Scanner/Color/ Test board

[mixedgas]

good quality test patterns add 34$ in parts and 20$ in boardspace per unit. plus i have to sell 20 of them to justify the extra board costs,
and by the time you look at my time to hand enter 1380 data points into a microcode, the time value of money goes through the roof.

basic engineering economics says, conventional patterns are not applicable in this price range, save the additional 54$ for other things.


This is targeted at the entry/mid level user who cannot find a oscilloscope in Yorkshire, or Suffield, Alberta, or West Lodi, Ohio. Its also targeted at FB3/soundcard users who need diagnostics.

Or users who just got a new laser and can't bias it on.

A STFU uses chips that can be found anywhere in the western world and most of the third world. No microcontrollers, all opamps and HC-TTL.


It shall be called "System Test Fiducial Unit". STFU is not a accidental choice of acronym, and only SPEC could get me to change that.
Besides, The Laserists Friend" sounds wussy, and "Test Set four A" was already used by both the US Military and the Phone company.

The idea is based on a widget the telco uses for the now outdated copper pairs.

The main goal of this is to provide a quick system test. Is my (insert software package here) messing up or am I miswired?. Idea is buy or borrow a STFU, follow a series of steps. Then put the video on youtube, and PLers can tell you whats up from the video. It .has to fit on a 3"x3"(7.6 x 7.6 cm) board to get the low costs. The biggest costs are actually the circuit board and db25 connectors and switches and labor.

A STFU, a voltmeter, and some scrap wire lets you do basic checks on cables, scan heads, lasers, and interlocks and dacs , and the voltmeter is optional.

A stfu can be calibrated from scratch with a unmodded sound card, a sniff of 50 or 60 hz from the power line, and a decent voltmeter. However I doubt you'd ever need to change the "factory" calibration.

Steve

[allthatwhichis]

Thank you Steve; second time in my life I have seen or heard "Fiducial", or its derivative, used. The first time was while I was on Jury duty...

[Doc]

Hows about the new Steve Roberts PALMS tester? (Portable Analogue Linearity, Modulation & Scan tester), it's like a test bench in the palm of your hand.

"Buy it now, or we'll send the boys round"

Seriously though; it could be a stress saver as a quick check, when you're in a noisy club, you've got no green, or no Y axis and the promoter is stood over you, trying to help you fault trace, by repeatedly looking at his watch and telling you that DJ Megastar is on in 2 minutes.

Ian

[mikkojay]

Sign me up- It sounds like a very handy device indeed.

[Pitts]

Put me down sounds like a good idea..
Ray
NZ

[buffo]

I'm in for one...

Adam

[Stuka]

Me too - provided a users manual is included for us more technically challenged folks....

[Things]

A STFU uses chips that can be found anywhere in the western world and most of the third world. No microcontrollers, all opamps and HC-TTL.


It shall be called "System Test Fiducial Unit". STFU is not a accidental choice of acronym, and only SPEC could get me to change that.
Besides, The Laserists Friend" sounds wussy, and "Test Set four A" was already used by both the US Military and the Phone company.

The idea is based on a widget the telco uses for the now outdated copper pairs.

The main goal of this is to provide a quick system test. Is my (insert software package here) messing up or am I miswired?. Idea is buy or borrow a STFU, follow a series of steps. Then put the video on youtube, and PLers can tell you whats up from the video. It .has to fit on a 3"x3"(7.6 x 7.6 cm) board to get the low costs. The biggest costs are actually the circuit board and db25 connectors and switches and labor.

A STFU, a voltmeter, and some scrap wire lets you do basic checks on cables, scan heads, lasers, and interlocks and dacs , and the voltmeter is optional.

A stfu can be calibrated from scratch with a unmodded sound card, a sniff of 50 or 60 hz from the power line, and a decent voltmeter. However I doubt you'd ever need to change the "factory" calibration.

Steve

"Hold on, let me get my STFU" "Let you get your shut the f*** up?!?!"



I may be interested.

[allthatwhichis]

I wonder if there will be a complaints department... or I can guess the standard reply...

[mixedgas]

I wonder if there will be a complaints department... or I can guess the standard reply...

The acronym was choosen because how many times have we seen:

"My (insert name of vendor here) board only puts out 4.3 volts and it was messing up Kung Fu on the neighbors TV last night...."


But with a PALMS/STFU we can say, here, buy this board, it uses your own galvos as a readout and is nearly infallable, and you can't argue with it.
----------------------------------
One of the things I'm doing in the stfu design is sourcing a 5V reference voltage. You hook the STFU ramp to your X scanner, you hook the 5V ref to the STFUs Y axis differential driver input using a jumper. (jumpers are much more cost effective then switches) You mark on the wall with a pencil where 5V is, because now there is a horizontal line 5 V up. Next you hook the STFUs Y axis to a ground. Now you mark your zero line on the wall.
STFU has a potentiometer on it for 0-5V. SO with a voltmeter now you can put lines at whatever voltage you want.

You now move the jumper to the R,G, or B output signal from on the hardware to be tested, and you see the actual blanking levels in real time, ie its a laser oscilloscope. A voltmeter hooked to a terminal strip on the side also now gives you a integrated reading of the signal voltage.

I'm not saying some folks are totally wrong, but most of the time the hardware from most vendors works out of the box.

STFU outputs a 0-5V ramp that is synchronous with the X axis ramp. You can patch that signal to your laser if it has a analog input. Now you see your color linearity.

STFU outputs a 0-5 v signal that is a rectangular pulse, centered in the middle of the ramp. Now you can get a rough idea of your rise and fall times at look at jellybeaning. This signal is limited and will also drive TTL.

PALMS/STFU will output a quad square and quite possibly a circle. 3 trimmers on the board will let you supply R,G, and B static levels. A pushbutton will be provided for those who need to quickly test their blanking.

A counter chip rigged as a long divider will let you cycle through 7 colors plus black synced to the quad square. Good quality FET gate Driver chips will supply sharp rise time 0-5V waveforms.

This is all really simple circuitry, but used in a clever way. And it comes with 2 diff to single ended and 2 single ended to diff converters. So you can diagnose a problem quickly by using jumpers as patch cords. A "flip book" of patch settings supplied as a PDF makes it easy to do tests.

I will try to lay it out so that if you want to add your own switches, it will be easy to do so.


See where I'm going with this? I've built all the different parts of this before, I just need to combine them into 1 board.


PALMS STFU will have DB25 input and output connectors.

BTW, this is not my original idea. Fred Fenning (Image Engineering, Inc) provided a card with a 8 bit counter driving a dac chip to provide a standard "Ramp with Pedestal" for tuning his card cage systems, because galvo blanking was hard to standardize. I have one. I'm adding a few features to the idea, mainly the scope mode and the pattern generation and averaging measurment.

Steve