Re: Where did the current go?
Just a word of thanks, Duncan for making such a useful piece of software available gratis. I've used it as necessary for many years; it beats faffing around finding suitable models for Spice, and for sure beats using Schade's paper and his graphical method. Actually back in the day Schade was how I used to do this stuff before free versions of Spice were available, and long before your software was available.
Cheers!
Craig (in the UK)
------ Original Message ------
Date 17/11/2023 08:47:40
Subject Re: [duncanampspsud] Where did the current go?
Hi John,
This is a PSUD2 problem rather than a mismatch in setups. Kirchoffs first law is quite clear, the currents going into a node should equal the currents coming out.
To speed up and simplify simulations, PSUD2 breaks Kirchoff's laws and, as such, has been broken as designed for over 20 years. Most of the time it's reasonably close, and can get away with it but there are times when something comes up that diverges to a really whacky result. Wasn't really expecting it on such as simple example as the one you've illustrated.
For your example above, all three currents should be identical at all times. Therefore, the mean/min/max should all be the same too.
The problem stems from the way PSUD2 tries to balance the network of components, so it's not fixable without a total rewrite, which is why I started on PSUD3. This uses a matrix solver which is similar to the SPICE family and will respect both of Mr Kirchoff's pearls of wisdom.
Unfortunately PSUD3 has taken a pause right now, I recently put out a beta to a half dozen participants to try it out. It needs more work in the way the user interface operates, and was messing up their installations in some instances which isn't acceptable. I'll get more time to work on it during the Christmas break so should be able to incorporate their feedback and introduce it to a wider audience. Will post on here when it's good to go.
Regards,
Duncan
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Re: Where did the current go?
Hi John,
This is a PSUD2 problem rather than a mismatch in setups. Kirchoffs first law is quite clear, the currents going into a node should equal the currents coming out.
To speed up and simplify simulations, PSUD2 breaks Kirchoff's laws and, as such, has been broken as designed for over 20 years. Most of the time it's reasonably close, and can get away with it but there are times when something comes up that diverges to a really whacky result. Wasn't really expecting it on such as simple example as the one you've illustrated.
For your example above, all three currents should be identical at all times. Therefore, the mean/min/max should all be the same too.
The problem stems from the way PSUD2 tries to balance the network of components, so it's not fixable without a total rewrite, which is why I started on PSUD3. This uses a matrix solver which is similar to the SPICE family and will respect both of Mr Kirchoff's pearls of wisdom.
Unfortunately PSUD3 has taken a pause right now, I recently put out a beta to a half dozen participants to try it out. It needs more work in the way the user interface operates, and was messing up their installations in some instances which isn't acceptable. I'll get more time to work on it during the Christmas break so should be able to incorporate their feedback and introduce it to a wider audience. Will post on here when it's good to go.
Regards,
Duncan
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Where did the current go?
Hi. I've been poking around trying to explain a 10volt difference between PSUD2 and LTSpice results for an EZ81 based power supply. It's not a big deal (the amp's been working for years) - I'm just trying to understand the use of both tools for Power Supply design. I've been assuming that the difference is in the models of the EZ81. I kept trimming the design down until I reached the attached configuration. The Transformer current matches the Diode current, but the Resistor current (Mean) is 7mA less. What am I missing? 
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Re: Capacitors in series to increase working voltage question
I would say that the 1mA or so of current through the balancing resistors is insignificant. You could use a 100uF 500v capacitor instead, but it would probably cost more than the two 250v ones.
The 6N1P is very different from the 6922, apart from having the same pinout. It has much higher anode impedance and likes a higher voltage. It looks more like a higher-gain 6CG7 substitute to me, but does not sound anything like as good. I'd stick with the 6922/E88CC.
Edit: You will need to check that the 6922 can provide enough voltage swing to drive the EL34 without distorting.
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Re: Capacitors in series to increase working voltage question
Hi Paul, I believe you asked about the voltage divider resistors in parallel with the series resistors. While it is a small current going through them it still presents a load on the supply. I would not ignore them
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On Nov 13, 2023, at 2:46 PM, Duncan Munro <duncan@...> wrote:
?Hi Paul,
Yes, just use half the value for the capacitor and you'll have the right answer. Any ESR (Equivalent Series Resistance) in the cap should be doubled.
Regards,
Duncan
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Re: Capacitors in series to increase working voltage question
Hi Paul,
Yes, just use half the value for the capacitor and you'll have the right answer. Any ESR (Equivalent Series Resistance) in the cap should be doubled.
Regards,
Duncan
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Capacitors in series to increase working voltage question
Hi, apologies if this has been asked before, to model capacitors in series I assume you model one capacitor at half the value. For example two 220uF caps in series would be modelled as one 110uf Cap. For the resistors around each cap for current flow I assume you disregard as they are only there for the series connected caps. Also, has anyone modeled the Audion Edison 60 amp running? EL34 and 6H1N valves as I'm have a few power supply problems mainly due to smoothing capacitor voltage and I think noise induced by failing caps (two 220uf 250v in series) at the EL34 and then single 220uf 450v for the 6H1N. I'm running E88C instead of the 6H1N's. I've pasted in one of lefthand channel including power supply
Paul
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Re: PSUD3 Windows Beta / Preview edition
Only if your VIC-20 runs Windows 7/8/10/11 in 64 bit... :)
Regards,
Duncan
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Re: PSUD3 Windows Beta / Preview edition
I'm still using a VIC-20. Is it compatible?
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On Oct 18, 2023, at 2:45 AM, Duncan Munro <duncan@...> wrote:
?"I was holding back to be sure every eager body had a chance"
Hi Paul, you've been a MASSIVE contributor to this group in terms of technical input to me as the designer, and in assistance/advice to countless others who are finding their way with PSUD. I would be delighted for you to be on the first group.
So far we've got 5 names, if we don't get 10 by Sunday 22nd I'll just put the limited Beta out with the numbers we have and aim to put a more general release out approximately 2-4 weeks later depending on feedback and progress.
Thanks all for your input and assistance with this.
Regards,
Duncan
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Re: PSUD3 Windows Beta / Preview edition
Hi Marc, have added you to the list.
Regards,
Duncan
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Re: PSUD3 Windows Beta / Preview edition
On the other end of the scale is myself. ? I’ve toyed with the program a bit but I’m a “nube” to electronics.? I’m in the middle of building a couple of tube projects that will need new power supplies. BUT I wanted the real “pros” to have the first go as they will give you high quality feedback. ??I’d be happy to dig in. I’m familiar with alpha and beta testing in general but with database type programs. ? I’d be honored to give the new version a spin if you’d like to include me…..but if you don’t that’s ok too, I will not be offended. ? Marc ? ? Marc Chavez FCSI AIA Member Emeritus 5643 3rd Ave NW Seattle WA 98107 Cell 206-300-3511 ?
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Re: PSUD3 Windows Beta / Preview edition
"I was holding back to be sure every eager body had a chance"
Hi Paul, you've been a MASSIVE contributor to this group in terms of technical input to me as the designer, and in assistance/advice to countless others who are finding their way with PSUD. I would be delighted for you to be on the first group.
So far we've got 5 names, if we don't get 10 by Sunday 22nd I'll just put the limited Beta out with the numbers we have and aim to put a more general release out approximately 2-4 weeks later depending on feedback and progress.
Thanks all for your input and assistance with this.
Regards,
Duncan
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Re: PSUD3 Windows Beta / Preview edition
Hi, just wanted to say, very happy to see this development and how close it looks to be getting. I'm not savvy enough to beta, but am excited about the potential to my toolbox. Since 1985 I've beta tested for a lot of companies doing graphic layout programs and associated accessories and drivers, mostly on MacOS, but occasionally on Windows based software. I was pushed into learning schematic capture and PCB layout software back round 2010, accompanied by a lot of work in 2D software for creating layouts for sheet metal work to do with designing and building chassis, which has grown into generating gcode and running a CNC router machine for sheet metal and PCB prototypes. Still heavily involved in the design of basic tube audio preamps for recording, and somewhat backwards, finally jumping more into the area of power supplies as I veered off for the past year when I decided I couldn't afford to buy a vintage Fender guitar amp - so armed with old schematics, have built myself a Vibro Champ clone with mods and in progress with a Princeton reverb and a few other designs from the 60s. I picked up quite a few books on power supplies that I'm finally ready to crack open, which is why I'm excited to receive the email from this conversation this evening! Timing couldn't be better!! All the best to everyone, I'll keep an eye on the discussion -? so happy to see tube rectifiers in the software!!!
Donn
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Re: PSUD3 Windows Beta / Preview edition
On 10/15/2023 10:35 AM, Duncan Munro wrote: avoid taking up a slot I was holding back to be sure every eager body had a chance. But yes I would like to see, comment, and suggest. I have much experience in beta-busting. I have done power supplies with ARRL Handbook and slide-rule, also SPICE and PSUD. I have Win7 and Win10 on hand. -Paul
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Re: PSUD3 Windows Beta / Preview edition
Designing a couple supplies atm and love to try version 3! ? ? ? ? ? ? ? ?Best Regards. Mark Nelson
On Sun, Oct 15, 2023 at 10:35?AM Duncan Munro < duncan@...> wrote: Hi all, I'm still working on PSUD3 but thought I would pass it out in Beta form for comment to a small number of participants to get feedback on any potential major flaws. I'd like to keep the initial batch small as there will likely be numerous comments; many comments times many people will turn it into a circus, so I'd say about 10 people would be a good number to feed back initially on the very raw version. If the wheels don't fall off in grand style, this number could be increased after a couple of weeks.
So... the next 10 people to reply to this message saying they want to be involved will receive a Beta copy of the software with a 30 day lifespan for them to have a look at and feed back via a private email list. It will just be Windows to start with; it makes sense to avoid fighting fires on multiple fronts until the basic structure is in place and correct. What I'm looking for is people who will run a bunch of different power supplies through, check accuracy / differences against PSUD2, and above all feed back the comments. Please avoid taking up a slot on the initial program if you've no in interest in doing that or just want to see what PSUD3 looks like out of curiosity.
Some features, such as chart printing, are incomplete and the help file is probably more comedy than help right now, so please bear this in mind :)
If you need a refresher on what PSUD3 is meant to look like, there's a video here ->?
Regards,
Duncan
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Re: PSUD3 Windows Beta / Preview edition
Hi Duncan,
yes! I'm interested in this! I constantly use PSUD2 so I can
compare with the new one and let you know.
Best regards,
Fabio
Il 15/10/2023 16:35, Duncan Munro ha
scritto:
toggle quoted message
Show quoted text
Hi all, I'm still working on PSUD3 but thought I would pass it out
in Beta form for comment to a small number of participants to get
feedback on any potential major flaws. I'd like to keep the
initial batch small as there will likely be numerous comments;
many comments times many people will turn it into a circus, so I'd
say about 10 people would be a good number to feed back initially
on the very raw version. If the wheels don't fall off in grand
style, this number could be increased after a couple of weeks.
So... the next 10 people to reply to this message saying they want
to be involved will receive a Beta copy of the software with a 30
day lifespan for them to have a look at and feed back via a
private email list. It will just be Windows to start with; it
makes sense to avoid fighting fires on multiple fronts until the
basic structure is in place and correct. What I'm looking for is
people who will run a bunch of different power supplies through,
check accuracy / differences against PSUD2, and above all feed
back the comments. Please avoid taking up a slot on the initial
program if you've no in interest in doing that or just want to see
what PSUD3 looks like out of curiosity.
Some features, such as chart printing, are incomplete and the help
file is probably more comedy than help right now, so please bear
this in mind :)
If you need a refresher on what PSUD3 is meant to look like,
there's a video here ->?
Regards,
Duncan
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Re: PSUD3 Windows Beta / Preview edition
Count me in.
I was a programmer for over 40 years and electronic engineer... if
that's worth anything.
On the flip side, I' out of town for 10 days starting today
- Ian
On 10/15/2023 07:35, Duncan Munro
wrote:
toggle quoted message
Show quoted text
Hi all, I'm still working on PSUD3 but thought I would pass it out
in Beta form for comment to a small number of participants to get
feedback on any potential major flaws. I'd like to keep the
initial batch small as there will likely be numerous comments;
many comments times many people will turn it into a circus, so I'd
say about 10 people would be a good number to feed back initially
on the very raw version. If the wheels don't fall off in grand
style, this number could be increased after a couple of weeks.
So... the next 10 people to reply to this message saying they want
to be involved will receive a Beta copy of the software with a 30
day lifespan for them to have a look at and feed back via a
private email list. It will just be Windows to start with; it
makes sense to avoid fighting fires on multiple fronts until the
basic structure is in place and correct. What I'm looking for is
people who will run a bunch of different power supplies through,
check accuracy / differences against PSUD2, and above all feed
back the comments. Please avoid taking up a slot on the initial
program if you've no in interest in doing that or just want to see
what PSUD3 looks like out of curiosity.
Some features, such as chart printing, are incomplete and the help
file is probably more comedy than help right now, so please bear
this in mind :)
If you need a refresher on what PSUD3 is meant to look like,
there's a video here ->?
Regards,
Duncan
|
PSUD3 Windows Beta / Preview edition
Hi all, I'm still working on PSUD3 but thought I would pass it out in Beta form for comment to a small number of participants to get feedback on any potential major flaws. I'd like to keep the initial batch small as there will likely be numerous comments; many comments times many people will turn it into a circus, so I'd say about 10 people would be a good number to feed back initially on the very raw version. If the wheels don't fall off in grand style, this number could be increased after a couple of weeks.
So... the next 10 people to reply to this message saying they want to be involved will receive a Beta copy of the software with a 30 day lifespan for them to have a look at and feed back via a private email list. It will just be Windows to start with; it makes sense to avoid fighting fires on multiple fronts until the basic structure is in place and correct. What I'm looking for is people who will run a bunch of different power supplies through, check accuracy / differences against PSUD2, and above all feed back the comments. Please avoid taking up a slot on the initial program if you've no in interest in doing that or just want to see what PSUD3 looks like out of curiosity.
Some features, such as chart printing, are incomplete and the help file is probably more comedy than help right now, so please bear this in mind :)
If you need a refresher on what PSUD3 is meant to look like, there's a video here ->?
Regards,
Duncan
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Re: Where to download psud2 ??
Good tip.
The files ended up here due to a restriction on hosting certain files on duncanamps.com when the hosting moved provider about 3 years ago.? I think I've got round this now so should be able to put the files back in the normal place at?
This won't happen until December when I get some time to revamp the whole duncanamps site; it's long overdue...
Regards,
Duncan
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Re: Where to download psud2 ??
It might be worth pointing out on the front page that people need to join the group to see the file section and thus download the file. I too couldn't find it, even after read your message here, because I hadn't joined the group. I was thinking "What file area?" (I don't use google.io much, obviously).
But I suspect noting that on the home page will be helpful to people who got here the way I did: Via the old site.
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Marc Chavez
Paul Reid
Ian Eales