The K means constant, which lets you substitute it for a number or function (on newer calculators at least). The RV function has something to do with Bonds and maturity values
The silver trim accents can be repaired, if you so desire. Hobby shops will sell you chrome-like paint, and some liquid masking that you paint on, let dry, and then remove with an exacto knife. The paint is more of a satin silver, but you can get a chrome-like appearance by blowing on it gently immediately following application (as in a couple of seconds). Alternately, you can purchase thin mylar tape with a true chrome plating; apply the tape, let dry, and trim the excess away.
"Bare traces, no solder mask..." At the time that board was built, PCBs had only been in use for about a decade, and the problems associated with having bare traces had yet to evidence themselves. Solder mask was invented to overcome the problems associated with bare traces. The Seventies were really the dawning of the age of electronics into society. Prior to then, most functions were achieved through mechanical or electro-mechanical means. It was common to wear a wrist watch that needed to be wound every day. My uncle purchased one of the first 'remote control' televisions; it was a wired (!) control which, when pressed, would activate a motor which would change the channel up or down. Thunk! Thunk! Thunk! No other functions, such as volume, were available. In the Seventies, society met the electron. It hasn't been the same since.
It's a little late to comment but the "-M-" on the electrolytic caps probably stood for Mallory , who was likely the supplier, I've seen that emblem on some yellow polyester film capacitors before.
As mentioned by others, the "K" key allows you to set a 'constant' value that will be used in multiple subsequent calculations. The "RV" key, based on how my old Canon Canola desktop calculator works, is most likely a 'recall value' or 'recent value' function.......If for example you were entering a calculation such as 143.2 x 3.14 + 0.75443, and you had just entered the '0.75443' value but had not yet pressed the "=" key, you might wonder if you had correctly entered the previous value correctly (remember that the 0.75443 value would be when the display is currently showing at this time), so pressing "RV" would cause the display to show the previously entered value, 3.14 in this example. Some calculators would allow an additional push of the button to display even further back, 143.2 in this example.
Matt Andersen, but if you look at how it works, it seems to be recalling a previous value, which is exactly what that key does on my somewhat older Canon calculator.....
Good job on the old calculator. I remember when the came out. Beats a slip stick,
I suppose that EOF might mean Error Overflow, if the result of a calculation exceeds the largest value the calculator can display.
The K means constant, which lets you substitute it for a number or function (on newer calculators at least). The RV function has something to do with Bonds and maturity values
The silver trim accents can be repaired, if you so desire. Hobby shops will sell you chrome-like paint, and some liquid masking that you paint on, let dry, and then remove with an exacto knife. The paint is more of a satin silver, but you can get a chrome-like appearance by blowing on it gently immediately following application (as in a couple of seconds). Alternately, you can purchase thin mylar tape with a true chrome plating; apply the tape, let dry, and trim the excess away.
"Bare traces, no solder mask..." At the time that board was built, PCBs had only been in use for about a decade, and the problems associated with having bare traces had yet to evidence themselves. Solder mask was invented to overcome the problems associated with bare traces.
The Seventies were really the dawning of the age of electronics into society. Prior to then, most functions were achieved through mechanical or electro-mechanical means. It was common to wear a wrist watch that needed to be wound every day. My uncle purchased one of the first 'remote control' televisions; it was a wired (!) control which, when pressed, would activate a motor which would change the channel up or down. Thunk! Thunk! Thunk! No other functions, such as volume, were available.
In the Seventies, society met the electron. It hasn't been the same since.
It's a little late to comment but the "-M-" on the electrolytic caps probably stood for Mallory , who was likely the supplier, I've seen that emblem on some yellow polyester film capacitors before.
As mentioned by others, the "K" key allows you to set a 'constant' value that will be used in multiple subsequent calculations. The "RV" key, based on how my old Canon Canola desktop calculator works, is most likely a 'recall value' or 'recent value' function.......If for example you were entering a calculation such as 143.2 x 3.14 + 0.75443, and you had just entered the '0.75443' value but had not yet pressed the "=" key, you might wonder if you had correctly entered the previous value correctly (remember that the 0.75443 value would be when the display is currently showing at this time), so pressing "RV" would cause the display to show the previously entered value, 3.14 in this example. Some calculators would allow an additional push of the button to display even further back, 143.2 in this example.
Sigma M probably allows you to add to the number in memory
Great video!
I have a Texas instruments it 1250 pocket calculator from the 70s
RV means Real Value and CJ Bailey was correct that it is used with calculating bond maturity values.
Matt Andersen, but if you look at how it works, it seems to be recalling a previous value, which is exactly what that key does on my somewhat older Canon calculator.....
Around 16:40....what is that music?! It's so familiar, but I cannot place it.
Is it from SSX 3????
Dark Star Lounge from Mass Effect 2
ua-cam.com/video/xJDVhCjm4Yg/v-deo.html
nice stuff
You are correct "CA" means clear all.
eof end of function ?
metroid drifts !