11-08-2012, 06:52 PM
Well, not so much 'homebrew' in the sense that I designed it, but I did build it from a magazine design.
This is a function generator I built from Everyday Practical Electronics mag about 10 or so years ago. For many years, simple function generators producing sine, triangle and square waves up to a frequency of about 1 MHz could be built using the wonderful cheap and then widely available 8038 IC, and I did build such an instrument, which I still have. Then the MAX038 IC came along, extending the frequency range to 10 MHz or a little more. Like the 8038, the MAX038 was a complex IC which enabled a function generator to be built with few additional components.
The generator was built on two PCBs which I etched from the magazine artwork. One PCB has the front panel controls, IC and other components mounted upon it, the other PCB had +/- voltage regulators to provide the voltages required. Apart from that, and the mains transformer, there wasn’t much else to it. I housed it in a project box by Vero, and made the front panel by using Letraset rub down transfers on a piece of white card, mounted behind thin acrylic sheet. I hate to admit it, but despite wonderful software being available nowadays to create professional looking from panels, dials and the like, I’m afraid that my CAD skills remain slim to non-existent, so if I had to make another front panel, I would most likely have to resort to Letraset. I am not worthy!
My constructional skills, such as they are, have always exceeded my technical skills and over the years I’ve made many projects that didn’t work, not knowing if I’d made an error or there was an error in the publication. Often it was the latter, with corrections published months later. Luckily, this was one of those projects that worked right away, and still does on the rare occasions that I use it.
I’ve taken a few screen shots on the ‘scope, one of which - if you look carefully at the dial on the generator - you’ll see is set to a sine wave of 10 MHz. The other shots show square and triangle waves. As is the way of the world, the MAX038 IC has sadly gone to same way as the 8038 – obsolete. Almost all projects these days - particularly in EPE mag (mostly sourced from ‘Silicon Chip’ mag ‘down under’ in Oz), seem to be PIC based – another skill I’ve not got into. Like the ICs, my skill-set is becoming obsolete, but I bimble along, muddling through quite contented as the world passes me by!
Hope it's of interest.
Quote of the day:
'Use what talents you possess - the woods would be very silent if the only birds that sang there were those that sang the best'.
Henry Van Dyke.
He was clever!
This is a function generator I built from Everyday Practical Electronics mag about 10 or so years ago. For many years, simple function generators producing sine, triangle and square waves up to a frequency of about 1 MHz could be built using the wonderful cheap and then widely available 8038 IC, and I did build such an instrument, which I still have. Then the MAX038 IC came along, extending the frequency range to 10 MHz or a little more. Like the 8038, the MAX038 was a complex IC which enabled a function generator to be built with few additional components.
The generator was built on two PCBs which I etched from the magazine artwork. One PCB has the front panel controls, IC and other components mounted upon it, the other PCB had +/- voltage regulators to provide the voltages required. Apart from that, and the mains transformer, there wasn’t much else to it. I housed it in a project box by Vero, and made the front panel by using Letraset rub down transfers on a piece of white card, mounted behind thin acrylic sheet. I hate to admit it, but despite wonderful software being available nowadays to create professional looking from panels, dials and the like, I’m afraid that my CAD skills remain slim to non-existent, so if I had to make another front panel, I would most likely have to resort to Letraset. I am not worthy!
My constructional skills, such as they are, have always exceeded my technical skills and over the years I’ve made many projects that didn’t work, not knowing if I’d made an error or there was an error in the publication. Often it was the latter, with corrections published months later. Luckily, this was one of those projects that worked right away, and still does on the rare occasions that I use it.
I’ve taken a few screen shots on the ‘scope, one of which - if you look carefully at the dial on the generator - you’ll see is set to a sine wave of 10 MHz. The other shots show square and triangle waves. As is the way of the world, the MAX038 IC has sadly gone to same way as the 8038 – obsolete. Almost all projects these days - particularly in EPE mag (mostly sourced from ‘Silicon Chip’ mag ‘down under’ in Oz), seem to be PIC based – another skill I’ve not got into. Like the ICs, my skill-set is becoming obsolete, but I bimble along, muddling through quite contented as the world passes me by!
Hope it's of interest.
Quote of the day:
'Use what talents you possess - the woods would be very silent if the only birds that sang there were those that sang the best'.
Henry Van Dyke.
He was clever!
