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

Re: [softrock40] RXTX Q2 driver heatsink hot

Expand Messages
  • FRANCIS CARCIA
    heat sink on a 2222, sounds over stressed. Tony Parks wrote: Hi Rick, The heatsink on the 2N2222A driver transistor runs pretty
    Message 1 of 3 , Feb 1, 2007
    • 0 Attachment
      heat sink on a 2222, sounds over stressed.

      Tony Parks <raparks@...> wrote:
      Hi Rick,
       
      The heatsink on the 2N2222A driver transistor runs pretty warm but so far that has not been a problem.  The emitter voltage should be around 1.5 volts with no RF drive.
       
      I would recomend staying within the 1 watt RF output to be sure the output of the RXTXv6.1 is meeting FCC requirements.
       
      73,
      Tony KB9YIG
       
      ----- Original Message -----
      Sent: Thursday, February 01, 2007 3:37 PM
      Subject: [softrock40] RXTX Q2 driver heatsink hot

      Tony, the TX part of my new RXTX seems to be working with the IQ test
      tones, but Q2, the TX driver transistor, has a heatsink that is
      getting almost too hot to touch after a couple minutes at full power.
      Is this normal? Should this part have a little bigger heatsink? What
      should be the voltage at the emitter when there is no RF drive to mess
      with my voltmeter?

      Also I have the Ramsey 40 Meter power amplifier kit built and ready to
      connect to the RXTX, but it will only put out half its rated 20 watts
      of power with 1 watt drive from the RXTX. Can I feed the RXTX with
      13.6 volts instead of 12 to get a little more power out of the Ramsey
      PA? Would I need bigger heatsinks?


    Your message has been successfully submitted and would be delivered to recipients shortly.