As the price of electronic parts has dropped, it has become more practical to build complete transceivers, as opposed to separate receivers and transmitters. This avoids the practical problem of muting a modern transceiver--a common receiver feature often omitted today.

• An Optimized QRP Transceiver for 7 MHz
  ARRL Handbook 1993, pp. 30-37 to 30-40
  Here is a rig that provides a real challenge for the QRP home builder. Nonetheless, this is a classic circuit and a favorite in the QRP community. 
• A QRP SSB/CW Transceiver for 14MHz -- Part 1
  QST December 1989, pp. 18-21
  Exotic circuitry and hard to find components aren't necessary if you want to build excellent performance into a home-brew SSB/CW transceiver: Careful design is the key. 
• A QRP SSB/CW Transceiver for 14MHz -- Part 2
  QST January 1990, pp. 28-31
  W7ZOI rounds out his description of a 1- or 10-W SSB/CW rig with details on its transmitter, TR switching and optional speech processor. 
• The QRP Three-Bander 
  QST October 1989, pp. 25-30
  This low-power, direct-conversion CW trnsceiver covers 18, 21 and 24 MHz, and includes sidetone, spotting and relay-less full break-in --- all on one circuit board!

40 meter rig with SSB (voice) and CW (Morse code) operating modes by Steven "Melt Solder" Weber KD1JV.