Electronic diagramming tools with power and output transformer symbols

Hi,

I've search diyAudio and googled extensively. Tried many free tools and trials of commercial tools (SchemiIt, EasyEDA, Visio, SmartDraw, DipTrace, KiCad EDA, Sketchup, ExpressSCH and many others.

Many have tubes but they all fall short when it comes to transformer support. Others are simply overwhelming with no intuitive way to get started.

Free tools tend to be associated with PCB layout and lack of transformer support isn't surprising.

I've read that Visio has support for building transformer symbols but the Pro version required is expensive.

So how are folks producing the circuit diagrams I'm seeing in these forums?
 
I use Vectorworks. It is a commercial CAD program and not cheap. It comes with tube symbols. I wasn't happy with them so drew my own. The same could be done with any CAD sw.

Here is a 10 year old example.

elCheapo-23jun06-map.gif


dave
 
Thanks for all the replies. I've been using LTSpice up to the driver stage to simulate a Williamson design! I didn't realise you could create a transformer like that.
I'll persevere.

The small secret is you don't need to create output transformer model (at least in this particular case) :)

Put necessary number of inductors (L1, L2, ... Ln) with inductance value in Henry, and link them with coupling factor (K1 L1 L2 ...Ln 1.0). Coupling factor 1.0 corresponds to ideal transformer with zero leakage inductance. Even with that model, results of simulation are surprisingly close to reality.
Then, if necessary, adjust coupling factor according to measured leakage inductance:
Coupling factor K = SQRT(Ls/Ls + 1)

Of course, inductance is not constant, and there are other parasitic parameters like stray capacitance, yet they are vary from one model/manufacturer to another, and with ideal model you can check problems with tube/transistor circuit alone.

I modelled Williamson upon suggestion from articles
"Improving Williamson Amplifier", Talbot Wright
"Modernize your Williamson", David Hafler

IMHO, even after tweaking, Williamson is not the best PP circuit around.
 
My favourite PP schematic is GEC 88-50 amplifier.
Its reasonable simple, very stable, and I've got 60W from it with very low distortions.

I have nothing against Mullard 520 derivatives, like Marantz 8, Citation II, Sansui AU111, and countless number of others.
in fact, it was first PP amp I've built.

However, I spent a lot of time fighting oscillation and instability, so I may have some prejudice against Mullards.
 

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Just to return to the original question for a moment. I use Visio 5 that I bought on epay for about $10. There is no need to purchase an expensive new version to draw schematics. If you have to you can create your own symbols and save them as models.

Thanks. I have Visio Standard 2010. Since there was no Engineering template I thought I'd have no electronic symbols. I'll investigate further.
 
My favourite PP schematic is GEC 88-50 amplifier.
Its reasonable simple, very stable, and I've got 60W from it with very low distortions.

I have nothing against Mullard 520 derivatives, like Marantz 8, Citation II, Sansui AU111, and countless number of others.
in fact, it was first PP amp I've built.

However, I spent a lot of time fighting oscillation and instability, so I may have some prejudice against Mullards.

Thanks again. My plan was to build http://www.diyaudio.com/forums/tubes-valves/158322-my-kt88-williamson-amp-build.html as 2 monoblocks. I have the power transformer with the 80V tap now so I'll stay with that.