Introduction: Tachyscope 1.0, POV Led Display

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See my Youtube video Tachyscope 1.0 , NVictria video # 15

https://www.youtube.com/watch?v=4xrWhKwWYcc


This my modern day version of a Tachyscope display machine. My version displays two Serial data channels, one blue leds, the other white. It also has two Nixie numeric displays, one for Temperature / Humidity, the other numeric values for Voltage/ RPM/ Clock/ timers

The video below is an example of Serial data displayed on the POV ( persistence of vision ) display, and "F68" on the nixie is the ambient temperature in Fahrenheit


Also see my first "prototype" of this project here at Instructables

https://www.instructables.com/DUAL-Channel-SERIAL-POV-Display/

Attachments

Supplies

Wood to make cabinet

Brass "facia" from old tube radio

frying pan for Spinner unit

Qty of 5 Arduino's, ATMega 328

Qty of 18 SMT leds for POV displays 1 and 2

Blank PCB material ( copper clad boards) without the copper. to make hand wired "PCB"s

Brass stock flat plate to "etch" front and rear control panels

Brass stock of 2" pipe to make selector switches housing

Brass stock 3/8" thick to make switch plates ( etched)

Colour laser printer to print etching masks

Clothes Iron, (old one) as it will never be used again on clothing, used for laser printer toner transfer to brass

Nail polish remover, also for laser printer mask transfer to brass for etching

Step 1: Making the Main Electronics

There are 3 PCBs in this project, a small 4"x4" located on the Spinner, has 2 ATmega Arduinos to manage display scanning routines, code will be listed in details.

2 large pcbs, approx 5" x 10" to control Serial Data in and Nixie displays

Process to make laser printed PCB graphics.

I use a program called TinyCad to generate a Coloured scaled diagram of the PCB layout, then print it in colour, glue prinout to "PCB" board, ( do I need to clarify) a PCB without the COPPER, once the graphic overlay is glued to board with spray glue, its is drilled with a Dremmel

Step 2: Making Brass Thingys

Here are many photos regarding, printing the graphics, heat transfer to brass, etching, machining on lathe, brass pipe fittings, switch end plated , etched polished installed


Step 3: Schematics

Electronically the project consists of 3 main parts.

Part A = Spinner, this is made up of the circular PCB, and consists of 2 ATmegas, one for each display (white leds, blue leds), labeled POV U1 and POV U2. SEE CODE labeled "POV U2 V1.4 blu" for blue display, and " POV U2 V1.4wht" for white display. see page 2, page 7, page 20

Part B = Large PCB, labeled PCB #2, see page 2, page 5,page 6.2, page 6, PCB #2 controls the NIXIE tubes displays, they include thermometer, voltmeter, RPM meter, digital clock. Has 2 ATmegas U2 and U3, this PCB also has 180VDC psu for NIXIE tubes

Part C = Large PCB, labeded PCB # 1, sw page 2, page 6, page 9, page 10. PCB #1 controls Volt meter inputs, and has 1 ATmega U1, U1 controls baud rate serial, converts port A serial to from 9600 baud to port B serial to from 300N7 baud. PCB #1 has PWM circuit to drive spinner motor speed

Power and data are supplied to spinner via 4 pole slip ring, I send Serial data via opto couplers U13 , U14. This is to minimize noise induced faults.

PT3 aka Photo switch 3 is used to sense RPM rotation.

PT1 and PT2 aka Photo switch 1 and 2 are used to HOME POV displays

Step 4: Software for Arduino ATmega 328P-u

U2_METER_Gen2.5.ino loads onto AtMega U2 see page 5 in schematic PCB # 2

U3_thermometer_Gen2.2.ino loads onto U3 see page 5 PCB # 2

U1_Serial_BLUE_1.5.ino loads on spinner U1, see page 7

U2_Serial_WHITE_1.4.ino loads on spinner U2, see page 7

Baud_v2.5.ino U1 on PCB # 1, see schematic page 9.

Attachments

Step 5: More of My Stuff

Visit my other projects at youtube NVictria, TTY, Cosmac 1802, SPO256 (voice ic)

also at Hackaday https://hackaday.io/project/190143-dual-channel-pov-display