Re: PS Schematic -Version ? [message #30163 is a reply to message #30159] |
Thu, 20 January 2005 17:49 ![Go to previous message Go to previous message](/forum/theme/AudioRoundTable/images/up.png) ![Go to next message Go to next message](/forum/theme/AudioRoundTable/images/down.png) |
PakProtector
Messages: 935 Registered: May 2009
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Illuminati (2nd Degree) |
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hey-Hey!!!, The PS is very similar. Infunction, it *IS* the same. Here is the basic difference: We're doing full wave instead of full bridge. There is no need for the two SS diodes, and the center tap will be grounded( before we had 250 volts in full bridge ), now we have two half wave supplies on each side of the center tap, this is called full wave.Still going to do a choke input supply, so the cathode(s) of the rectifiers gets attached to the choke( as drawn in the original schematic). here is a discussion on the subject: http://www.tpub.com/neets/book7/27b.htm it shows two SS diodes, the banded end is the cathode, in a vacuum diode, this is the hot part, either directly, as in a 5U4, or indirectly as in a 6CA4. keep asking...the link to ducnan amps has a link for tube data sheets, and a downloadable program to simulate pwoer supply behaviour. regards, Douglas
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6X4 rectifier? [message #30164 is a reply to message #30163] |
Thu, 20 January 2005 18:14 ![Go to previous message Go to previous message](/forum/theme/AudioRoundTable/images/up.png) ![Go to next message Go to next message](/forum/theme/AudioRoundTable/images/down.png) |
colinhester
Messages: 1349 Registered: May 2009 Location: NE Arkansas
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Illuminati (3rd Degree) |
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Are we going with a 6X4? Any ides what the cost of the choke is? I'd like to have a ballpark figure, just so I can get ready for sticker-shock. I downloaded PSU Designer a few weeks back and have been playing with it. Pretty cool.....Colin
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Re: 6X4 rectifier? [message #30165 is a reply to message #30164] |
Thu, 20 January 2005 18:34 ![Go to previous message Go to previous message](/forum/theme/AudioRoundTable/images/up.png) ![Go to next message Go to next message](/forum/theme/AudioRoundTable/images/down.png) |
PakProtector
Messages: 935 Registered: May 2009
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Illuminati (2nd Degree) |
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Welllll, for the rectifier, I'd pick the 6CA4 for top of the 9-pin heap. It is not the least expensive though. Two damper diodes, like 6W4 or 6AX4 are ~$2 each, the 6AX5 is a twin diode like the 6CA4 and is octal. More room around the socket pins for certain, and not too expensive either. For construction ease, a step drill is easy to get that can make a proper sized hole for a 9-pin. A hole saw or hole punch for the octals are the two simplest means. If I had to pick one, I'd say 6CA4. If I weren't slightly over the voltage ratings for this tough little valve, I'd use it for rev. 5. The 8039 choke is ~$75. If you are willing to limit yourself to 10 mA per chanel maximum draw, and not do the shunt reg, you can get by with the little Hammond. The 8039 will leave you room to expand, and will work quite well all the way down to about 10 mA of load, which is ~half the design goal of 10 mA per channel. regards, Douglas
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Re: Schematic - OrCad file [message #30171 is a reply to message #30151] |
Thu, 20 January 2005 21:57 ![Go to previous message Go to previous message](/forum/theme/AudioRoundTable/images/up.png) ![Go to next message Go to next message](/forum/theme/AudioRoundTable/images/down.png) |
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Wayne Parham
Messages: 18752 Registered: January 2001
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Illuminati (33rd Degree) |
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I've made a quick OrCad model and uploaded it into a "Projects" directory. That makes it easy to modify as we make revisions. We can model the circuit with PSpice too. ![](http://www.audioroundtable.com/GroupBuild/Projects/Guinevere.rev.1a.gif)
If you have a copy of OrCad, you can click the image above and download the SCH datafile. If you make changes to the circuit, new mods or whatever, send them to me and I'll upload them and make them available to everyone. This makes a standard format that's easy to use. If you do not have OrCad, you might be interested in the demo version. Click here. I drew this schematic quickly and didn't include the power supply. It isn't much trouble at all, I just have been really pressed for time this week. I'll try to add that later, and that wil let us decide if we're going for the dual-diode full-wave rectifier. Another thing that could be improved is that the proper values for the active components could be used. Right now, the schematic is right but the electrical parameters aren't. As an example, I grabbed a small signal triode but not a 5687 so the tube characteristics would need to be entered for PSpice to work. The diodes are 1N914's or something like that, which aren't the same as LED's. So if we want PSpice to work, we'll need to find the right models for each component or create our own.
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Re: Schematic - OrCad file [message #30179 is a reply to message #30171] |
Fri, 21 January 2005 06:41 ![Go to previous message Go to previous message](/forum/theme/AudioRoundTable/images/up.png) |
Damir
Messages: 1005 Registered: May 2009
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Illuminati (2nd Degree) |
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Good idea, but unfortunately, I don`t have the time/HD space for "OrCad", too much new libraries (tubes!)...huh. Maybe one nice day:-). No problem, if we make some changes, I`ll post a new schematics...
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