This cheap and easy to use add-on speeds up the 1541 Commodore disk drive. Barry Miles gave it a whirl.

The slow speed of the Commodore disk drive has been an irritation to the users of the Vic and Commodore 64 ever since it came out. But now this has been remedied by a nifty device called the Express Cartridge produced by Ram Electronics.

As its name suggests, the essence of the Express Cartridge is that it doubles the speed at which the data is transferred to and from the disk drive. It comes in the form of a cartridge with two wires protruding from it. After slotting the cartridge in, these must be attached to some pins inside the machine.

Setting the system up is not simple, especially if you are of a ham-fisted disposition. The C64 must be taken apart and the 6501 and the chip in the V14 socket located. The two hooks on the ends of the wires are then clipped onto pin 28 and pin 15 respectively. After reassembling the machine, you are ready to go.

The technique is not difficult, but it may deter someone who is not used to handling electronic components. The clip-on approach as opposed to soldering, however, has the advantage that the machine can be returned to its original state with just a few scratches on the screws.

All that now remains to do is simply to insert the cartridge into the slot. Some care is necessary as the attached wires are rather short and can easily be pulled free of the pins. If this happens, the C64 must be taken apart and the wires reconnected.

People using motherboards may find installation a little easier because, when the cartridge stands upright, it places less tension on the wires, Ram Electronics tells me that the wires are longer on current models.

On power up, the ability to work at a much higher speed is immediately available. The Express can be toggled on and off using the F1 and F3 function keys. F1 is on, F3 is off. An additional feature of the system is that RUN/STOP now produces a LOAD and RUN from the disk instead of the cassette.

This facility, which also exists on the SX 64, is a big advantage for the loading of Basic programs. However, if your program is in machine code and needs to be relocated to run, you will find that you have to go through the normal ritual of LOAD "program name", 8,1 in order to get the machine code relocated.

When loading, the Express gives a speed advantage of about three times over other normal systems and, considering the normal speed of the 1541 disk drive, this is quite an improvement.

The Express is completely transparent to most software except for some programs that will not work since they use the bus in an unusual way. In this case, the software needs to be loaded in slow mode. The other problem that may occur is that not more than one device maybe connected to the C64 when using 'fast' mode. This does not apply when using two disk drives, and in this case adjustments need to be made to the Express to get things going. This involves turning one of the disk drives off, allowing fast mode to be used with the other. If two drives need to be used at once, the cartridge becomes redundant and only slow mode can be used. This will probably not be a problem for most people as a lot of C64 software is written with only one drive in mind.

The one remaining question is, how is it done? Ram Electronics is extremely reticent about this and all a reviewer can do is to guess. There are a number of ways that it could be done: one is increasing the read and clock speed of the DOS; another is to use two data lines instead of one. There is bound to be a fairly simple solution since things that work well are generally easy to do - but Ram is not about to let on.

This is a very convenient piece of equipment calling on the user to make the bare minimum of alterations to achieve a significant speed increase. It is a far cheaper alternative than buying a faster disk drive and the appropriate interface to run it, and it should therefore appeal to many users.

One possibility well worth considering is cutting the wires and inserting a connector so that the Express can be attached and re-attached conveniently. In fact, the wires are only necessary when certain types of zero page operations are carried out by a program.

Ram Electronics had this type of connection fitted to the samples demonstrated at the Commodore User Show, and it would have been nice to see it on a production version. Aside from this, it is a very worthwhile piece of equipment.