Tube ID Clarification

[marty pollard]

Does the 'stop sign' shape (elongated or not) ALWAYS mean RCA?
I've got a Hammond ax7 with that ID mark.
I've got a bunch of other brands with the same mark.

There are no other manufacturer marks to ID dates and such.

In orange lettering it says:
HAMMOND
59-22
274


Can we glean any info from that or is it just inventory/replacement information specific to Hammond?

[Anywho]

274 is the EIA code for RCA. The other set of numbers is the production date code I would think.

[rockon1]

274 as Anywho stated is an RCA code however a pic is worth a bunch of words. Ive seen the elongated stop sign on other tubes. If yours is a grey plate (long or short) and has two flats sides on the mica's then its an RCA.

[Blue Strat]

Does the 'stop sign' shape (elongated or not) ALWAYS mean RCA?
I've got a Hammond ax7 with that ID mark.
I've got a bunch of other brands with the same mark.

There are no other manufacturer marks to ID dates and such.

In orange lettering it says:
HAMMOND
59-22
274


Can we glean any info from that or is it just inventory/replacement information specific to Hammond?

As they both said, the EIA code of 274 is the clincher here. "Stop Sign" markings can also be found on Tung Sols and Sylvanias (at least).

[Timbre Wolf]

Does the 'stop sign' shape (elongated or not) ALWAYS mean RCA?
Definitely not. Many manufacturers used that shape around the tube number.

- Thom