dew042 said:
siamac~ In the speaker display thingy above -- are the numbers shown with lightbulb filament? If so that pretty dern cool.
dew.
Those are ancient, they predate 7 segment Light Emitting Diodes, they are called Nixie tubes. Essentially they are neon lights Typical heights are up to 25 mm. The biggest were were 220 mm tall and go for several hundred dollars each now... :
wikipedia link on nixie tubes
From Wikipedia:
A nixie tube is an electronic device for displaying numerals or other information, in the form of a glass tube containing multiple cathodes and a wire mesh anode, filled with neon and often a little mercury and/or argon at a small fraction of atmospheric pressure. Although it resembles a vacuum tube in appearance, its operation does not depend on heating of a cathode to cause it to emit electrons (the thermionic effect). It is therefore called a cold-cathode tube, a form of gas filled tube, a variant of neon lamp.
The most common form of nixie tube has ten cathodes in the shapes of the numerals 0 to 9 (and occasionally a decimal point or two),
Connect high (170+) voltage between the desired cathode and the anode.
Nixies were used as numeric displays in early digital voltmeters, multimeters, frequency counters and many other types of technical equipment. They also appeared in costly digital time displays used in research and military establishments, and in many early electronic desktop calculators.
The Nixie display was developed by a small vacuum tube manufacturer called Haydu Brothers Laboratories, and introduced in 1954 by Burroughs Corporation, who purchased Haydu and owned the name Nixie as a trademark.
Citing dissatisfaction with the aesthetics of modern digital displays and a nostalgic fondness for the styling of obsolete technology, significant numbers of electronics enthusiasts in recent years have shown interest in reviving nixies. Unsold tubes that have been sitting in warehouses for decades are being brought out and used, the most common application being in homemade digital clocks using modern semiconductors. This is somewhat ironic, since during their heyday, nixies were generally considered too expensive for use in mass-market consumer goods such as clocks.
This recent surge in demand has caused prices to increase significantly, particularly for large tubes. The largest type, the Rodan CD-47/GR-414 (220mm [8.7 in.] tall), have been sold for hundreds of dollars apiece, but these are extremely rare and only found in a few areas of the world by persistent and fortunate seekers. Prices for other large types displaying digits over 25mm (1 inch) tall have increased by double, triple or more between 1998 and 2005.
). I was absolutely amazed at the quality of the internals. They did not scrimp on the design at all. It is filled will stryrol capacitors (seen usually in model 20s and SPECs), and expensive, low-leakage 'lytics. Seeing the internals, I would expect the phono preamps to rival those in the more expensive preamps and integrateds. I used one to push my new Yamaha M-80 power amp and AR9s, at serious SPLs. I could not find any noise or hiss I could attribute to the mixer, at all.
