Old post but just wondering how to tell a nitrogen filled relay one from not? Looking at a 3000II wondering if it's worth the trouble of dealing with the relays?
Phase Linear had numerous problems with these. Earlier 3000's had 13 relays. Later 3000's added an additional (14th) relay in order to prevent problems when using 3-head tape decks. During the production of the 3000's approximately 6 or 7 of these 13 relays were replaced with the nitrogen filled relays until eventually all 3000's had them in them.
The 3000's also suffered problems with the dirty switch contacts and false triggering of the IC's. Also the power switches can fail. It is also best to obtain a copy of the service manual as there are some other mods that should be performed.
NOTE: The nitrogen gas-filled sealed relays with gold contacts had a yellow top.
Ed