UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post - Rectangular 8-Pin Plug and Socket Connectors

David Dunlop · 26th Sep 2018, 3:53 pm

This will no doubt be an interesting research journey, Richard. So far, two major parameters have surfaced that ‘outline’ the needs which promoted the development of this type of connector. One is that very high voltages and amperage are involved with the wireless equipment being designed. The second is that it is expected frequent removal of the wireless components from their cases, for routine maintenance, is expected so a quick reliable means of connect/disconnect is useful. The 52-Set and Navy equipment built by Canadian Marconi certainly fit that bill. The connectors in the photo I posted from a friend are from a piece of navy equipment CMC built.

I am going to have to disassemble one of these sockets on the back of my 52-Set Remote Receiver soon (just waiting for a spare socket to arrive) as one of the leaf contacts has been broken away and I have a nagging hunch the resulting loose hardware has bounced around inside the connector resulting in a short between the HT and LT feeds. Want to study the item before attempting the repair.

From what I have been told, the back of these connectors used on the Canadian 52-Sets has nothing more than ‘CMC’ cast into the Bakelite. I am assuming from that information the connectors used on Canadian Marconi Wireless Sets No. 9 will be similarly marked. If British connectors have STC on them my suspicion would be the item was not a third party design as some form of patent acknowledgement would be expected. STC may have developed the design and simply made it available to CMC during the war.

But there must be paperwork somewhere. I think I now need to find a copy of the British Master Parts List for the No. 9 Set and see if these connectors show up in it, and what, if any, additional clues might be present.

David

26th Sep 2018, 3:53 pm	#4
David Dunlop Pentode Join Date: Oct 2013 Location: Winnipeg, Canada Posts: 116	Re: Rectangular 8-Pin Plug and Socket Connectors This will no doubt be an interesting research journey, Richard. So far, two major parameters have surfaced that ‘outline’ the needs which promoted the development of this type of connector. One is that very high voltages and amperage are involved with the wireless equipment being designed. The second is that it is expected frequent removal of the wireless components from their cases, for routine maintenance, is expected so a quick reliable means of connect/disconnect is useful. The 52-Set and Navy equipment built by Canadian Marconi certainly fit that bill. The connectors in the photo I posted from a friend are from a piece of navy equipment CMC built. I am going to have to disassemble one of these sockets on the back of my 52-Set Remote Receiver soon (just waiting for a spare socket to arrive) as one of the leaf contacts has been broken away and I have a nagging hunch the resulting loose hardware has bounced around inside the connector resulting in a short between the HT and LT feeds. Want to study the item before attempting the repair. From what I have been told, the back of these connectors used on the Canadian 52-Sets has nothing more than ‘CMC’ cast into the Bakelite. I am assuming from that information the connectors used on Canadian Marconi Wireless Sets No. 9 will be similarly marked. If British connectors have STC on them my suspicion would be the item was not a third party design as some form of patent acknowledgement would be expected. STC may have developed the design and simply made it available to CMC during the war. But there must be paperwork somewhere. I think I now need to find a copy of the British Master Parts List for the No. 9 Set and see if these connectors show up in it, and what, if any, additional clues might be present. David