I have been researching the 551B KSU, and found on the net a copy of the BSP for this unit and printed it off. It made the wiring much more understandable. However, as questions are answered and I find the documentation, other questions come up.

The first is that the BSP states that there is an optional Frequency Generator (I am assuming it is a 'ring generator') that is listed as part 118A, and the mounting bracket part number D-18069. I am assuming (correct me if I am wrong) that the frequency generator will allow the individual stations to ring eachother. Would it be aventagous to find one of these generators?

The next question is this: can I only have four stations on this system, or can I daisy chain a couple extra phones per station? I know that the maximum number of CO lines is four, but I will stick with only two for this unit. It is not all that important to have more than four stations, because all I am trying to do is show off old phones in a working system.

Again, thank you for your patients with my many questions.

Best,

Joe


Real comms took 200lb teletypes, hand keys, sounders, operators and cranked phones!