ZXnet

Total Peripherals TP386SX20

A fairly normal PC built by Total Peripherals (now an Australian ISP) on 4/2/1992. It's powered by a 16MHz 386SX processor, not a 20MHz chip like its model name might imply. Perhaps a previous owner (Hort+Research or DSIR) replaced the motherboard at some point, or maybe its always been an SX-16.

Specifications

The configuration of this machine is unchanged from how I received in around 2002 except for the 50MB hard drive — I don't remember if that was removed by me or the previous owner.

This machine currently has no allocated task so it lives in storage. It was pulled from storage in April 2024, dismantled, cleaned, drives lubricated, and tested. In March 2024 it was given a new battery and inventoried as COMP-0010.

The current battery consists of 3x AA-size LiFeS2 cells with a 1N4148 diode to protect them from being charged by the motherboard. The motherboard contains two diodes with a combined voltage drop of 0.527V between the battery connector and the RTC chip. Combined with the 1N4148 built in to the battery pack, the voltage seen at the RTC chip is 1.1V lower than measured at the battery.

Performance

This is not a fast machine. A 386SX-16 that can't be upgraded, no cache, and no ability to install cache. The third screenshot below (click to embiggen) shows that with turbo turned off it runs at around 10MHz.

Current Issues

This machine has the following issues waiting to be resolved:

• It needs a sound card
• It needs a hard disk
• The battery pack needs to be fixed in place somehow (probably velcro)

Inventory Data

This is a subset of the hardware inventory record for this computer. It may be more up-to-date than the rest of this page.

Built 4/2/1992. Acquired sometime around 2002 from Hort+Research. Machine is original aside from the 50MB hard disk which was removed at some point. 
Despite the model name, the CPU is only an SX-16 - perhaps Hort+Research or DSIR replaced the motherboard at some point.
Retrieved from storage, cleaned and tested 21-APR-2024. 
Constructed a new 3xAA battery holder with 1N4148 diode to prevent charging 08-MAY-2024. 
Battery is currently floating and should be checked before powerup after moving - needs to be velcro'd in place