Author: Graham

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BSides Adelaide May 2025

Posted on by Graham

A couple of my colleagues, Mike and Craig, and i represented the Adelaide Retro Computing Group at the BSides event in May 2025.

They gave us half of a very large room at the Adelaide Hilton. Between us, we had about 15 retro/vintage machines for the cybersecurity community to experience.

The scene below is how things looked just prior to the start of the second day.

Data Recovery

Posted on by Graham

I have become familiar with tools for recovering files from floppy disks. I’m happy to help people recover important files from the past.

If you have files on 1.44MB 3.5″ floppy disks then just buy a USB drive, plug it into your PC, and copy the files.

If you are in Adelaide or thereabouts, and you have 720k 3.5″ disks, 5.25″ disks or 8″ disks that contain some important files, and you have had no joy with professional recovery services, then contact me and i’ll try my best to help.

Also, contact me if you have 5.25″ or 8″ disks that need a new home!

Buying & Selling etc

Posted on by Graham

I regularly buy and sell machines and peripherals. This is not a profit making activity for me; it’s just an important part of managing my hobby.

The temptation is to acquire an ever greater number of machines, but i only have so much space. I now sell/give as much as i buy/acquire. It’s not a profit making venture. I try to recover my costs, but that’s not always possible. In this hobby we have to accept that sometimes we pay for the entertainment value of constructing, restoring or embellishing a machine.

I will post items that are for sale on this site, but i would rather sell low than go through the hassle of postage. Typically, i prefer pickup either at my shed (Cockatoo Valley SA) or at a monthly ARC meet (Unley SA).

Repairs

Posted on by Graham

I often buy machines that need repairs because they are much cheaper and i get a kick out of fixing them.

I have benefited from a lot of support from ARC members. I try to pay those debts back/forward by doing repairs for other people. There are many in the vintage/retro community who do this. Andrew P and Daniel immediately come to mind.

This sometimes gives me the bonus of working on machines that i don’t own and has included a Lisa, A2000, X68000, 128D, Computer phone, ECS 4500, Microbee etc.

If i agree to do the job there is no labour cost, no warranty and no time limit! There’s no harm in asking, particularly if you have something interesting. No recaps though; i loathe them.

Using HD 5.25″ FDDs as 8″ Drive Substitutes

Posted on by Graham

High density 5.25″ disks have much the same capacity as 8″ double density disks, and they operate at the same data rate. A 5.25″ FDD typically has a few more tracks than an 8″ FDD.

This means that a floppy disk controller expecting to see an 8″ disk drive can potentially be fooled into working with an HD 5.25″ drive. This can be very handy if you don’t have an 8″ drive or if you want a more compact setup. This trick seems to work ok with a real HD drive or with a gotek/flashfloppy. 8″ disk images can be written to HD 5.25″ media without alteration using Greaseweazle, for example.

There are a few small issues. The first is the 8″ drive interface is usually 50 pins and the 5.25″ interface is usually 34 pins. The disk controller may have both interfaces (eg the Jade DD and the 16FDC) but not always (eg the Pulsar Little Big Board only has a 50 pin interface). If there is no 34 pin interface, then an adapter will be required. The 50 pin interfaces vary a bit, so a specific adapter may be required.

The second is that 8″ drives can detect whether a drive is single or double-sided and tell the host. The operating system driver may exploit this information (eg Jade DD CP/M) so there may need to be a way to fake this. For systems that use only single sided or only double-sided disks the signal can be tied appropriately otherwise a switch may be required – and if there are different drives in the system then it may be necessary to take the signal low through a diode from the drive select line.

Third is that 8″ drives typically produced a ready (RDY) signal. Without this signal, a host may just hang. This signal is available on many drives and can usually be setup on a gotek/flashfloppy but it may not be connected on the 34 pin interface. This can be overcome by connecting pin 34 on the 34 pin interface to the appropriate pin on the 50 pin interface.

Commodore 64C Family Pack $340

Posted on by Graham

This was a gifted by a Rotarian. Sale proceeds will go to the Rotary Foundation.

Commodore 64C – Nice cosmetic condition.  A little yellow on the rear panel and backs of keys.  Loads up games.  Sounded and looked good with my monitor and cable. No manual

Diagnostic cart identified faults with 6526 U2 6581 U17 and Control Port.  Sound test sounded fine. Joystick test program showed ports, joysticks, and paddles working fine.  I have not noticed any issues in use. 

Power Supply – works. 

1541 Disk Drive – passes Commodore performance test and loads games.  A few small cable “melts” on the case. Includes box, cable, and manual.

Datasette – it would detect titles but would not start loading.   Includes box and manual.

Accessories, games, and boxes including:

  • 2x Joystick – One with a homemade replacement cable.
  • Paddle set
  • Cartridges: Le Mans, International Football (both worked for me)
  • Tapes: Armchair Cricket, America’s Cup, SWAT, Desert Hawke (I only got SWAT to load)

RF Cable but no other video cables

Does not include monitor.