Tony Duell quoted me as having written: Good point. I still use a tone-dial 746 as one of my phones and a rotary dial 300-series wall mount version (don't know the number) as my other. The only two reasons I don't use my type 332 are 1) the induction coil is dead and 2) I have now borrowed microphone and speaker diaphragm to keep the wall mount one going. Another note for US types. Type 330 and its derivatives = pre-war design of phone. My 332 actually has cloth insulation on internal wires, although the (much rarer) wall mounted one has plastic insulation. Late 1950s (?), much lighter design, PCB based, introduced, called 706. As components got smaller, the number and size of PCBs reduced, and the 746 has all the components, including the line drop compensator (resistors, diodes, light bulbs) on a single PCB. This design remained in use for around 20 years - PCB from phone circa 1970 interchangeable with PCB from phone circa 1990, the main difference being the size of the capacitors and (if you're lucky) the provision of a few extra screw terminals. (dial, bell, handset etc. all terminated with ring or fork (spade) terminals to screw onto these). I keep several type 746 phones in stock - people still occasionally want rotary dial phones... I've only ever seen one version, but then again, I've never seen a schematic that actually gives the resistor values. Could be what I was thinking of. Philip.