[Arran]

I would keep the 117Z3 unless the tube is defective, a slow warmup is not a bad thing for the B+ voltage, filter caps and all, though the tubes are pretty much instant on anyhow, in this set the battery tubes don't get their filament voltage until the rectifier tube heats up. Heat isn't really an issue in a battery tube portable, and even without the 117Z3 heater there is still the filament dropper in series with the battery tubes. If you have never worked on a tube radio before a 49-607 is not the easiest to start with, there is that AC-battery switch, and there is a shallow chassis where the speaker is mounted to the underside of, so the components tend to be clustered around the outside. That being said when you get one working they are a good performer thanks to the tuned RF amplifier stage
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