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kens - Are the collectors of the output transistors on the amplifier boards connected to the metal can? I can see from the photo that the heatsinks don't touch
by chiph 1y ago
kens - Are the collectors of the output transistors on the amplifier boards connected to the metal can? I can see from the photo that the heatsinks don't touch (there's a gap between them for the capacitors). Did they use nylon screws to prevent an electrical path through the frame?
- kens 1y agoIt's probably too late for anyone to see this, but I got an answer from CuriousMarc on the transistors: "The collectors are connected to the cans, but there is a coat of insulator on the heatsinks under the transistors on some models or on the whole heatsink on others, so the heatsinks are electrically isolated from the transistors."
- kens 1y agoUnfortunately, I don't have the FDAI handy to check this.
- CamperBob2 1y agoFor TO-5 bipolars, it was common for the collector to be connected to the case. I wouldn't say that's universally true but I don't recall any exceptions off the top of my head.
- chiph 1y agoI think it's "generally" true. I saw a mention of some where the transistor had 4 pins: Emitter, collector, base, and ground (can). Presumably for RF shielding and they wanted a higher quality connection to the can without soldering/clamping it directly.