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Voltage Regulator

 

Hello everyone.
I want to ask about the LM78L09 that used in VFO circuit in bitx40. Once I turn on the 12v power supply, the LM78L09 smoked up. Is there any possibility that the voltage regulator has been broken or it didn't strong enough to take the current from power supply? Should I use LM7809 instead?
 

The VFO does not draw enough current to heat the regulator.

I am sure you have wired the 78L09 wrongly. The various versions have different pinouts.

Yuo could post a picture and we may be able to spot the mistake.

Raj, vu2zap

At 12-05-18, you wrote:
Hello everyone.
I want to ask about the LM78L09 that used in VFO circuit in bitx40. Once I turn on the 12v power supply, the LM78L09 smoked up. Is there any possibility that the voltage regulator has been broken or it didn't strong enough to take the current from power supply? Should I use LM7809 instead?
 

Thank you for your reply..

I finally decided to change the LM78L09 with LM7809.. I think it was because the LM78L09 couldn't take the high current.?
 

The LM78L09 and LM7809 have very different pinouts and if it smoked on power up it was wired wrong.

I cannot imagine a case where the VFO used more power than a 78L09 could handle.

Allison

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