My first attempts at full-scale PLL synthesis were using TTL and were notably unsuccessful. Some early articles in ham magazines described TTL frequency dividers, which would not reliably divide by the numbers they were supposed to! I was led up the garden path on this! However I did manufacture a working optical rotary encoder and get a PARALLEL data generator and LED display working for the ham bands (lots of wires). The power demands of the TTL and LEDS were rather horrendous.
At about the same time I constructed a VFO/PLL LO system based on the frequency scheme used in the old Kenwood TS120S -but using my own simplified and rather different circuitry. The Kenwood is a single conversion rig with an 8.83 MHz I.F. This VFO/PLL LO was successful, but the construction method used was rather bulky, and I really wanted to build something fully synthesized, so it has sat in a box for some years.
The mixing frequency scheme used in the TS120S seemed to receive little attention in amateur literature at the time, but it really deserves consideration by the home-brewers of today, as it offers passband tuning and a flexible I.F. choice in the 8 to 9 MHz range, and all ham-band coverage, derived from a 10 MHz crystal and 5.5 to 6 MHz VFO (or synthesizer).
Have a look at the Ten-Tec website and read about the benefits of single conversion receivers with narrow crystal filters in the description of their new Orion transceiver.
Currently most home brewers seem to be moving to DDS synthesized local oscillator systems controlled by microprocessor, but so far I haven’t figured out a cost-effective DDS system to suit my needs (really low-cost!). I’m still thinking!