| Products > Test Equipment |
| High Voltage Bipolar Replacement type(s) for MJ16012 in HP 8663A ? |
| (1/1) |
| Uky:
Greetings. I picked up an HP 8663A on a flea market with a not working inverter. The design uses two high voltage bipolar transistors MJ16012. One of them was broken and one of the electrolythinc capacitors in the same circuit was "boiled" (short circuited). I was able to repair the inverter, replacing the transistors with BUX48 that I had in my junk box but now my supply of bipolar high voltage types are depleted. DigiKey and Mouser lists a few types that are still produced and most likely available. The BUX48 had specifications that was "near" those of the MJ16012 but I do not know if my choise will be long lived. About one hour after having had the instrument in operation, I turned the instrument OFF, disconnected the AC (pulled the plug), quickly removed the inverter PCB and tried to asess if there were any signs of thermal stress on the replaced components. They were all att room temperature. At least not any signs of heat dissipation in the electrolythic capacitors ((2x10 uF/350V) x 2) As I have read, there are more than one enthusiast that has had problems with this inverter board. If any one would be willing to share what other type(s) of high voltage bipolars that worked I would be grateful. Cheers Ulf Kylenfall SM6GXV |
| Navigation |
| Message Index |