Answers to Frequently Asked Questions

Why is your site slow?

This web site is hosted on my personal DSL connection, as such, downloads over a few hundred kilobytes may take a while.

What is a .ps file?

PostScript, which from the PostScript FAQ, is defined as:

... perhaps the most versatile and loved language for printers, being used in printers world-wide. It is capable of drawing to computer screens and any kind of drawing device. PostScript is interpreted, stack based and has latent typing. It somewhat resembles the computer language FORTH.
A number of programmers write PostScript programs directly for a variety of drawing applications. However, PostScript programs are usually documents meant to be printed that have been generated by a program written in some compiled language.

With that said I'll point you in the direction of Ghostscript and Ghostview/GSview, the utilities you'll need to view these files. (If you don't have a printer which natively understands PostScript you'll need these applications to print as well.)

Why don't you use PDF?

I like PostScript better, but I may use PDF in the future if I manage to get over my intense distrust of Adobe Systems Incorporated.

Why don't you use GIF?

Vector based image formats are generally best for schematics display because they scale well without loss of quality. GIF is a bitmap based image format, hence it doesn't scale well. GIF also has some technical handicaps that limit its effectiveness in high-resolution applications like printing.

Will you convert schematic X from format P to format Q?

No.

Can I link to your web site?

Sure.

Will you join our web ring?

No.

Do you give reciprocal links for the sake of reciprocity?

No.

Will you link my web site from yours?

If you have nothing to do with music electronics, no I won't. Otherwise, mail me the link and I'll check it out.

Where can I find a schematic for ______?

Many manufacturers publish repair manuals so authorized technicians can fix broken equipment in the field. If the device you're interested in is still in production the manufacturer may be willing to help you out or point you in the direction of a technician who can help. Public libraries are also an excellent source of technical information and not to be underestimated; from magazine archives to books on related topics there is usually always something of interest to be found.

Is everything here safe to build?

Mostly, yes. Small signal circuitry is usually pretty innocuous. Amplifiers, power supplies, and anything else that uses high voltage or heavy current could be dangerous if you don't take the required precautions. If you don't know what those precautions are, you should avoid building that stuff until you learn.

What should I do if I find a mistake in a schematic?

Mistakes happen; if you've confirmed there is an error in a schematic send me some mail about it and I'll do what I can to fix it.

Why are the component values used in my device different from those in your schematic?

If you ever trace the circuit in some of your hardware and compare it to the schematic, you'll probably notice manufacturers frequently make slight deviations in component values during production. This is usually just because they want to keep fabrication costs down and the change made economic sense at the time. If the differences are minimal and within allowable tolerances given the nature of the circuit, the deviations are likely of little consequence.

What do component values like 1M2, 4v5, and 4u7 mean?

Using infix units is an international convention I've adopted because it makes a lot of sense. Fractional values simply have their decimal replaced with the unit abbreviation, and whole values continue to use the traditional suffix. For example the above values translate into 1.2 megohms, 4.5 volts, and 4.7 microfarads respectively. This notation also withstands abuse from copy machines much better as decimal points are one of the first things to degrade.

What software do you use for schematics capture, pcb layout, etc.?

I draw all my schematics in xfig. For pcb layout I've been using pcb. Both programs use a plain-text native file format and are open source.

I found "your" schematics elsewhere on the net, what's up with that?

Yeah, redundancy is considered a feature of the Internet, so this is to be expected. It doesn't bother me.