Today my friendly mailgirl delivered the 1939 Emerson radio I got off EBay. Surprised to find all 5 tubes the brand Arcturus made in usa. Unusual to find 74 year radio all same brand tubes. Those must be really good tubes or radio not been played much. Just sayin'

:Today my friendly mailgirl delivered the 1939 Emerson radio I got off EBay. Surprised to find all 5 tubes the brand Arcturus made in usa. Unusual to find 74 year radio all same brand tubes. Those must be really good tubes or radio not been played much. Just sayin'
:Are they blue????

Arcturus tubes were known to have blue glass envelopes. Didn't make them play better but they were pretty!! I have some.

Lou

The blue glass envelopes were a "spotting feature" for the earliest Arcturus tubes. Some versions of the blue-glass line of tubes did have some unique (to Arcturus) technical features but for the most part they performed like any other make tube of the same type number.

By the early 1930s most radio manufacturers had abandoned "coffin" cabinets with lift-up lids (so that proud owners could show off their bright blue Arcturus tubes to admiring visitors) and Arcturus in turn abandoned using blue glass envelopes. They also expanded their line to duplicate much of what RCA was producing. By this time the only technical feature that the tubes claimed was a "faster warmup time". How much faster this was than, say, an equivalent RCA tube, I don't know. I doubt that it could have been significantly faster without sacrificing heater life.

Some radio makers (Sparton) used Arcturus tubes in their new sets, but for the most part this tubemaker served the replacement-tube market. I don't think that they were popular tubes, at least not here in the upper midwest: in 45 years of radio collecting I have never acquired a set that had a single Arcturus tube in it.

Not sure when Arcturus went out of the tube business but I suspect that they were shut down by WW2 and never bothered to re-open.

I think tube collectors are interested in Arcturus tubes. The blue glass envelope was a marketing ploy, pure and simple.

I have an E.H. Scott Allwave 15. It has a blue-colored-glass Wunderlich tube by Arcturus as the 2nd detector. The base is red. It seems that Arcturus was "big" in somewhat limited market for Wunderlich tubes. Wunderlich's are unusual because they don't have a alpha-numeric designation. Sylvania sold Wunderlich's under its brand, but they were manufactured by Arcturus - with blue glass and red bases.

Interesting - your 1939 Emerson with all Arcturus tubes. My understanding is that Arcturus was mainly in the replacement market, not the OEM market.

Arcturus was said to be OEM tube suppliers to Sparton and (possibly) Crosley for some models; but yes, they were mostly an aftermarket tube vendor. It's not unthinkable that a radio set owner who bought into the "premium brand" hype floated by Arcturus could have re-tubed his set with all-Arcturus units- sort of like a motorcycle owner buying Avon skins both fore and aft for his favorite mount.

Jim could check for date codes on the tubes as a clue as to their origin in the radio. However, the only Arcturus tube I have, a Wonderlich, doesn't have a date code.

I have encountered at least one radio that had been re-tubed. The Airline 62-99 I had from 1934 recommended re-tubing the radio every year.
It is a dumb and wasteful idea, but I suspect some people did it.

Best regards,

Bill Grimm

:I have encountered at least one radio that had been re-tubed. The Airline 62-99 I had from 1934 recommended re-tubing the radio every year.
:It is a dumb and wasteful idea, but I suspect some people did it.
:
:Best regards,
:
:Bill Grimm
:
Thanks men for comments but I should say these not blue colored just the clear glass plain tube. By way all filaments test good

"Thanks men for comments but I should say these not blue colored just the clear glass plain tube."

Based on my Google search, it seems that Arcturus gave up on the blue-glass gimmick in the mid-1930s, going with clear glass. So, Jim, if your tubes are clear glass, that's fine.

Arcturus went belly-up in about 1940.