80C552 board

Hello

New toy – a Philips PCB80C552-5-16WP based single board computer.

The board is designed to have 64KBytes of EEPROM from 0×0000 to 0xFFFF, 32KB of SRAM from 0×0000 to 0x7FFF and 32KB of peripherals space from 0×8000 to 0xFFFF

On the same board I’ve placed a SPI RTC, EEPROM and 4.096 voltage reference for the on-chip ADC.

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Category: Electronica, Proiecte

New toy

Just got a new toy, to start working on some interesting projects: an HP3466A almost my age, but still kicking

Here are some pictures:

Related Images:

Category: Electronica | Tags:

Chinese PSU fix

Hello

This is a quick teardown and fix of a Chinese variable power supply.
While trying to measure a negative power supply I’ve discovered that the negative terminal was shorted to main’s earth and case

00__mg_4342

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Category: Electronica | Tags: , , ,

Notebook restoration

Hello.

In this post i’ll show a quick walk-trough on how I managed to re-use an old Asus A6RP that had a sad ending.
In a few words, the entire case got smashed to plastic splinters. Luckily the internal components survived.
The case was rebuilt around two 4mm transparent acrylic sheets and 2.5mm pcb stand-offs, 10 and 15mm tall.

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Category: Electronica | Tags: , ,

RGB led lighting module update

top layer

Hello
This is an update for the led lighting project.
The design in complete and the PCB’s are almost ready.
This is the schematic:

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RGB led lighting module

Hello

I’ve started a new project: a RGB led lighting module, that can be controlled from a central communication node.

I’ll be using some SMD rgb leds, in 5050 case, that i ¬†got from e-bay.

The Imax is specified to 40mA, but i’ll be running them at 30mA max, to keep the heat down.

The design features are :

  • 50x50mm per module
  • cheap controller, JTAG interface, enough cpu power for high resolution/ speed PWM
  • the ability to run stand-alone, following a pre-programmed sequence
  • RS485 line drivers
  • wide input voltage range

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Ceas cu afisaj VFD

Ca o prima postare am ales un proiect mai “aratos”: un ceas cu afisaj VFD

Pentru afisaj am folosit un tub IV-18:

IV-18 tube

IV-18 tube

Caracteristicile tubului sunt:

  • 9 digiti, 8 cu 7 segmente si virgula, 1 cu simboluri speciale.
  • tensiune de filament : 5V la 85mA
  • tensiune anodica: 20-30V
  • curent de grila: 11mA per digit
  • curent anodic: 8mA per digit, cu toti anozii aprinsi

Mai multe informatii puteti gasi aici
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Category: Proiecte | Tags: , , ,