I would like to share Shane L. Larson's blog post, Cosmos 11: The Persistence of Memory.
Our digital society just keeps changing and my boxes of floppy disks are looking for some device to read them.
The CompuPro S-100 bus computer has gone the way of electronic recycle and the 8 inch floppies have no one to read them.
I still have book shelves, although many of the books are rusty red with acid age.
Hopefully the newer ones that are made with acid-free paper will survive longer.
What would some future generation ask of us if they had nothing but our empty cities to look at?
- LRK -
Cosmos 11: The Persistence of Memory
Times change, new inventions hit the market, old devices end up in the trash.
There is a box of vacuum tubes (valves to some) out there in the garage looking for a roll chart tube tester.
They came out of my desk in my room over my folks garage that I slept in as a teenager.
Now no more as the house and garage were sold and have been replaced with two houses and two garage apartments.
No secret vault behind the removable rock in the rock wall next to the patio fireplace. Gone, making room for that second garage apartment.
- LRK -
A valve amplifier or tube amplifier is a type of electronic amplifier that makes use of vacuum tubes to increase the amplitude of a signal. Low to medium power valve amplifiers for frequencies below the microwaves were largely replaced by solid state amplifiers during the 1960s and 1970s. Valve amplifiers are used for applications such as guitar amplifiers, satellite transpon
ders such as DirecTV and GPS, audiophile stereo amplifiers, military applications (such as radar) and very high power radio and UHF television transmitters.
From the 1970s the silicon transistor became increasingly pervasive. Valve production was sharply decreased, with the notable exception of cathode ray tubes (CRTs), and a reduced range of valves for amplifier applications. Popular low power tubes were dual triodes (ECCnn, 12Ax7 series) plus the EF86 pentode, and power valves were mostly being beam tetrode and pentodes (EL84, EL34, KT88 / 6550, 6L6), in both cases with indirect heating. This reduced set of types remains the core of valve production today.
The Soviets retained valves to a much greater extent than the West during the Cold War, for the majority of their communications and military amplification requirements, in part due to valves' ability to withstand instantaneous overloads (notably due to a nuclear detonation) that would destroy a transistor .
The dramatic reduction in size, power consumption, reduced distortion levels and above all cost of electronics products based on transistors has made valves obsolete for mainstream products since the 1970s. Valves remained in certain applications su
Thanks for looking up with me.
- LRK -
Web Site: http://lkellogg.vttoth.Telco style rotary stepper relay
RSS link: http://
RSS link: http://
The Pioneer plaques are a pair of gold-anodized aluminium pla
ques which were placed on board the 1972 Pioneer 10 and 1973 Pioneer 11 spacecraft, featuring a pictorial message, in case either Pioneer 10 or 11 is intercepted by extraterrestrial life. The plaques show the nude figures of a human male and female along with several symbols that are designed to provide information about the origin of the spacecraft.
The Pioneer spacecraft were the first human-built objects to leave the Solar System. The plaques were attached to the spacecraft's antenna support s
truts in a position that would shield them from erosion by stellar dust.
WHAT THE MIND CAN CONCEIVE, AND BELIEVE, IT WILL ACHIEVE - LRK -