Robert T
Member level 1
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I have a TIP50 shunting to ground at the end of a LF signal pulse. The purpose is to ground the antenna to remove the "ring down".
This has been working well until the other day when the TIP50 failed (died?) - I assume that even though the TIP50 was switching to ground after the signal was switched off, the voltage is still too high even though for such a short period of time.
TIP50 is rated at 450V.
The signal on the antenna is 900V peak to peak.
The signal is switched to 0V in 120usec with the TIP50.
I tried a BU505 which is rated at 1500V however it does not switch as the TIP50 did. Takes the antenna 1.5msec to ring down.
I have tried decreasing the value of the base resistor with the BU505but this has no effect.
Is anyone able to advise me please as to a solution for this issue. Maybe a more suitable transistor?
Thanks, Robert
This has been working well until the other day when the TIP50 failed (died?) - I assume that even though the TIP50 was switching to ground after the signal was switched off, the voltage is still too high even though for such a short period of time.
TIP50 is rated at 450V.
The signal on the antenna is 900V peak to peak.
The signal is switched to 0V in 120usec with the TIP50.
I tried a BU505 which is rated at 1500V however it does not switch as the TIP50 did. Takes the antenna 1.5msec to ring down.
I have tried decreasing the value of the base resistor with the BU505but this has no effect.
Is anyone able to advise me please as to a solution for this issue. Maybe a more suitable transistor?
Thanks, Robert