Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: Esquirefreak on April 21, 2024, 04:18:19 am

Title: My first schematic
Post by: Esquirefreak on April 21, 2024, 04:18:19 am
I cut my finger when cooking the other day, so no guitar for some time.

I found an inexpensive software for drawing schematics and sat down yesterday trying to figure it out.

I just want to hear your opinions. Bear in mind that this is my first time drawing and I've only done it for one day. So go easy on me.

About the amp:
I wanted something that can do big cleans but also some growling brownface distortion. It works really well. Very low noise floor even with the gain turned up. I can choose how hard the PI is being pushed. The variable slope resistance is useful when driving the amp more/less and when switching between humbuckers and singlecoils.

So, I know that the amp came out great, but I'm a beginner at drawing schematics. What could/should I change or do differently?

Feedback is much appreciated!

/Max
Title: Re: My first schematic
Post by: sluckey on April 21, 2024, 06:11:19 am
Looks good. Logical flow and easy to read. My only suggestion is to consistently use dots for connections.
Title: Re: My first schematic
Post by: Esquirefreak on April 21, 2024, 07:01:07 am
Yeah, the software (for some reason) chose to use dots sporadically when connecting the lines. That's why it's not perfectly consistent.

I sent it to a friend who's an engineer and his complaints were:

Diagonal lines, missing voltage notations and suggested I should use arrows instead of the boxes showing connection points.

I will be doing a later revision, changing those minor things soon.

Thank you, Sluckey 👍

/Max
Title: Re: My first schematic
Post by: tubenit on April 21, 2024, 07:22:30 am
I think you did a fine job for 1st attempt. 


Just a personal preference thing but I like using boxes just like you did in the schematic much more than using arrows. I find boxes easier to follow.


With respect, Tubenit
Title: Re: My first schematic
Post by: green drake on April 21, 2024, 10:00:13 am
I’m new to amps but was an electrical designer for many years (mostly power distribution)
That’s a solid first attempt (heck, a solid tenth attempt :-))very good flow and organization. Boxes, arrows, doesn’t matter as long as there is consistency and symbols can’t be confused.
You could align symbols horizontally and keep diagonal lines short and with consistent angles, but really, I think your schematic is well done. It’s clear and easy to follow which is most important.
Title: Re: My first schematic
Post by: Esquirefreak on April 21, 2024, 10:06:42 am
Wow, thanks, that means alot!

/Max
Title: Re: My first schematic
Post by: Esquirefreak on April 21, 2024, 11:29:05 am
I'll get back with some gut shots when I take it out of the cabinet next time.

The faceplate is made with dry transfer lettering. So it's not perfect, but it's hand made.

I tried to build with whatever parts I had on hand at the time.

EDIT: I'll change the pot labels in the schematic so that they match the faceplate.

/Max
Title: Re: My first schematic
Post by: acheld on April 21, 2024, 03:23:43 pm
+What everyone is sayin'.  Looks nice.

Which program did you use?   Just curious -- I have a longstanding obsession regarding inexpensive computer programs for schematics . . .
Title: Re: My first schematic
Post by: Esquirefreak on April 21, 2024, 03:31:59 pm
I used "ElectricDesignPro". Since my only computer is a Macbook, the list of alternatives is slightly narrower than the PC offerings.

The price I paid would probably translate to ~$30.

/Max
Title: Re: My first schematic
Post by: pdf64 on April 21, 2024, 05:23:27 pm
Looks good, well done!
The OT secondary switch looks a bit off, like there's an unused switch position.
Title: Re: My first schematic
Post by: Esquirefreak on April 22, 2024, 12:45:38 am
Well spotted! It's originally a 4 position switch. I might create my own switch symbol, copying another design.

/Max
Title: Re: My first schematic
Post by: tubeswell on April 22, 2024, 03:58:12 am
I used "ElectricDesignPro". Since my only computer is a Macbook, the list of alternatives is slightly narrower than the PC offerings.

The price I paid would probably translate to ~$30.

/Max


JSchem is free (and there is a Mac version)


http://jschem.bplaced.net/ (http://jschem.bplaced.net/)
Title: Re: My first schematic
Post by: Esquirefreak on April 22, 2024, 04:45:34 am
Ah, darn it, I already bought the other software  :BangHead:

/Max
Title: Re: My first schematic
Post by: acheld on April 22, 2024, 10:16:48 am
Quote
I already bought the other software

I'd consider trying JSCHEM.   It's a lot simpler than ElectricDesignPro.  I like the fact that it has been stable for years now, and does exactly what I tell it to do.   But -- it does not produce nearly as pretty schematics as does Visio or some of the high end schematics editors.   If you're happy and proficient with EDP, stick with it.   

The real investment is the time spent mastering any software program. 
Title: Re: My first schematic
Post by: Esquirefreak on April 22, 2024, 10:40:42 am
At this point I feel like I'll try to master (or learn, to be honest) drawing and reading schematics before doing software comparisons. It's enough of a challenge right now 😄

But thanks for the recommendation and I'll check out the software anyway 👍

/Max
Title: Re: My first schematic
Post by: Esquirefreak on April 24, 2024, 04:36:59 am
So, revision B and some gut shots.

Wall voltage at home is 5-10 volts lower than on my work bench, so it's biased with the higher voltages in mind.

Any further improvements I should do on the schematic? For the first time in quite a while, I feel like I'm learning new stuff. It's really fun.

/Max
Title: Re: My first schematic
Post by: sluckey on April 24, 2024, 07:09:25 am
Nice improvement. Missing a connection dot on V2 pin 1. The resistor symbols look huge to me. Do you have control over the size?

Good looking build. I've always wanted to try a variable slope or shape control but never did. Do you find your shape control to be useful?
Title: Re: My first schematic
Post by: Esquirefreak on April 24, 2024, 08:00:50 am
Aaah. I knew I missed something! The resistor symbol size was preset so I just went with that one. I will probably crimp it and save as a custom shape. If I mark all the resistors and crimp them simultaneously, it won't be too much work. I think the diode symbol size is way too big as well.

I find the variable slope VERY useful. High slope, scoop mids, EQ at noon and low preamp volume makes for a nice fender-ish clean.

Low slope, flat mids, roll down the bass, sharp bright cap and volume at 2 o clock and it really grinds. I think it sounds like its own thing. Kinda like a mix between a brown Bassman, a 2203 and a tweed amp. And how hard you drive the PI is another variable. I might make a Youtube video of it.

I'll get the little details corrected later today. Thanks!

/Max
Title: Re: My first schematic
Post by: Esquirefreak on April 25, 2024, 02:48:22 am
I'm gonna call it done by now.

/Max
Title: Re: My first schematic
Post by: tdvt on April 25, 2024, 06:28:07 am
The final drawing looks great & interesting extras as well.

I am intrigued by the variable slope, I will have to try that.
 
Title: Re: My first schematic
Post by: Esquirefreak on April 25, 2024, 06:34:48 am
Thanks!

I first tried it on my 5F6A-ish build but with a fixed 56k resistor in series with a 50k log pot and really liked it. I think that the 100k linear pot and 22k resistor makes for a broader, yet useful sweep.

/Max
Title: Re: My first schematic
Post by: mresistor on April 25, 2024, 10:55:06 am
That's a very good looking amp!
Title: Re: My first schematic
Post by: Esquirefreak on April 26, 2024, 02:49:26 am
Last pic, I promise!

/Max
Title: Re: My first schematic
Post by: mresistor on April 26, 2024, 09:02:40 am
LOL where's the knobs for the little head to the left?
Title: Re: My first schematic
Post by: Esquirefreak on April 26, 2024, 09:09:56 am
Had to borrow for something else...  :laugh:
Title: Re: My first schematic
Post by: wsscott on April 27, 2024, 02:43:46 pm
Really nice build too!  Great looking amp inards!  Did you also create a Layout of your schematic?  I've done that one time, based on an existing schematic that had been modded, and that was a tough chore.  I've thought of doing another amp and trying my skill at doing a Layout, but haven't pursued it--yet!
Title: Re: My first schematic
Post by: shooter on April 27, 2024, 03:32:46 pm
Quote
Did you also create a Layout of your schematic?
take a good finished gut-shot, use colored pencils, lots less brain, lots more fun
Title: Re: My first schematic
Post by: wsscott on April 27, 2024, 03:40:24 pm
Shooter-Could you be a little more "detailed" in your methodology?  (HAHA).