was going to grab a regular old electrolytic and go with that.
Why does a film cap make a difference as the first cap? I always thought the last cap was the one you "heard".
Kofi
Consider using low ESR electrolytics like Panasonic TS-HA or TS-HB or similar in the PS.
Got it... so this is really what should be happening?
Also-- not sure I understand about the calculation... You're saying that I should add 275V / (1386*5H) = .04A or 40mA to the choke rating?
Kofi
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Like maybe a pair of these in series to make an 800V / 240uF cap?
http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=P6844-ND
You may be better served by a single 450V 220u or 330u Pana TS-HB cap. Half the cost, half the ESR, half the space. The TS-HA's max out at 400V, the TS-HBs max out at 450V, and the TS-UPs max out at 500V at Digi-Key. The TS-HA datasheet shows 450V TS-HA's but Digi-Key doesn't sell them. One downside of the TS-UPs is that they are rated at 85deg C instead of 105 deg C.
Which reminds me.......Steve at ApexJr has 450V 390u TS-HA's for $2.50 each presently.
A resistor after your final supply cap is the last thing you want in a power supply. You want the power supply to be low impedance. So size the input cap differently, drop some voltage with a tube rectifier, use a resistor on the input (my least favorite choice), or add a cap after the resistor. You can split the supply at this point, if you worry about channel separation, and use one resistor and cap for each channel.
BTW, single supplies for me. I've never heard an improvement with dual mono supplies. Better to spend your money on one good supply. Channel separation is not that important. The very best phono cartridges get only 30dB (and then only over a limited range). If you want a more complex supply, then make a separate supply for the front end.
Sheldon
Two of those in series will be 60uF at 800v. Capacitors in series reduce the total value, in parallel they add.
Yes, add that to the nominal current draw to size the choke for nominal current draw plus the ripple current. That formula is right out of MJ 3rd ed. for 60hz mains. Also note that the max current requirement is lower with larger L values, since L is in the denominator.
If the choke is undersized for current, you'll lose inductance when the current rating is exceeded.
Got it. Looks like its one supply. Thanks for the explanation. This makes sense to me.
Well of course you're right and I'm dumb and wrong. Get used to that relationship.
Got it. I'll redo the supply and post.
And now... beer.
Kofi
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