Homebrew Multiband SSB Transceiver part 1

For radio amateurs who enjoy making their own equipment Sure hope some time to make homemade multiband transceiver. Here the author deliberately design a display-oriented SSB transceiver with components that are easy to make and with components easily available in the market. The block diagram of multiband transceiver like the following:

Figure 1 Multiband SSB Transceiver diagram

From the diagram above transceivers today I want to explain important points only gradually and is the key to the design, are:
1. Make a SSB filter
2. Creating IF amplifier transformers
3. Creating Exciter
4. Making the system PLL VFO for each band ( 3.5, 7, 14, 21, 28 MHz).
5. Creating the DDS VFO (Direct Digital Synthesizer)
6. Digital display.