Loading ...
Sorry, an error occurred while loading the content.

Re: Ensemble RXTX - Stage 5 Testing

Expand Messages
  • g8voip
    Hi Joel, Personally that is one particular test which I have severe reservations about, and think it might well contribute to a number of the failures of FETs
    Message 1 of 3 , Mar 27, 2011
    • 0 Attachment
      Hi Joel,

      Personally that is one particular test which I have severe reservations about, and think it might well contribute to a number of the failures of FETs that some people have experienced in that area.

      I suspect it might depend on the terminal voltage of the meter being used, polarity, or simply slipping and shorting to something else.

      I think it is sufficient just to measure the voltage on the junction of R51 / R50, i.e the gate of Q10 when the PTT is active, should be around 8V which will turn Q10 on.

      Most people have successfully carried out that test as described in Robby's notes without any ill effects, but there have also been a number of unexplained failures of Q10 and Q9.

      I could be totally wrong of course :)

      73, Bob G8VOI


      --- In softrock40@yahoogroups.com, Kevin Morgan <kmorgan6@...> wrote:
      >
      > On 3/27/2011 12:27 PM, Joel Black wrote:
      > > I am steadily making progress on my Ensemble RXTX and am about 1/2-way
      > > through stage 5 - RF I/O and Switching. I wound and installed the
      > > inductors and was testing them for continuity but noticed I have to have
      > > the switching transistors and power applied to the board to test L4.
      > > This is for a continuity check? I tested for continuity from the of
      > > source Q10 to the North contact of C39. Am I screwy or am I supposed to
      > > be checking for something else?
      > >
      > > 73,
      > > Joel - W4JBB
      > Hey Joel,
      > You're checking for continuity along the RX RF path and Q10 needs
      > to be turned on to do it. I know, it's very hairy checking for
      > continuity with power applied--goes against everything I was taught in
      > ET school. But it works.
      >
      > 73, Kevin AB2ZI
      >
      > --
      > Kevin J. Morgan AB2ZI<kmorgan6@...>
      > -------------------------------------------------------------------------------
      > My Webshots Photos http://community.webshots.com/user/kmorgan631
      > -------------------------------------------------------------------------------
      >
    Your message has been successfully submitted and would be delivered to recipients shortly.