The First Amiga Intro by Lynx/Nightfall.

It only took just under two months to learn from scratch 68k Assembler and Amiga Custom Chip registers.

Well done Lynx!

Download: Retro Love Intro by Lynx/Nightfall (380)

source: pouet.net

First of all, i thank my friend Gerben for giving me the monitor.

This is a Black and White monitor but for some reason a thin transparent film has been applied to the front of the cinescope to simulate the tonality of an amber cathode ray tube, furthermore the APF logo placed on the front of the monitor to the right of the power light is masked.

The TVM-10 APF Monitor is approximately 43 years old and was used with the Computer APF Imagination Machine I/II.

The Monitor had several functioning problems, below is the description of the work that has been done.

• Removing the colored film.
• Replacement of all electrolytic capacitors.
• Replacement of a ceramic capacitor.
• Horizontal synchronism calibration (H-HOLD) by delicately removing the wax that was melted inside the variable inductor.
• Installation of a 1uf polyester capacitor in parallel with the 1.5uf one present for width adjustment horizontal (H-WIDTH) of the image, unfortunately the ferrite core inserted into the variable inductor for manual adjustment is blocked, probably with glue, forcing is not a good idea.
• Check of the Diodes.
• Calibration using the trimmer placed on the front of the PCB of the monitor for the power supply voltage which must be 12v.
• Geometry adjustment.
• General cleaning.

Only one geometry problem remains; the image on the top left side of the CRT tends to bend slightly for about 1cm and the left side of the image is slighty rounded, problem surely attributable to some polyester capacitor or resistance that has lost the capacity/value of the time.

Needless to say i checked almost all the polyester capacitors and resistors in the horizontal section and didn’t find nothing scandalous.

The photo gallery contains all the photos i made during the repair, i take this opportunity to thank a user of the plcforum who gave me tips on how to proceed with the repair.

Gallery of the repair:

123►

Apple ][ EuroPlus Repair.

Defects:

• Black screen.
• Power light off.
• Keyboard does not work.

Repair:

About the black screen it was enough to press all the IC in their seat, i have removed some and cleaned the IC's socket and the IC's pins.

The Power light off, the 5v micro bulb was faulty, replaced.

The keyboard had several problems;

The keyboard connector (socket) located on the computer motherboard side was faulty and consequently are missing the -12v for the keyboard encoder PCB.

The 3 TTL chips had been replaced on the keyboard encoder PCB but 2 x 74LS04 are erroneously soldered instead of 2 x 74LS00, the third TTL was correct but not working. Replaced all.

Now everything works reasonably well, unfortunately the bad keyboard has some problems, the internal slats are warped and tend out of their seat, as a result some keys do not work correctly.

I have tried to fix and clean, but the situation hasn't improved much.

Gallery of the repair:

After the usual boring PSU recap i have decided to add two displays to monitoring the main voltages (+5,+12) and the amperage.

The amperage displayed with the blue LEDs in the left display is the sum of all the voltages (+5,+12,-12).

I have also added three ventilation holes, i didn’t want to use any fans, i already have enough fans in the lab that are quite annoying.

Gallery:

Texas Instruments PHA 2037 Connector FIX

Defect:

• Black Screen but sounds works.

Replaced parts:

• 1 x 6 PIN DIN Male.

Gallery:

Texas Instruments TI-99/4A Repair #1

Defect:

• Black Screen and deafening sound in background.

Replaced parts:

• 1 x TMS9900NL CPU (U600)

Texas Instruments TI-99/4A Repair #2

Defect:

• Wave/Raster Lines.
• Garbage on Boot Screen.

Replaced parts:

• 1 x Inductor 2 -> 4.5 μH (L100)
• 2 x TMS4116-15 RAM

Texas Instruments TI-99/4A Repair #3

Defect:

• Garbage on Boot Screen.

Replaced parts:

• 1 x MOSTEK MK4116N RAM

Video amplifier installation for Composite Video output including installation of the two female RCAs on the case.

I also made a simple fix of the metal PAD of the RESET that no longer stayed in place and consequently fell off inside the shell.

Gallery:

You shouldn’t turn on an Amiga that has been off for about thirty years without first running the usual Recap, but also following this simple rule it is not said that everything works as expected.

After the Recap i have realized that the RGB / Composite and RF output were not working properly.

From the RGB output the BLUE color was missing while the composite video and consequently RF show only a black screen.

After various measurements i came to the conclusion that the VP-101 (U30) DAC had to be replaced.

Once the DAC was replaced, the RGB output started working perfectly again, while the Composite/RF video signal they still didn’t work.

The failed component for the Composite/RF video output is the Z222 delay line, bypassing the delay line on the pins of the same one i have a “decent” composite signal but it’s not good, unfortunately this component is not easy to find, it could be solved by performing a “hack” i.e. by installing a different RGB Encoder that doesn’t need the delay lines and with some modifications on the PCB.

The game is worth the candle ? when will we use the Composite/RF video output ? probably never.

Gallery of the repair:

Commodore 64 (ASSY 250466) Repair

Defect:

• Black Screen and then Black Screen :-D

Replaced parts:

• 1 x Power Switch
• 1 x PLA 906114 (U17)

Commodore 64 (ASSY 250407) Repair

Defect:

• Garbled Screen and then No Sound.

Replaced parts:

• 2 x MOS 7708 [74LS257] (U13/U25)
• 1 x MOS 7709 [74LS258] (U14)
• 1 x MOS 6581 (U18)

Commodore 64C (ASSY 250469 REV-A) Repair

Defect:

• Garbled Screen.

Replaced parts:

• 1 x 4066 (U21)

The return of the Hybrid Sid Player by xAD/Nightfall & Gianluca Renzi (RetroBit Lab)

Based on the Project and Hardware Schematic by Markus Gritsch released in the years 2011-2015 on the forum dangerousprototypes. Thanks Markus.

Changelog:

v1.22 – 6/2/2023

Note:

• From this release the new versions will be developed and tested on the v2 prototype PCB and no longer on the Breadboard prototype.

Added:

• Software implementation of the new audio Switcher.
• Added a new value (0: Nothing) to the DEFAULT_SID_SOCKET in the configuration file (config.ini).

  # Choose the default SID Socket on bootup (0: Nothing – 1:Socket #1 – 2:Socket #2) – default: 1
  DEFAULT_SID_SOCKET=1

• Added control via MCU of the power-up led. It might come in handy for future implementations.

Updated:

• Updated label on the oled display for the “sid switch” mode, now “sidSet” is written and not just “sid”
• Updated boot screen with the text “sorting files…” if the folder contains too many files (max 800).

Fixed:

• The encoder cannot be used for manual SID SWITCH mode in case the SID tune played is multitunes because the encoder is used to select the songs, so although the “sidset” option will be displayed on the display in this  specific case the selection of the sid socket will not working.
• Logic for the switch of the Socket SID with which to play the song and the consequent LED.
• Default SID Socket if nothing is specified in the config file (config.ini)
• Manual “sid switch” mode, the SID that was played with this mode would stop after 2 minutes and start over.

The return of the Hybrid Sid Player by xAD/Nightfall & Gianluca Renzi (RetroBit Lab)

Based on the Project and Hardware Schematic by Markus Gritsch released in the years 2011-2015 on the forum dangerousprototypes. Thanks Markus.

Changelog:

v1.21 – 29/9/2022

Added:

• A new MODE has been added and can be used with the MODE key while you are in TUNEINFO screen.

This mode allows to change the SID model in realtime while the music is playing.

Example:

If a SID music is played with the SID 8580 positioned on SOCKET #1 by choosing the ‘sid’ mode you can with the encoder turning it to the Right or Left choose the SOCKET #2 where for example where is installed a SID 6581. The led placed under the Socket will show the sid you have chosen.
 
An apparently useless option which, however, can be used to experiment the differences in reproduction of the piece of music with two different SID models or choose the most appropriate sid model if the SID not specified the SID to be used.
 
So in summary we have these choice with the mode key while you are in TUNEINFO screen.

- Single Play
- Sequential Play
- Random Play
- Intro Play
- Sid Switch

Updated:

• Source code description.

Fixed:

• Missing the default value of the startSong in the SID Header if this value is missing. The SidPlayer sets 255 and try to play it.

I only found one SID with this strange configuration : Hammer Down by Sean Connoly.  Fixed by setting it to the default value : 1.

• The player freezes while browsing file system folders with many *.sid files.

This happens when the driver scan the file system and immediately after is done the bubble sort routine that takes about 700ms for 512 entries and more for the max entries (800) in one single directory and during this time the sid player freezes.
 
To avoid hearing the annoying last note played repeatedly for this amount of time, i have forced the player to pause and remove it as soon as the contents of the new directory will be displayed.
 
Obviously if you had chosen to pause the song voluntarily with the appropriate button, it will not resume playing after the new directory is displayed.

The return of the Hybrid Sid Player by xAD/Nightfall & Gianluca Renzi (RetroBit Lab)

Based on the Project and Hardware Schematic by Markus Gritsch released in the years 2011-2015 on the forum dangerousprototypes. Thanks Markus.

Changelog:

v1.20 – 30/7/2022

Added:

• Combo buttons to go up of one directory.

The new feature working when you are in FILE BROWSING display mode and by holding down the button MODE and at the same time press the button of the ENCODER you can go up of one directory.

This mode is very useful if you have a list of many files or directory and would like to easily go up of one directory, currently you should scroll at the beginning or at the end of the list and then click on the double dot to go back, really boring.

Updated:

• Modified the way for the horizontal scroll of the sid filenames list.

I was not very convinced by the system that i have made for scroll the filenames horizontally, so i changed the mode, in my opinion much nicer.

By holding down the MODE key when you are in FILE BROWSING display mode you can move the entire screen with the filenames list left and right using the same encoder that is used to scroll the filenames list up and down.

Moreover the horizontal screen position is maintained also after the switching of the display mode or if you go up of one or more directory.

The return of the Hybrid Sid Player by xAD/Nightfall & Gianluca Renzi (RetroBit Lab)

Based on the Project and Hardware Schematic by Markus Gritsch released in the years 2011-2015 on the forum dangerousprototypes. Thanks Markus.

Changelog:

v1.19 – 22/5/2022

Added:

• Added the horizontal scroll of the sid filenames list.
  • The maximum allowed length of the sid file including extension is 48 characters, the small oled can display a maximum of 20 characters, so this feature is useful with very long file names. The function is activated with the MODE key when you are in browsing files mode, once the 48 characters are reached, the scroll resets and repositions the display of the file from the beginning until the next pressing of the MODE key.

Updated:

• Added a new parameter to the configuration file (config.ini).
  • Choose the default SID Socket on bootup. This configuration is not mandatory.

Below is an excerpt from the “config.ini” file.

# Choose the default SID Socket on bootup (1:Socket #1 – 2:Socket #2) – default: 1
DEFAULT_SID_SOCKET=1

Fixed:

• Wrong emulation for the NOP opcode. %-)
  • I noticed this problem with a SID made by Hermit of Samar Productions, SIDRIP Alliance, Singular that uses a SID Player written by him. SID Tune: MSK Cover-XF End (https://csdb.dk/release/?id=214247)  This SID Player uses several illegal opcodes and i immediately thought of an emulation problem of these illegal opcodes, instead it was the NOP opcode that had problems. I point out that i listen at random 7XX favorite songs at least 1 hour a day and i never noticed any problems. :-D  Anyway, Fixed.
• Max entries per directory.

The PCB of our SID Player rev v2.0 is finally here.

Missing only the assembly and testing.

Gallery:

Note:

The return of the Hybrid Sid Player by xAD/Nightfall & Gianluca Renzi (RetroBit Lab).

Based on the Project and Hardware Schematic by Markus Gritsch released in the years 2011-2015 on the forum dangerousprototypes. Thanks Markus.

This Amiga 1200 was sent to me by a friend to made the usual replacement of the capacitors and also overhaul everything and migrate the pcb to a new case with a new colored keyboard.

Works that have been done:

• Replacement of all electrolytic capacitors.
• Cleaning the expansion connector which was oxidized in some parts.
• General cleaning of the PCB.
• Kickstart OS3.2 installation
• Replacement electrolytic capacitor in the Panasonic JU-253-043P Floppy Drive
• Floppy Drive Cleaning.
• Greasing of Floppy Drive mechanical parts with silicone grease.
• Painting of the Floppy Disk eject button with matt Black color (Only the black button for Chinon Floppy Drive is supplied with the new case)
• CF Card adapter fixing.
• Installazione PCB and colored keyboard in the new case.
• Functioning test with Floppy Disk and CF Card.

Gallery:

12►