Software

1. New PC with a UEFI BIOS: I took delivery of a new 64bit Windows 10 based PC and discovered, after the event, that it would not run any version of Windows prior to Windows 10 - some versions of Linux are fine. Since I have valid licences for WindowsXP and Windows7 in order to run some legacy software on a prior PC this was a major inconvenience. The solution was to install a virtualisation package and run the earlier operating systems within virtual machines. There are several such packages available and I chose VMWare - this allows the host PC to share its resources like disk space, USB ports, printers etc with the virtual machine.

The BIOS does not support diskette or floppy drives so file movement must be by memory stick, CD/DVD/BluRay and the network. It has been stated by a number of Linux users that the UEFI BIOS can cause problems with the GRUB boot loader but my version of GRUB from Ubuntu works with no problems. However, the BIOS does allow a nominated drive or memory stick to be booted without changing the boot order which is very helpful.

Several Linux distros were tried but the one that gave the best results was Ubuntu 64 bit. The Nvidia dual monitor graphics card is a relatively new design and finally bespoke Linux drivers did appear.

Windows 11 will run on this PC as it stands but requires a BIOS security facility to be activated. However it is not clear how many of my legacy applications will run on Windows 11.

2. Windows Programs: I write only a small amount of Windows and PIC software these days and will post programmes as they become sufficiently complete to be useable - they will be updated as time allows.

The first one is a simple 32bit engineering workbench containing some basic time saving calculation routines. No installation is required so just download it into a convenient folder and put a short cut to it on your desktop. Please familiarise yourself with how the component value multipliers work - some are case sensitive. There are help forms that explain the operation.

Click here to download the Workshop programme - size is 1.723MB and it has been scanned for viruses with Zone Alarm. Free for use in non-commercial applications. Some formatting error have been corrected and the default number of decimal points set to 2.

The second program is an Excel spreadsheet that analyses the operation of a Vackar tunable oscillator - see here for more information.

Feedback, comments or information on errors is always appreciated to g3oou(at)aol.com

3. Database Thoughts

When designing a database that will feature regular deletions and new additions a useful technique is to create a cache of records that are no longer required i.e. marked as deleted and hidden from the user with an index key that places them above the highest record in the current record set. When a new record is required, the software simply searches the cache for a previously deleted record and changes the index key to make it visible. An overnight process can check the cache size against the database configuration table and make whatever changes are deemed necessary. In one database application I set the cache configuration number to 10% and the overnight processing would ensure that the cache size was at least 10% of the count of valid (non deleted) records.