The HP-700LX is a special version of the HP-200LXhandheld computer, with an integrated NOKIA 2110i cellular telephone.

The machine I received from Singapore recently appears to have been well used. Worse yet, at first it wasn't behaving properly. Although it powered up, its display appeared corrupted, and invariably after a few seconds, it lost its mind: froze, went blank, started beeping, or exhibited other forms of erratic behavior.

It is easy to disassemble the lower half of the HP-700LX, which provides access to the main CPU board. Unfortunately, I found no obvious signs of any problems there. One possibility was that it could have been a clock-upgraded machine, but I eventually had to discard that theory as well.

So I decided to disassemble the upper portion. This is much harder, as you must remove the plastic bezel around the display, you must "pop" the plastic hinge cover, and after removing four screws, you must also "pop" the two halves of the display portion apart. I managed to do all this without damaging the plastic or breaking anything. Once I had access to the inside, I was able to thoroughly clean the display, free a stuck component that did not permit the cellular phone to be fully latched, and I also cleaned and reseated pressure contacts that connect the display to a ribbon cable. After reassembly, the display corruption disappeared, and at first, the machine actually seemed to operate normally.

Eventually, however, it froze again. This is when I realized that a mechanical impact (the technical term is a "whack") had a visible effect. So the problem is a bad contact after all! I once again disassembled the machine, reseated ribbon contacts, and looked for other signs of faulty mechanical contacts or bad solder joints. I haven't found anything. Right now, the machine works, but I fear that it may again stop working, either in response to impact, or entirely on its own if the faulty contact misbehaves again.

The integrated cell phone is an early data-capable GSM model from Nokia, the 2110i. Since it is a 900MHz single-band model, I cannot test it on the Rogers AT&T's 1900 MHz North American GSM network. It is also misbehaving when I insert my SIM card. Whether it is because the phone is faulty, SIM-locked, or some other reason, I don't know.

The cellular phone is inserted at the top of the machine. When it is pushed into position, it is latched securely. Since the keypad and display face upward, the phone+PDA combo can in fact be used as a somewhat bulky telephone without having to unlatch the phone first.

When you open the machine with the phone attached, the top half is very heavy, so the machine would tip over, were it not for an extra stub that is attached to the battery compartment door and can be folded out to provide extra stability. Whacky.

Accompanying the cellular phone is a Nokia DTP-2 cellular data card. This card is cleverly hidden inside the HP-700LX, connected to a second PCMCIA slot that is accessible only internally.

The standard suite of ROM-based drivers and applications found in the HP-200LX has been expanded and modified to work with the cellular phone. A good example is the SMS application that lets you retrieve, view, and send SMS messages using the wireless phone.