Studied the Farnell power supply schematics a lot when I first got the idea to make my own power supply. It'd be nice to find one of these and modernise it a bit, though I'm sure plenty of people would yell at me if I did that!
Been there!........I got a lot of flack for modifying my LT30-2, I started to replace the meters with LCDs.........and ended up reversing it all and putting it back stock.....:-)
Had to replace a BC182L to get one running but it was also spot on for calibration after years in dad's loft. I'm missing all the same parts, probably lost when whoever tried and failed to fix it before dad picked it up.
I have just got one and try to set the calibration and zeroing the meter put the calibration out so I set it for 30 volts and the set for15 volts and then adjust the meter to read 15 volts.
From my experience all my bench PSU's at max voltage are above rated so I would have left it at 31.5V as it was but set the output to 30V for meter calibration.
Hi Ian, great video mate I have the LB/30 1amp could you please advise what I could use to calibrate the current loadwise I dont have an electronic load, many thanks Ian.
Use lots of hefty wirewound resistors in series/parallel as required (use Ohm's Law) and mounted on a fireproof insulating board , or make an electronic load with a power MOSFET driven by an OP-AMP (best solution).
Hi Ian... Did you do that cal with no load on it, you may find that the output volts could be a little different, even with a small load, just thought I would mention it :) I am referring to the 5 minute mark in the video
SOT means - 'Select On Test' Or, put in the component value that best makes the test result you want. If you lifted one end of the R12 off the board to get a correct reading of its value, and it still measures many Kohms out, replace it.
Looks great Ian, and those bezels you made really finish it off nicely 👍
Wonderful job! Love the 3D printed edge pieces! Lovely little PSU!
That was a nice job, it's great to see these Farnell's being restored rather than going to landfill
Excellent touch with the bezel!
Nice finished restoration!
Studied the Farnell power supply schematics a lot when I first got the idea to make my own power supply. It'd be nice to find one of these and modernise it a bit, though I'm sure plenty of people would yell at me if I did that!
Been there!........I got a lot of flack for modifying my LT30-2, I started to replace the meters with LCDs.........and ended up reversing it all and putting it back stock.....:-)
Had to replace a BC182L to get one running but it was also spot on for calibration after years in dad's loft. I'm missing all the same parts, probably lost when whoever tried and failed to fix it before dad picked it up.
Looks proper smart. Thanks Ian :)
You need a Roband Varex 30-2. They are a great liniar. As I work for them I would say that I suppose. Very stable and great regulation.
Nice save !
I have just got one and try to set the calibration and zeroing the meter put the calibration out so I set it for 30 volts and the set for15 volts and then adjust the meter to read 15 volts.
From my experience all my bench PSU's at max voltage are above rated so I would have left it at 31.5V as it was but set the output to 30V for meter calibration.
I did think about it (as noted in the video) but thought what the hell......🙂
great video, could you please tell me what make and model of electronic variable load you are using? as I'm looking to purchase one
Hi Ian, great video mate I have the LB/30 1amp could you please advise what I could use to calibrate the current loadwise I dont have an electronic load, many thanks Ian.
Use lots of hefty wirewound resistors in series/parallel as required (use Ohm's Law) and mounted on a fireproof insulating board , or make an electronic load with a power MOSFET driven by an OP-AMP (best solution).
Hi Ian... Did you do that cal with no load on it, you may find that the output volts could be a little different, even with a small load, just thought I would mention it :) I am referring to the 5 minute mark in the video
There is about 4mV difference on the output @30Vdc between no load and the full 1A load. But yes, I should have mentioned that for clarity.
Me again Ian sorry to bother you but can you explain what SOT means on resistor R12 measures 13.8kohm colours say it should be 8.2kohm, cheers.
SOT means - 'Select On Test'
Or, put in the component value that best makes the test result you want.
If you lifted one end of the R12 off the board to get a correct reading of its value, and it still measures many Kohms out, replace it.