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Hoffman Amps Forum image Author Topic: Schematic things and stuff  (Read 6217 times)

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Offline davidwpack

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Schematic things and stuff
« on: March 19, 2018, 01:14:59 pm »
Ello! I finally resolved to download a computer assisted schematic drawing program and chose ExpressSCH. Was this a not-so-good choice? I'm having a terrible time with it. If i screw up, it only seems to have one level of undo so I have to start over. Is there a place to download other symbols as it pertains to tube amps? Or is there another program that's entirely easier? I'm thinking at this point hand drawing them is easier although more time consuming. Maybe I should collect a few more IQ points? Maybe I should have posted this in the schematic forum? Anyways, What do you guys use?

Offline sluckey

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Re: Schematic things and stuff
« Reply #1 on: March 19, 2018, 01:31:39 pm »
Gonna be a learning curve with any piece of drawing software. Give it time. Several people here are turning out very usable drawings with that program. They'll be able to help with program details. I have it installed on my computer but only use it to view other peoples drawings.

I prefer Visio. But that's an even bigger learning curve plus it cost $$$. I started using Visio way back when it only did flowcharts and organization charts. So we kinda grew up together. Visio really started shining once they developed the Professional version with lots of engineering stencils. I'm only using about a tenth of the power of Visio. I'm not really on the Dark Side, just hanging out in the shadows.  :icon_biggrin:
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline davidwpack

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Re: Schematic things and stuff
« Reply #2 on: March 19, 2018, 01:41:30 pm »
I'm thinking about checking out Visio. I really like what you guys are doing with it. Also, I'd like to do layout drawings as well. Everything I've seen done with Visio is really nice. I was thinking I'd try the free stuff first and see how it goes before dropping some cash for Visio. If I'm successful with this, I would say I'll definitely invest in the Visio.

Offline shooter

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Re: Schematic things and stuff
« Reply #3 on: March 19, 2018, 02:51:05 pm »
I cut up my current build into chunks for you.
cut/paste into other files is pita!
open this file, draw box around that you want, use EDIT from toolbar, NOT r-click, say copy, go to file and open new, then R-click paste.
you can also draw box around what you want, edit from toolbar, and "group", then all the parts stay together :laugh:, I've been using .sch since 3-1/2" floppy days :think1:

make sure snap to grid is on, one major downside, if I use .02, and you use .03, and you use pieces from me, they don't snap well!! :cussing:
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Offline davidwpack

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Re: Schematic things and stuff
« Reply #4 on: March 19, 2018, 03:50:30 pm »
Cool!  I'll download this on to my computer when I get back to my house. Thanks man!

Offline DummyLoad

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Re: Schematic things and stuff
« Reply #5 on: March 19, 2018, 04:05:21 pm »
if you use .sch - the default snap to grid makes placing a straight line challenging. use .025" snap and .05" grid and all the parts (metric included) will snap properly.


menu bar "View" >> "Options..." >> Display Grid >> check radio button for "Inches" >> "Display Grid" .050 >> "Snap to Grid" .025 >> OK.


--pete



 

Offline davidwpack

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Re: Schematic things and stuff
« Reply #6 on: March 19, 2018, 04:16:10 pm »
Ok thanks! I'll go in and play around with those parameters. I also switched from a Roland DAW to computer recording software so I'm having a really nightmarish time with computers lately...so is my computer.

Offline jjasilli

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Re: Schematic things and stuff
« Reply #7 on: March 23, 2018, 08:28:15 pm »
I too struggled at first with ExpessSch.  But heck if I can do it anyone can!

Offline tubenit

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Re: Schematic things and stuff
« Reply #8 on: March 24, 2018, 06:26:19 am »
Thing I appreciate about ExpressSCH is that we have a "SCH" library with 100's of editable schematics in it.

http://el34world.com/Forum/index.php?board=12.0

Sometimes it takes me only a few minutes to draw up a schematic change by grabbing an existing schematic and changing something.  An example would be something like a Plexi 25W Mark Huss version using 6V6's but then adding a PPIMV and a 5879 V1.

Also I save large sections as custom components.  In other words,  I have a "one tube reverb",  Fender reverb,  Fender vibrato, PPIMV,  HoSo56 preamp section,   PT & tube rectification and B+ rail section,  LTPI,  Fender tone stack, Marshall tone stack, Dumble tone stack,  James tone stack, etc..........

With respect, Tubenit

Offline turtle441

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Re: Schematic things and stuff
« Reply #9 on: March 24, 2018, 09:05:27 am »
I like ExpressSCH, but to each their own.  I use DIYLayout Creator for layouts.  Not as fancy as Visio, but much easier to figure out.  If you dig around a bit, you can create custom parts in ExpressSCH.  I think I had to create some triodes and pentodes when I first started using it. Stealing someone else’s part is probably easier.

Offline davidwpack

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Re: Schematic things and stuff
« Reply #10 on: March 24, 2018, 09:53:08 am »
I'm starting to get used to it. I've been editing the stuff Shooter sent for me. Thanks again! I'm trying to figure out how to cut a circle in half and make a paralleled triode. Other than that it's starting to sink in. I think I'll like it with a little more time with it.

Offline shooter

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Re: Schematic things and stuff
« Reply #11 on: March 24, 2018, 10:29:04 am »
Quote
how to cut a circle in half
on the left TB there is a segmented circle, select it and pick 1/2 circle.   you can select size also.  I like using 1/4 circle radius .08 to use where lines cross each other
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Offline davidwpack

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Re: Schematic things and stuff
« Reply #12 on: March 24, 2018, 10:43:43 am »
Oh ok gotcha. I think I like this. I just wish it had one of those little eraser tools like on Photoshop.

Offline tubenit

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Re: Schematic things and stuff
« Reply #13 on: March 24, 2018, 11:34:22 am »
Here are 3 more sets of custom components I use.   Just group a section and save it.  Lots of useful stuff to draw up a custom schematic quickly.

With respect, Tubenit

Offline davidwpack

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Re: Schematic things and stuff
« Reply #14 on: March 24, 2018, 11:45:17 am »
Cool!. I'll get those as soon as I get back home in the morning. Thanks man!

Offline tubeswell

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Re: Schematic things and stuff
« Reply #15 on: March 24, 2018, 02:51:14 pm »
JSchem is simple, intuitive and has several platforms including Mac. http://jschem.bplaced.net


The library components can be expanded (and the basic line and curve tools are there to draw you own components if you have the patience), and you can group components into 'macros' for adding to the library so you can instantly load main amp segments like the tone stack/input stage, PI stage, or output stage etc , and you can save the schematic as a .shem file or .pdf .jpg .png etc. And you can add components created in/for ExpressSCH to the library.


I use it all the time - here's some I've done
« Last Edit: March 24, 2018, 04:57:25 pm by tubeswell »
A bus stops at a bus station. A train stops at a train station. On my desk, I have a work station.

Offline davidwpack

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Re: Schematic things and stuff
« Reply #16 on: March 24, 2018, 05:12:02 pm »
Yeah, I've been looking at that some too. Thanks.

Offline davidwpack

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Re: Schematic things and stuff
« Reply #17 on: May 28, 2018, 08:56:20 am »
Ello! I've finally had some time to sit down with this and am attempting to draw up my last build. I've got 5 consecutive days off in my rotation so I should be able to finish it up. I've got a couple more questions hopefully someone will have an answer or 2 for.
1. Is there a way to delete excess points/dots? Whenever I change angles with a wire it leaves a connection point. Maybe I'm not doing it right.
2. Easier way to draw the curve/hump thing when wires cross? The only way I've figured to do it so far is to insert a half circle and decrease the size. This leaves 2 more connection points when you insert it  Thought maybe there was a different way of doing it.
I'll attempt to post my progress so far. I've got a master volume after the tone stack and prior to the PI. I'm not sure if it's schematically correct. Anyways...I'll try to post my progress so far here in a bit.

Offline davidwpack

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Re: Schematic things and stuff
« Reply #18 on: May 28, 2018, 08:59:33 am »
Schematic so far...

Offline davidwpack

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Re: Schematic things and stuff
« Reply #19 on: May 28, 2018, 09:01:27 am »
Thought it would post a picture. Apparently it has to be downloaded. Anyways...dave

Offline John

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Re: Schematic things and stuff
« Reply #20 on: May 28, 2018, 10:41:12 am »
Make your own jumper and save it as a custom component.


Use a small half circle
Add a pin at each end.
Highlight it (it turns blue) with your cursor.
Click on Component>Group to make Component.
It'll give you a pop up which I ignore, just click OK.
Then, while leaving it still highlighted, click Component>Save as custom component


I've made resistors, caps, etc. that I use in layouts all the time. Thing to remember is, you can't include a "wire" in your custom component. You have to use the line tool instead.
Tapping into the inner tube.

Offline davidwpack

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Re: Schematic things and stuff
« Reply #21 on: May 28, 2018, 10:52:25 am »
Oh, ok. Thanks!!! I'll do that right now. I need to try to make an arrow too. Mine look all disproportionate and stupid. And none of them look the same. Thanks again!

Offline John

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Re: Schematic things and stuff
« Reply #22 on: May 28, 2018, 10:56:37 am »
Once you get the hang of making your own symbols and comps, it's really pretty fast. And you can save as many into your "custom components" folder in the component manager as you want.
Tapping into the inner tube.

Offline sluckey

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Re: Schematic things and stuff
« Reply #23 on: May 28, 2018, 11:02:39 am »
I don't use line jumps in my schematics. Those curved line jumps will get messy in a hurry as your schematic becomes more complicated. I use the straight cross-over for lines that do not actually connect and I always put a dot at all lines that do connect.

There are two common methods of drawing crossing lines. Method 1 simply draws the lines straight across with no "jump humps". You must use dots for ALL connections. Method 2 uses "jump humps" and there is no need to use any dots. After looking at high density schematics (especially for digital logic circuits) I much prefer method 1 for it's clean look. But you need to chose one method or the other and don't mix the two methods. There are a lot of sch schematics floating around that don't use line jumps and also don't use dots at intersections. Now that is really confusing. Sometimes it's easy to know where the dots should be. Sometimes it's very confusing.

Whichever method you chose, just be consistent. And don't mix the two methods.
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline davidwpack

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Re: Schematic things and stuff
« Reply #24 on: May 28, 2018, 11:15:15 am »
Oh good. It'll be a lot easier without the humps. I guess I just assumed that it was a rule to include them for a proper official-like schematic. I'll definitely omit them. Thanks!

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Re: Schematic things and stuff
« Reply #25 on: May 28, 2018, 04:45:28 pm »
here's a quicky of both, the "hump" I set size to .08, select the small circle part and rotate as needed.  Steve's correct, pick one, I was born with schematic all humpin, so I stayed with it  :l2:
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Offline davidwpack

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Re: Schematic things and stuff
« Reply #26 on: May 28, 2018, 06:19:01 pm »
Hey, thank ya! I think I'll be finished with it this evening. I'll probably do a separate voltage sheet rather than trying to get all those numbers typed in there.

Offline PRR

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Re: Schematic things and stuff
« Reply #27 on: May 28, 2018, 08:03:08 pm »
> humps. I guess I just assumed that it was a rule to include them for a proper official-like schematic.

There are at least 4 "standard" ways to notate crossovers, and dozens of variants.

_I_ like humps. I have seen a few plans where a connecting dot was omitted and the plan would smoke if built as printed. Moreover cross-lines tend to get blurry on FAXes, scanners, and when (sinfully) JPEGed, so I'm squinting "is that a dot or not??"

However my main concern is that it be UNAMBIGUOUS. Secondarily, without taking a poll of all the crossings to figure out what "standard" the draftsman was working to.

> Thought it would post a picture.

The .SCH file is unknown to web-browsers. The Web is full of pretty-girl images so they all support JPEG, and GIF more for historical images (though GIF is eXcellent for schematics); PNG for political reasons. The Web is full of sales-sheets in PDF so browsers have (uneasy) linkings to PDF readers. Several types of sound and movie files play in browsers. .SCH is obscure and not browser-supported without insane scripting.

Does your .SCH tool have a "File, Export As, ...." option? Many do. This gives an image file in some popular format. This can not be Edited in the SCH editor, but also does not need the SCH tool just to _see_ it. Since I have misplaced my JSCHEM icon, a nice GIF or PDF is preferable for me here.

Offline shooter

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Re: Schematic things and stuff
« Reply #28 on: May 28, 2018, 08:54:02 pm »
Quote
is unknown
Sorry, I just past him something he could grab for his "collection", Steve's pic is way better!   :laugh:
for public consumption I go from .sch to .bmp to .jpg, aw well, free is free
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Offline davidwpack

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Re: Schematic things and stuff
« Reply #29 on: May 29, 2018, 03:21:09 pm »
I believe it's finished! This amp has a lot of head room/volume. I recommend the bright cap. This amp is the first amp I've ever had that gives me use of my guitar's tone control. All my other amps my tone is always on 10. I'd equate this amp (or at least find it remarkably similar) to my Ampeg B25-B with the channels patched together. Probably my favorite amp out of any amp I've ever played through. I've got a hand-drawn layout if anyone wants it. I was going to export this as another file type so that I could post it as a picture but the only options were "Bitmap" and "Metafile"??? Anyways, I've looked over it a couple times and couldn't find errors other than I'm not sure I drew the bright switch correctly. I've got it on a push/pull volume pot so I think I may have drawn it wrong. Anyways, I'll try to post the completed version again. P.S.Thanks for everybody's help!
« Last Edit: May 29, 2018, 03:29:27 pm by davidwpack »

Offline sluckey

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Re: Schematic things and stuff
« Reply #30 on: May 29, 2018, 04:11:37 pm »
You need to get Irfanview. It's a free graphics program that is easy to use and does a lot of stuff. You could have used it to create a web friendly image of your schematic. Just export your ExpressSCH schematic to BMP file. Then open in Irfanview and save as PNG file. Upload the PNG file to the forum. It took me under 5 minutes to download your sch file, open it, export to a BPM, open the BMP and save as a PNG with Irfanview, type this message, and attach the PNG image.

     https://www.irfanview.com/


BTW, your schematic is looking good, but I noticed a couple of errors that should be fixed. The bias diode is backwards. And the PT and rectifier wiring is all messed up. The 5VAC winding should be completely separate (just like the 6.3V filament winding) from the HT winding and should connect to pins 2 and 8. HT windings should connect to pins 4 and 6. Look at some of tubenits drawings to see how to do it properly.
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline davidwpack

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Re: Schematic things and stuff
« Reply #31 on: May 29, 2018, 05:12:53 pm »
Good lord. I blame sleep deprivation. :icon_biggrin:  I think I got it this time. Thanks for showing me how to convert the file. I'll try it.

Offline davidwpack

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Re: Schematic things and stuff
« Reply #32 on: May 29, 2018, 05:13:43 pm »
Ha! Awesome!

Offline sluckey

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Re: Schematic things and stuff
« Reply #33 on: May 29, 2018, 07:44:55 pm »
 :thumbsup:
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline Sonny ReVerb

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Re: Schematic things and stuff
« Reply #34 on: May 30, 2018, 03:34:53 pm »
It's also helpful to add some notes concerning the components used - resistor watt ratings, cap voltage ratings, particular materials (e.g. metal oxide, metal film, carbon film, silver mica, PIO ...), etc. so someone can recreate your masterpiece 50 years from now. Here's a piece of a schematic with some examples from a famous manufacturer ;)


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Re: Schematic things and stuff
« Reply #35 on: May 30, 2018, 10:09:11 pm »
The two 1 Ohm cathode resistors should be separate, not connected together.

The amp will work the same, but you can't get separate readings on each tube (the main idea!), only some average of both.

Offline davidwpack

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Re: Schematic things and stuff
« Reply #36 on: May 30, 2018, 10:26:54 pm »
Thanks guys. Yeah I still need to embellish it, add a couple things, take out a couple things. I'll post it in the schematic area with a layout when I feel like I have it ironed out.

 


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