This computer is of a dear friend; Paolo Cognetti.

Short story of the repair:

I have checked the voltages and are correct, although a couple of capacitors on the power stage need to be replaced.

I have tried to turn on the computer and i have see immediately a problem, the screen is full of random characters, with the oscilloscope i have tried to see if i have data stream on the CPU (Z80), interrupts and so on.., nothing, it seemed completely dead, replaced.

The computer has started better then before but with some video glitches, raster lines scrolls from bottom to the top and some characters scattered on the screen. I double checked the voltages and i have realized that the 12v are gone and the 7812 warmed a lot, about 80 degrees after 2 minutes.

Almost all tantalum capacitors of 1uf and 33uF on the 12v line are shorted, i have decided to replace them all (22 pieces)

After the replacement of all tantalum capacitors and two electrolytic capacitors on the power supply stage the computer has started to work correctly but with some video problems, characters scattered on the screen, after replacing two Static RAM 2114 everything works perfectly, including the Basic Cartridge that until now had never worked.

Works that have been made:

• Fixing broken Fuse Holder.
• Fixing a cold welding of a capacitor on the power supply stage.
• Testing Voltages.
• Replaced CPU Z80.
• Replaced 12 x Tantalum Capacitors (1uf)
• Replaced 10 x Tantalum Capacitors (33uf)
• Replaced 1 x Axial Electrolytic Capacitor (470uf)
• Replaced 1 x Axial Electrolytic Capacitor (1500uf)
• Replaced 2 x NMOS 2114 Static Ram.
• Fixed the botton cover with two missing screws.
• Cleaning the top cover using only water and a sponge.

Exidy Sorcerer II Repair Gallery:

Exidy Sorcerer II Gallery:

source: wikipedia

Thanks to my friend Andry for the donation of this DataRecorder.

Laser Slim Line Computer DataRecorder (Model DR-15).

Gallery:

Thanks to my friend Andry for the donation of this computer.

The laser 500 is identical to the previous version, the laser 350. The only differences are in the memory configuration (64 KB instead of 16 KB), the keyboard (77 keys instead of 49) and extended graphics modes.

Technical features:

• Production: 1985
• CPU  NEC D780c (Z80A compatible) at 3.7 MHz
• RAM: 64 KB, expandible to 128 KB
• ROM: 32 KB
• Text modes: 40 x 24 in 16 colors and 80 x 24 in 2 colors.
• Graphic modes: 160 x 96 a 16 col., 160 x 192 a 2 col., 320 x 192 a 2 col., 160 x 192 a 16 col., 320 x 192 a 2 col., 640 x 192 a 2 col.
• Sound: 1 voce, 6 octave (Beeper)
• I/O ports: Tape-recorder (600 bauds), Composite Monitor out, RF Port, Memory expansion port.
• Power supply: 9v 500mA (Positive Centre)

Gallery:

Thanks to my friend Andry for the donation of those two cartridges for Commodore 64/128.

Cartridges:

• KCS Cartridge for C64.
• Captain Miki II (Clone?) for C64.

Gallery:

Thanks to my friend Andry for the donation of a few Software on tape.

Thomson MO5/TO7/TO9:

• Histoire de France (M.P.S.)
• Pays du Monde (Infogrames)

Vtech Laser 310:

• DemostrationsBand (Vtech)

Dragon 32:

• Backgammon (Oasis Software)
• Invader Cube (Oasis Software)

Sharp MZ-700:

• Anthill Raider (Solo Software)
• Flipper 700 (Tecnomec)
• Advoka.
• Head Driver.
• Egg Bas.
• Account Management.
• Address Data.

Timex Sinclair 1000:

• Backgammon.

Radio Shack TRS-80:

• Some tapes of not original software.

Thanks to my friend Andry for the donation of some cartridges for Palladium Color & Bally Astrocade

Palladium Color:

• Game Cassette 606 (Tele-Bowling)
• Game Cassette 610 (Ballspiele)
• Game Cassette 607 (Schiebsport)
• Game Cassette 603 (Autorennen)
• Game Cassette 765 (Motoradrennen)

Bally Astrocade:

• Bally Basic (Astrovision 1981)

Thanks to my friend Andry for donation a few things for Atari

Here the list:

• Modem Supra Corporation 300 AT
• Berliner Cilinder Video Digitizer Atari 520 ST
• Composite Video Switcher (Color/Mono)
• A unknown Interface with 3 x Potentiometers+ 2 x DIN IN/OUT + Cartridge Expansion Port (they have used the cartridge case of the Commodore 64 but the connector is Atari).
• A unknown Harddisk Interface for Atari.
• Two unknown cables with Floppy Drive Connections.

Gallery:

Thanks my friend Andry for the donation of a few cartridge games for the Commodore VIC-20 that i have missed in the years.

Titles:

• Buck Rogers Planet of Zoom (Sega)
• Avenger (VIC-1901)
• Gorf (VIC-1923)
• Saragon II Chess (VIC-1919)
• Mission Impossible (VIC-1916)
• Slot (VIC-1904)
• Alien (VIC-1906)
• Speed Math / Bingo Math (VIC-1933)

Thanks to my friend Andry for donation some games cartridges.

Titles:

Radofin 1292/1392 – Acetronic MPU 1000 – Prinztronic Microprocessor – Audiosonic PP 1292

• Horse Racing (3012 HR) – Boxed
• Prizefight (3014 PF) – Boxed
• Air/Sea Attack (3005 AT) – Boxed
• Shooting Gallery (3006 SG) – Boxed
• Tank/Plane Battle (3004 TP) – Boxed
• Pro Sport 60 (3001 PS) – Boxed
• Circus (3013 CI) – Boxed

Palladium

• Tele-Bowling (Wipeout) – Tele-Cassette 606 – Boxed
• 10 Ball-Spiele – Tele-Cassette 610 – Boxed

Home Arcade – Leonardo GIG – Hanimex HMG2650 – Arcadia 2001

• Breakaway (#17) – Boxed
• Cat Trax (#24) – Boxed
• Grand SlamTennis – Loose

I don’t want to make yet another boring review of the Nintendo Classic Mini, there are many on the net.

I will just say that is made very well, the 30 games included are emulated very well and seem bug free at least i have not found anyone.

The games selection menu is done very well, fast and intuitive.

The appearance is what impressed me, very beautiful and solid.

I have nothing else to say.

Gallery:

source: nintendo

The Commodore Monitor 1960 may have been made by Daewoo (Korea) or a Taiwan company, or may be an OEMed Panasonic Panasync. The tube is made by Hitachi/Panasonic.

There has been some debate over whether it is a true multisync or a trisync monitor. Reports have been provided that indicate it can handle Super72 screen modes at about 23 kHz, and the manual says it can sync up to 38 kHz. It may be a sort of hybrid, with a wide “window” in the 15.75 kHz to 31.5 kHz range.

Gallery:

Download: Commodore 1960 Service Manual (1394)

source: bigbookofamigahardware.com

A nice donation from a friend. Texas Instruments Extensa 460 a laptop of the 90s

Gallery:

Apple Computer 1, also known later as the Apple I, or Apple-1, was released by the Apple Computer Company (now Apple Inc.) in 1976. It was designed and hand-built by Steve Wozniak. Wozniak’s friend Steve Jobs had the idea of selling the computer.

The Apple I was Apple’s first product, and to finance its creation, Jobs sold his only means of transportation, a VW Microbus, and Wozniak sold his HP-65 calculator for $500. It was demonstrated in July 1976 at the Homebrew Computer Club in Palo Alto, California.

—————————————————————————————————————————————————

Apple 1 (Mimeo / Mike Willegal Clone) Assembled for a friend of mine; Paolo Cognetti.

Many thanks for the Technical & Moral support to: Piero Todorovich and Alessandro Polito.
I also thank for some electronic components: Gabriele Molesto Zaverio of Museo Dell’informatica Funzionante, Piero Todorovich.

I had several problems with this Apple 1 clone, i very briefly describe the problems below and i attach some photos of the assembling stages.

• 1 – No video image, all voltages are ok.
• 1 + MPS3704 Transistor failure replaced with a 2N3704 pinout not compatible.

• 2 – Garbage screen during boot.
• 2 + Replaced 2 of 7 Shift Register 2504V

• 3 – Keyboard inputs not working, the WOZ monitor is freezed and shows an “@ \” but the “\” does not wrap.
• 3 + Replaced a 27k resistor half broken, probably during transport the capacitor has crushed the resistor.

• 4 – The keyboard does not respond correctly, typing A they print @, typing 1 they print 0 … and so on …
• 4 + Keyboard adapter from Apple II/+ to Apple 1 in short circuit. A wire is skewered in a pin of a Socket.

• 5 – The computer does not respond correctly, but it seems to work. The WOZ monitor responds to commands but does not write to memory and print random locations.
• 5 + Replaced a 7410 which had a pin always at high level.

• 6 – The keyboard has several problems, some switches are completly dead.
• 6 + Replaced switches.

Photos of the assembling stages:

123►

Video:

The Japanese Commodore 64 was introduced in the 1983.

The Hardware somewhat different (and incompatible) Kernal and BASIC to accomodate Japanese katakana characters, 46 total (plus punctuation, diacritics, etc.); many graphic characters replaced in the Char ROM with the new Japanese characters.

Breadbox case and original brown keycaps; SHIFT-LOCK replaced with C= LOCK for the purpose of getting at the katakana; modified keycaps to show the new characters with the colour keys no longer present and the remaining graphic characters significantly rearranged.

Machine started up in English but different colour scheme and only 36863 bytes free; see screenshot. Both Markus and On the Edge remember the original screen as black on pink, but the screenshot and corresponding ROM definitely aren’t.

Graphics and Sound Identical to the breadbox 64.

Gallery:

Directly from the collection of a dear friend “Andrea Pierdomenico” the Commodore 64 with the wrong key.

The factory was wrong to print the “8″ key but only the upper label and not the front label. I did not find any articles on the net that talks about this keyboard, the only one in the world?

Gallery: