Disable and bypass the 6000 series final amplifier via sortware or hardware for QRP?

  • 1
  • Idea
  • Updated 3 years ago
  • Not Planned

There have been discussions about the current draw when biasing the 6000 final amplifier, see https://community.flexradio.com/flexradio/topics/current-drain-on-6300?topic-reply-list%5Bsettings%5... for one.

Does, or can, the final amplifier be bypassed and not keyed up on transmit?  The preference would be via an API call from SmartSDR Tx setup, or by a physical process such as removing the final and jumpering connectors.

Last FD we ran 3AB with (literally) a ton of batteries but the Flex was left behind due to exceeding the current budget of 7A for rig, computer and monitor(s).

It would be nice to flip a switch on SmartSDR (or Maestro) to turn on/off QRP reducing the associated battery draw.

Photo of Stan - VA7NF

Stan - VA7NF

  • 401 Posts
  • 85 Reply Likes

Posted 3 years ago

  • 1
Photo of N3NER

N3NER

  • 186 Posts
  • 24 Reply Likes
I may be wrong here but I would think just reducing the power down to QRP levels would do the same thing.
Photo of Stan - VA7NF

Stan - VA7NF

  • 401 Posts
  • 85 Reply Likes
The finals are class AB and draw an estimated 5A just for bias, then add the power out.  If the driver can be routed to the antenna switching then it becomes a super QRP rig that will draw around 2A rather than the current 7A.
Photo of Jim Hawkins / K2JHV

Jim Hawkins / K2JHV

  • 28 Posts
  • 8 Reply Likes
I've gotten mine down to less than 4 watts.  The guy at the other end asked me to increase it again because he was no longer copying me well enough.  (SWR 1:1).
My amp, on standby, has a input power meter.
Photo of Jim Hawkins / K2JHV

Jim Hawkins / K2JHV

  • 28 Posts
  • 8 Reply Likes
My amp also has a power meter when it's not on standby. HI ;-)
Photo of K2CM

K2CM

  • 265 Posts
  • 18 Reply Likes
Buy a Flex 1500...very good QRP radio... Available used for $500 give or take a bit.
(Edited)