I needed to make a UV EPROM Erasing unit so as to erase the contents of some reprogrammable EPROMs. Nowadays one has the advantage of software / Electrically Erasable versions (EEPROMS)
Visiting the various electrical suppliers in our area was a quite interesting exercise.
Many of the sales people had never heard of an EPROM yet they all were using a desktop computer as located on their desk for processing invoices. The BIOS chip (boot chip) in a desktop computer motherboard is an EPROM !!! so some education information was given by showing them my sample.
I advised my requirements were for a UV lamp of a specific UV frequency and that it needed to be small. I also advised I required the necessary hardware to make it work.
One sales person wished to sell me something that they manufactured for water treatment facilities. It provided 1 kilo-Watt of UV light, was housed in a street lamp housing and I guess had enough power to melt / evaporate anything.
After much searching for a supplier I finally found a company in a neighboring town who were willing to see what I needed, the application that needed to be done and were willing to "loan" me the items. If the items were found to be suitable I could then purchase and EFT the order value. This company was also the only one willing to provide detail on how to connect the hardware. The other suppliers only wished to charge a fee for assembly as "this was a job for an electrician". Little did they know I have worked on X-Ray Spectrometers that have X-Ray voltages of up to 100kV and heavy duty wiring (50 Amp) for many years.
Visiting the various electrical suppliers in our area was a quite interesting exercise.
Many of the sales people had never heard of an EPROM yet they all were using a desktop computer as located on their desk for processing invoices. The BIOS chip (boot chip) in a desktop computer motherboard is an EPROM !!! so some education information was given by showing them my sample.
I advised my requirements were for a UV lamp of a specific UV frequency and that it needed to be small. I also advised I required the necessary hardware to make it work.
One sales person wished to sell me something that they manufactured for water treatment facilities. It provided 1 kilo-Watt of UV light, was housed in a street lamp housing and I guess had enough power to melt / evaporate anything.
After much searching for a supplier I finally found a company in a neighboring town who were willing to see what I needed, the application that needed to be done and were willing to "loan" me the items. If the items were found to be suitable I could then purchase and EFT the order value. This company was also the only one willing to provide detail on how to connect the hardware. The other suppliers only wished to charge a fee for assembly as "this was a job for an electrician". Little did they know I have worked on X-Ray Spectrometers that have X-Ray voltages of up to 100kV and heavy duty wiring (50 Amp) for many years.
Detail is provided below for those interested (click on picture to obtain a larger view)
This visit turned out extremely useful as I now had all the bits and pieces. Even though the offer was to test before purchase, I bought the items. The lamp was used to destroy algae in the water circuit of fish tanks. It was small and met my requirements.
I now needed a housing and was shocked at the prices at various electrical suppliers.
I thus came up with another plan. Purchase a rectangular tin of biscuits at a local supermarket !!! Bit of advertising here for BAKERS our local manufacturer, an example of what was available.
I did a mock layout of the hardware (after removing the biscuits) inside the container and when I was satisfied, mounted and connected all the items as per the provided schematic. I added a safety micro-switch to the electrical circuit so that the power is switched off if the lid was open / opened when switched on. The dangers of UV light exposure needed to be considered. The photo below shows the completed unit.
Please note as the unit is powered from electrical power an earth point was also fitted. Power into the unit is via a grommet fitting. All power connections to / from the micro-switch were soldered and the connections covered with heat shrinkable tubing. Connections to the ballast and lamp holder were of a special design (by the manufacturer). This only required the cable to be pushed into the special "latching" connection. They recommended "solid core" cable.
Confirmation of success was obtained after erasing my first batch of EPROMS and then reading the contents to check they were erased. Each address needed to be a code FF (hexidecimal)
A KISS (Keep It Simple Simon) project that works for me.
This detail was given to the supplier of the hardware as a thank you for his assistance. I guess he will never know when he will get a similar request.
Please note as the unit is powered from electrical power an earth point was also fitted. Power into the unit is via a grommet fitting. All power connections to / from the micro-switch were soldered and the connections covered with heat shrinkable tubing. Connections to the ballast and lamp holder were of a special design (by the manufacturer). This only required the cable to be pushed into the special "latching" connection. They recommended "solid core" cable.
Confirmation of success was obtained after erasing my first batch of EPROMS and then reading the contents to check they were erased. Each address needed to be a code FF (hexidecimal)
A KISS (Keep It Simple Simon) project that works for me.
This detail was given to the supplier of the hardware as a thank you for his assistance. I guess he will never know when he will get a similar request.
Comment: Prior to using the unit please check the insulation of the cabling as used. Check for any sign of cracking / damage possibly due to UV exposure. The electrical suppliers could not provide technical detail if the wire they sold was UV protected !!!