VK5TM


News, Updates and Other Minutiae

I have, for quite a while, provided modified versions of the code for my projects free of charge. However, the cost of webhosting for this site has tripled in the last couple of years and the little I make out of the pcbs I sell goes nowhere near covering this cost.

As of October 2017, I will be asking for a donation in exchange for providing custom modified code for my projects to help keep this site available.

November 2017

A modification plus software to allow the Simple DDS VFO to be re-calibrated as often as you want without having to re-program the PIC has been added to the Simple DDS VFO page. Simple DDS VFO bug problem fixed. Code uploaded to webpage as version 'c'.

October 2017

There is a bug in the Simple DDS VFO code. See Simple DDS VFO page for the problem and updated code. Included an add-on for the Simple VFO project to indicate which step size has been selected. Simple DDS VFO project updated and software file uploaded. The pushbutton on the encoder is used to change step size (step sizes 10Hz, 1kHz and 10kHz).

September 2017

Noise Canceller kits now available.

July 2017

Updated both the DDS Xtal Substitute and DDS Xtal Substitute Mark 2 projects into one project. The original webpages are available to download as PDF's.

May 2017

New project added - my version of the X-Phase noise canceller. PCB available and a kit of parts to follow soon

Model Railway Electronic Project - Welding simulator - Under construction - Dec 2017

All the Model Railway Electronic Project web pages are a work in progress at the moment, so they may ramble a bit or be a bit disorganised while I refine the various pages. Most of these projects were done quite some years ago without much documentation, so I'm in the process of documenting them, which may take a little while. In the mean time, what I have is being put up here. I designed this project as I was not satisfied with what was available at the time, most welding simulators had one flashing white light and not much else. Today, there appears to be more (albeit expensive) options available, but still none that I could find that simulated the red glow of a hot weld. So what does it do? Well, obviously, it simulates the flashes seen when an arc welder is used by flashing both white and blue LED's. But it also gradually illuminates a red LED to simulate the glowing red area of the weld and when the "welding" finishes, it slowly fades. A couple of other functions I added for the control of this project are: 1: An On/Off control line so it can be controlled by other devices such as DCC modules. 2: Either random periods between when the "welder" activates or the ability to preset a regular delay between activations.

Welding simulator schematic Click pic for a larger image - opens in a new window.

I have designed a 'Universal' pcb that can be used for several different projects (that is why the 'Not fitted' references in the schematic above), but have not yet made one to make sure there are no problems with it. In the meantime, below is a preview of the pcb.

Universal Model Railway project pcb

To do: Expand this webpage with more info. When I can find a HO figure of a welder that doesn't cost an arm and seven legs, make a small diorama and video it to show how it operates. More as I think of it.