¿ªÔÆÌåÓý

ctrl + shift + ? for shortcuts
© 2025 Groups.io
  1. QRPLabs
  2. Messages
Single Messages Topics Expanded Polls

Re: #QMX #HighBand #LowPower QMX High-Band Working but with Low Power out #qmx #HighBand #LowPower

 

Roy,

I strongly advise you try to figure out root cause before you replace the bad transistor.

?At a minimum, disable the power source to the PA by lifting a leg of L502, or removing it completely.?

Now you can measure gate drive voltages while not risking another transistor failure. Make certain IC503 has not failed.

JZ

On Thu, Apr 4, 2024, 11:01?AM Roy - KI0ER <ki0er@...> wrote:
On my "hot" BS-170, the Drain and Gate show a direct internal short.

So the question is, if I just replace that one, am I good, or more likely, I need to find the root cause of why it went bad ... unless it's just that I over tightened the heat sink assembly?

Thank you so much John and Ludwig for jumping in to help this novice EE (I'm a retired software engineer actually)!
--
73
de Roy - KI0ER
Littleton, Colorado USA

Join [email protected] to automatically receive all group messages.