Superscan PI

[porkluvr]

I don't care much for the naming convention for the power supplies but I'll give credit to whoever had the patience to trace this from PCB. I know I wouldn't want to have to do it.

[Qiaozhi]

Well. That's just plain crazy, but I know you're right.

It appears that according to arithmetic of the schematic artist, 12V + |-12V| = 12V, or something like that. That's about as clear as mud, but I can live with it.

It would have made more sense to call the supply rails something like Marylou, Dietmar, and Fritz and thereby not defy basic laws of mathematics, but that's just an opinion.

I've seen this before on some other schematics. The "thinking" behind it (if you can call it that ) is that +12V refers to the positive battery terminal (no problem there) and -12V refers to the negative battery terminal. Unfortunately, using normal thinking, this makes it look like a 24V supply is being used.

[ispanyol2]

friends, this scheme absolutely right, there are running friends. and the super-gravity. PBC, but somehow in the hands of someone who did not send the file layout. still waiting.

regards

[mikebg]

I've seen this before on some other schematics. The "thinking" behind it (if you can call it that ) is that +12V refers to the positive battery terminal (no problem there) and -12V refers to the negative battery terminal. Unfortunately, using normal thinking, this makes it look like a 24V supply is being used.

The drawing is custom made for Qiaozhi

[porkluvr]

Goooood job mon. That's smokin'.

[mikebg]

Καλο σου αρεσε ?

Rospy, if your location is Greece, why notes in your sketches of Superscan circuit diagrams are written in Polish? I think the error that I showed in posting # 36 and here below is not made by you but by a Pole or Polish men.

[sinko1]

pcb for superscan?

[Geo]

Strujas, the pcb of Superscan traced by Rospy is single sided. Note that Rospy shows in the above circuits a lot of useless RF chokes. This is not true, the circuit contains no chokes. In reality these components are resistors with zero resistance, ie 0R0. They are used instead wire connections because pcb is single sided.

This schematic of Superscan is from a Bulgarian guy and not by rospy.

[DOOLEY]

hello ,

porklover and mikebg , going back to the +12V -12V thing ,

this way of labling on schematics is very confusing and should be done a better way ,

lots of schematics have this and it's missleading isnt it ,

in this case -12v should be labled 0V to clear up the confusion.

and the whole thing of +5V and -5V , i now know its centered around the top rail , so if top rail is 12V then the +5V is actualy 17V and the -5V is actualy 7V

this whole thing at first was confusing and when viewing new schematics can still be confusing.

a better way would be to use 0V as the referance point , so that 12V IS 12v ,
+5V IS 17V , AND -5V displayed as 7V otherwise people will think its 5V below the 0v rail.

why do people who draw schematics try to confuse / mislead the hell out of us ??

ARRRRGGGGGHHHHHH !!!

MAKE US / ME HAPPY , REFERANCE POINT SHOULD ALWAYS BE ZERO VOLTS , REGARDLESS OF HOW THE BATTERY IS CONNECTED , PLEASE

[mikebg]

Hi DOOLEY
When a schematic has one or more operational amplifiers, the most important rail is noted as COM. At SPICE (simulation), designers note this rail as GROUND. However Robert Podhrasky describes this rail as "intermediate voltage" in an old patent of Garrett.

Despite opamps are not shown on my drawing in post #49, the notation of supply rails is made according SPICE. The drawing shows only TX part of circuit diagram. Note where is connected the COM lead of negative voltage regulator 7912. The symbol GROUND means that the following part of circuit diagram also uses GROUND as COM rail. All voltages are shown relative to COM (ground). Only the battery nominal voltage relates to its terminals.

Most reverse engineers make misleading notation of voltages because they are not familiar with principle of SPICE notation.

[porkluvr]

hello ,

porklover and mikebg , going back to the +12V -12V thing ,
this way of labling on schematics is very confusing and should be done a better way ,
lots of schematics have this and it's missleading isnt it ,
in this case -12v should be labled 0V to clear up the confusion.
<snip>
ARRRRGGGGGHHHHHH !!!

MAKE US / ME HAPPY , REFERANCE POINT SHOULD ALWAYS BE ZERO VOLTS , REGARDLESS OF HOW THE BATTERY IS CONNECTED , PLEASE

One is more than enough and there have been several. They get copied, and distributed without getting corrected.

Hi DOOLEY

Most reverse engineers make misleading notation of voltages because they are not familiar with principle of SPICE notation.

And that's a shame because sometimes that makes it look like the person doing the RE drawing is clueless, but you know they spent a lot of energy on the project!

Annotating power supplies against convention can makes what might be an otherwise viable circuit look like junk. Case in point: Deltapulse. It has a somewhat bizarre but workable power supply arrangement, but the fact that the person doing the drawing indicated +12V and -12V for a single battery, instead of referring one or the other terminal to ground, makes it look like a prank. The math does not add up.

[DOOLEY]

HERE HERE porklover !!

thank you for agreeing with me , i think.

CLARITY IS ALL WE ASK , YES ??

[lucafa]

Hello. Very nice job. Is possible to have the pcb (pdf, eagle) for this project? Many thanks Luca.

[sinko1]

pcb please

[kt315]

I keep this in archive... someone did post it time ago.