I am advancing towards having a lovely vintage tester for testing vintage capacitors.
I have found a rather battered brake-down truck beacon inverter and powered it up from the bench power supply.
The reading accuracy is about 2% high throughout most of the range and remains consistent from 480V to 550V input voltage.
It takes 6ma from the inverter with the test terminals linked to zero ohms.
I fixed up the inverter and replaced the transistor and diode with faster parts bringing the currant draw of the inverter down by quite a bit.
I fixed the inverter core with epoxy after cleaning the silicon mastic bodge off and that got rid of all the noise it was making.
The 500V at 6ma came in with the inverter powered at 7.2 volts so we have a target for a battery pack.
I found an old 286 laptop battery with the built in processor that goes corrupt if you click a cigarette lighter close to it leaving a set of good NIMH cells to play with.
So the power unit has to fit on the two terminals and as it is a little bit heavy I have added a couple of straps that pick up the recessed cabinet screws with locating pips.
I used a couple of those screwdriver killing self tapping screws fitted with a socket naturally
I bit of SRPB made a good lower fixing with the 500V connections made all in one.
Just a charging resistor and wall wart socket for the electrics and the cover to be made and then we will be back to full service after whom knows how long.
I have found a rather battered brake-down truck beacon inverter and powered it up from the bench power supply.
The reading accuracy is about 2% high throughout most of the range and remains consistent from 480V to 550V input voltage.
It takes 6ma from the inverter with the test terminals linked to zero ohms.
I fixed up the inverter and replaced the transistor and diode with faster parts bringing the currant draw of the inverter down by quite a bit.
I fixed the inverter core with epoxy after cleaning the silicon mastic bodge off and that got rid of all the noise it was making.
The 500V at 6ma came in with the inverter powered at 7.2 volts so we have a target for a battery pack.
I found an old 286 laptop battery with the built in processor that goes corrupt if you click a cigarette lighter close to it leaving a set of good NIMH cells to play with.
So the power unit has to fit on the two terminals and as it is a little bit heavy I have added a couple of straps that pick up the recessed cabinet screws with locating pips.
I used a couple of those screwdriver killing self tapping screws fitted with a socket naturally
I bit of SRPB made a good lower fixing with the 500V connections made all in one.
Just a charging resistor and wall wart socket for the electrics and the cover to be made and then we will be back to full service after whom knows how long.
