Possible Lead for Old Equipment

**bigburtchino** · 03-21-2014, 05:37 PM

I find the best way to identify old electronics is with the EIA code. Stands for Electronic Industries Association, I believe the Association started during WWII but not certain on that. This association wrote the first standards specifications for the industry. EIA has evolved into today's TIA - Telecommunications Industry Association. Still doing the same thing as the old EIA just encompassing a whole lot more industry standards. This was the start of agreed upon standards that has allowed among many things, common vacuum tube sockets, IC chip data sheets, and agreed upon size of connectors. They are still trying to agree on AC adapters (why we have so many). With old electronics, components like speakers, transformers and rheostats are good places to look for EIA codes. As most manufacturers of these components belonged to the EIA, thus utilized EIA date codes. The first EIA date codes were 6 digit codes and I think it was 1969 they switched to 7 digit codes (adding 2 digit year code). Anyway it's a sure way to date old electronics with a little effort. Example 285150 - the first three digits is always the company that made it, 285 is the old Rola speaker company - 1 is the year of manufacture could be 1951 or 1961 - last two digits is the week of manufacturing. Try to focus on easy to identify components that have multiple applications (speakers/transformers). Capacitors and even switches can be hard as there are so many types and makers. With speakers everyone knows what they are and just a handful of makers. Google EIA date codes will get you more details if I haven't bored you to death already! LOL

**Lurch** · 03-21-2014, 06:45 PM

Originally Posted by bigburtchino

I find the best way to identify old electronics is with the EIA code. Stands for Electronic Industries Association, I believe the Association started during WWII but not certain on that. This association wrote the first standards specifications for the industry. EIA has evolved into today's TIA - Telecommunications Industry Association. Still doing the same thing as the old EIA just encompassing a whole lot more industry standards. This was the start of agreed upon standards that has allowed among many things, common vacuum tube sockets, IC chip data sheets, and agreed upon size of connectors. They are still trying to agree on AC adapters (why we have so many). With old electronics, components like speakers, transformers and rheostats are good places to look for EIA codes. As most manufacturers of these components belonged to the EIA, thus utilized EIA date codes. The first EIA date codes were 6 digit codes and I think it was 1969 they switched to 7 digit codes (adding 2 digit year code). Anyway it's a sure way to date old electronics with a little effort. Example 285150 - the first three digits is always the company that made it, 285 is the old Rola speaker company - 1 is the year of manufacture could be 1951 or 1961 - last two digits is the week of manufacturing. Try to focus on easy to identify components that have multiple applications (speakers/transformers). Capacitors and even switches can be hard as there are so many types and makers. With speakers everyone knows what they are and just a handful of makers. Google EIA date codes will get you more details if I haven't bored you to death already! LOL

Not at all. That was very helpful. Thank you