While I had the Fluke opened up today, thought I might as well install the upgraded ROMs, not sure why just felt the need to.
The ROMs that are available online for version 3A are doubled up into 3 x 16k files, to be installed I needed to split these files and match them up to the originals.
Here is the .ZIP file with all the split ROMs labelled properly.
The Naomi has a 0.1F super capacitor on board labelled C29, in between the button cell battery and the 8 pin DIP labelled 315-6188. This capacitor is a usual suspect on a broken board as it is prone to leaking and damaging the traces to the serial EEPROM. If you own a Naomi board (not sure if it applies to the Naomi 2) you should check the condition of this cap and replace it.
The capacitors can be ordered from the links below:
CPC
Farnell
Mouser
After reading a simple guide by 1200xl over on the RCM forum, I decided to give this retrobrighting thing a go.
Retrobrighting is a process of removing the yellowing that tends to occur on old plastics. I’ll not go into the science behind it cause i don’t really know it.
As a test subject I used the casing of one of my Fluke 9010a pods.
I ordered some peroxide online and this Saturday was the ideal day to try as to make this work, sunlight is required.
Apply a nice thick coating of the peroxide to the washed down plastic and wrap it in clingfilm, then place it in the sun for a few hours turning it every so often to get all sides.
Probably should mention that rubber gloves are a must for this job as the peroxide doesn’t feel good on bare skin!
After its been roasted, remove the clingfilm and wash off the peroxide and let the plastic dry.
Pleased with the results for a first attempt and have since don’t the body of the Fluke with better results.
I was advised to apply a UV treatment after this as the yellowing will return but at this point I haven’t got any. I’ll get some ordered though.
Will no doubt have more stuff to do in the future.
Got around to dumping the ROMs today for backup purposes.
The version installed is 2B (or 2.1 according to the stickers). I know there is a v3a kicking about somewhere but no one knows what the differences are between them so I wont bother upgrading mine.
The naming scheme for these is taken directly from the ROM stickers.
Also included in this ZIP is the MCU dumps for the keyboard and the tape drive unit.
Fluke 9010a Files
Whilst soak testing the Commando board I had recently repaired for someone 2 bad things happened.
First the music disappeared
Second the pictures vanished.
I checked the RGB outputs with the scope and the signals looked a little weak but should be fine. I checked the SYNC signal and this was stuck HIGH.
Followed the signal back from the edge connector to a 74LS138 IC @ location 5L and the outputs on pins 3 and 4 were both stuck at just under 1v according to the scope.
The inputs to the IC were fine. I piggy backed a working LS138 and the picture came back normal.
The sound fault was fairly simple too.
The first thing I did was check the RESET and HALT lines on the Z80 CPU. These were fine and not stopping operation. Next I checked the clock signals on the Z80 and the Yamaha 2203’s. The Z80 was fine but there was nothing on the 2203’s.
The clock signal for these 2 come from a nearby 74LS74 IC who’s outputs were obviously dead but all the inputs were “as schematic”. I pulled this and testing it, it failed and a replacement has restored the sound fully.
Finally this is in good health once again and hopefully it will stay that way for a while longer, although with the amount of Fujitsu TTL IC’s on the board I very much doubt that but it is 26 years old now!