Tuesday, October 12, 2021
IBM had Pascal in 1957!
No, not Turbo Pascal. Pascal's adder.
Continuing my 1957 IBM theme:
IBM's field engineers sometimes needed to figure in hexadecimal. IBM made sure its engineers were equipped with superdeluxe pocket-size hex calculators.
But they weren't electronic. IBM's engineers were using the original mechanical adding machines while servicing the most advanced electronic sorting machines.
I saw this on Ebay and had to buy it. Closeup view:
On the back it says MADE IN USA, and lists Patent number 2797047. The patent (for decimal, not hex) was granted to Sterling Plastics in New Jersey in 1957.
Somebody had scratched 'Bad Carry' on the back, but the carry action works fine. It just needed to be loosened up. The only problem is that it doesn't have a convenient way to reset to zero. The older Addometer pictured above it had a reset lever.
Sterling sounded familiar but I couldn't place it at first. I have several slide rules made by Sterling.
The Slide Rule Museum gives a history of Sterling and shows its decimal adders, which were sold commercially. Presumably the hex version was a special 'fleet order' for IBM.
I saw this on Ebay and had to buy it. Closeup view:
On the back it says MADE IN USA, and lists Patent number 2797047. The patent (for decimal, not hex) was granted to Sterling Plastics in New Jersey in 1957.
Somebody had scratched 'Bad Carry' on the back, but the carry action works fine. It just needed to be loosened up. The only problem is that it doesn't have a convenient way to reset to zero. The older Addometer pictured above it had a reset lever.
Sterling sounded familiar but I couldn't place it at first. I have several slide rules made by Sterling.
The Slide Rule Museum gives a history of Sterling and shows its decimal adders, which were sold commercially. Presumably the hex version was a special 'fleet order' for IBM.Labels: Happy Ending, new toy
¶ 1:50 PM
Sunday, June 06, 2021
Astrometeorology 4: Maragha and astrolabes
I'm running slow on graphics lately. I'm weary and used up. Now that the holocaust is starting to ease, maybe I can recover my graphical gumption.
Continuing the theme of astrometeorology, focusing this time on a side trip into the Islamic history of astronomical instruments. I'll return to the main theme of solar magnetic fields in the next entry.
Astrolabes were developed first in Greece at the time of Ptolemy. The Arabs and Persians picked up the subject and the instruments around 800 AD. They expanded the subject and the instruments in their tireless effort to measure and predict the patterns of weather and civilization.
An astrolabe is an observational instrument AND an analog computer, all in one. Ordinary telescopes are only observers. Slide rules are only computers. I can't think of a similar combined tool in other areas of science, at least before the electronic era. (The anti-aircraft sound detector was an acoustical astrolabe, developed after electronics but not using electronics.)
An observatory at Maragha near Tabriz in northern Persia was a center of study and invention. Maragha built small Greek-style astrolabes as well as huge building-size instruments. Archeologists have restored it and figured out how the various instruments worked.
This is the tool that archeologists call Instrument 3. It's a simple sighter for both azimuth and altitude. Polistra is trying to realign with the beacons of the universe.
The sighting bar with two pinholes or gunsights is the alhidade. It's the key element of these instruments and astrolabes.
Below is a scope-like tool. It didn't include a lens; the scope was apparently just to shield your eyes from ambient light while observing moon and stars in partial daylight.
Why no lenses? My first thought was that glass wasn't available, but that's exactly wrong. Glass technology was highly developed in that part of the world 15000 years ago in the Bronze Age, and many practical and artistic glass items were found in the same place and era as the observatory. Even worse, some of the scholars who wrote about the observatory ALSO wrote in detail about glass technology. So refined glass tech was right there in the same place and in the same minds. Why didn't they look at the moon through the bottom of a bottle and think Eureka? We'll never know.
= = = = =
Later addition: Instrument 11. This one was unique in its ability to switch measurement modes.
The vertical measuring stick pivoted on the horizontal rod so that it could be used two ways:
When the measuring stick was horizontal, it measured the azimuth:
And when the measuring stick was vertical, it measured the altitude of the alidade:
= = = = =
Here Polistra is using an astrolabe inside one of Maragha's giant azimuth dials.
= = = = =
Astrolabe makers were highly valued and famous artisans. One of the best was a Syrian named Mariam, here in a picture from the 1001 Islamic Inventions website.
Also from that website:
The starmap pointer is the rete (net), including specific labeled extensions for major stars. The upper circular part is used in calculations, and can be turned independently on some versions. The rete corresponds to the slider (B and C scales) on a slide rule.
On top of the rete is the rule, corresponding to the cursor on a slide rule.
The unique part is the alhidade, on the back. As with the big instruments, you sight through the pinholes to determine height of a star or sun. You could also lay the astrolabe flat on a table or pillar, line up with north, and use the alhidade to sight an azimuth.
= = = = =
Jumping from 800AD to right now:
I bought an astrolabe kit from Dreipunkt in Germany. They make a variety of kits and learning toys. The kit is an interesting mix of old materials and new methods. It's entirely made of wood. Even the axle and joining pegs are wood. The wood comes in a hi-tech form, three VERY thin laminated layers, and the pieces are cut by lasers. I built it in one hour with no errors, despite my complete lack of wood skill. No tools or glue needed, except for some careful hammering of the joining pegs. Dreipunkt must have done some heavy Murphy testing on their instructions if even a wood-idiot like me can get it right!
Real astrolabes were kit-like. The horse cotterpin allowed you to remove any of the pieces, or switch the starmap plate to different maps or latitudes. Dreipunkt custom-printed a starmap for my location, labeled Spokane!
Back side with alhidade:
Front with rete:
Blurry closeup of the location:
I tried following the directions to determine the time of day, which isn't really useful now but would have been routine in 800 AD before clockwork.
I used the Alhidade to measure the height of the sun over the horizon, sighting through the two pinholes. 18 degrees above horizon.
Then I re-used the Alhidade to locate the 'starsign date' from today's date. June 6 = Gemini + 16 degrees.
Then I turned the Rete to line up Gemini+16 with the great circle for 18 degrees on the Plate. 18 is between 10 and 20, with no finer lines, so this didn't feel very accurate.
Then I turned the Rule to the same Gemini+16 on the Rete, and read off the time on the Mater. Appeared to be about 6:05. The clock time when I sighted the sun was 6:13 standard time, so this isn't too bad for a first try! (Later, used an online calculator to get solar time from standard time, and the astrolabe is about 15 minutes from solar time.)
= = = = =
Astrolabes should have spawned circular slide rules but for some reason they didn't. The linear slide rule developed from Napier's Bones, and the circular slide rule or wheel chart developed much later. None of those rules included the measurement tool, so astrolabes (and their descendants like sextants) are still unique.
= = = = =
Later footnote: Yes, the horse was a cotterpin.
The sighting bar with two pinholes or gunsights is the alhidade. It's the key element of these instruments and astrolabes.
Below is a scope-like tool. It didn't include a lens; the scope was apparently just to shield your eyes from ambient light while observing moon and stars in partial daylight.
Why no lenses? My first thought was that glass wasn't available, but that's exactly wrong. Glass technology was highly developed in that part of the world 15000 years ago in the Bronze Age, and many practical and artistic glass items were found in the same place and era as the observatory. Even worse, some of the scholars who wrote about the observatory ALSO wrote in detail about glass technology. So refined glass tech was right there in the same place and in the same minds. Why didn't they look at the moon through the bottom of a bottle and think Eureka? We'll never know.
= = = = =
Later addition: Instrument 11. This one was unique in its ability to switch measurement modes.
The vertical measuring stick pivoted on the horizontal rod so that it could be used two ways:
When the measuring stick was horizontal, it measured the azimuth:
And when the measuring stick was vertical, it measured the altitude of the alidade:
= = = = =
Here Polistra is using an astrolabe inside one of Maragha's giant azimuth dials.
= = = = =
Astrolabe makers were highly valued and famous artisans. One of the best was a Syrian named Mariam, here in a picture from the 1001 Islamic Inventions website.
Also from that website:
The making of astrolabes, a branch of applied science of great status, was practiced by many including one woman from Aleppo, Mariam “Al-Astrolabiya” Al-Ijliya, who followed her father’s profession and was employed at the court of Sayf al-Dawlah (944 - 967 AD), one of the powerful Hamdanid rulers in northern Syria who guarded the frontier with the Byzantine empire in the tenth century.Hmm. Aleppo. Sounds familiar. Isn't that one of the horrible anti-womxn Muslim places that Hillary enlightenedly bombed down to bedrock in order to bring Enlightened Womxns Rights to the horrible primitive anti-womxn Muslims? Yes indeed, it was. I'm sure glad we got rid of those primitive simian anti-womxns. We wouldn't want any womxns to learn a useful craft. And we certainly wouldn't want a womxn to gain a justified reputation as an astronomer and instrument-maker. All womxns must spend all their time drinking to blackout, shouting incoherent Correct Slogans, and beating up peasants, following in the staggering footsteps of Our Most Noble Goddess Hillary. = = = = = Now back to the astrolabe itself. A typical astrolabe has a static mater (the outer ring) containing a separate and removable plate, the inner map. The plate could be switched out for use in different locations, or to provide a different set of curves and functions for the movable parts. The mater corresponds to the base containing A and D scales on a linear slide rule. The part that looks like a horse was called the horse for mysterious reasons. Descriptions are unclear on its function; maybe it was a cotterpin to hold the movable parts.
The starmap pointer is the rete (net), including specific labeled extensions for major stars. The upper circular part is used in calculations, and can be turned independently on some versions. The rete corresponds to the slider (B and C scales) on a slide rule.
On top of the rete is the rule, corresponding to the cursor on a slide rule.
The unique part is the alhidade, on the back. As with the big instruments, you sight through the pinholes to determine height of a star or sun. You could also lay the astrolabe flat on a table or pillar, line up with north, and use the alhidade to sight an azimuth.
= = = = =
Jumping from 800AD to right now:
I bought an astrolabe kit from Dreipunkt in Germany. They make a variety of kits and learning toys. The kit is an interesting mix of old materials and new methods. It's entirely made of wood. Even the axle and joining pegs are wood. The wood comes in a hi-tech form, three VERY thin laminated layers, and the pieces are cut by lasers. I built it in one hour with no errors, despite my complete lack of wood skill. No tools or glue needed, except for some careful hammering of the joining pegs. Dreipunkt must have done some heavy Murphy testing on their instructions if even a wood-idiot like me can get it right!
Real astrolabes were kit-like. The horse cotterpin allowed you to remove any of the pieces, or switch the starmap plate to different maps or latitudes. Dreipunkt custom-printed a starmap for my location, labeled Spokane!
Back side with alhidade:
Front with rete:
Blurry closeup of the location:
I tried following the directions to determine the time of day, which isn't really useful now but would have been routine in 800 AD before clockwork.
I used the Alhidade to measure the height of the sun over the horizon, sighting through the two pinholes. 18 degrees above horizon.
Then I re-used the Alhidade to locate the 'starsign date' from today's date. June 6 = Gemini + 16 degrees.
Then I turned the Rete to line up Gemini+16 with the great circle for 18 degrees on the Plate. 18 is between 10 and 20, with no finer lines, so this didn't feel very accurate.
Then I turned the Rule to the same Gemini+16 on the Rete, and read off the time on the Mater. Appeared to be about 6:05. The clock time when I sighted the sun was 6:13 standard time, so this isn't too bad for a first try! (Later, used an online calculator to get solar time from standard time, and the astrolabe is about 15 minutes from solar time.)
= = = = =
Astrolabes should have spawned circular slide rules but for some reason they didn't. The linear slide rule developed from Napier's Bones, and the circular slide rule or wheel chart developed much later. None of those rules included the measurement tool, so astrolabes (and their descendants like sextants) are still unique.
= = = = =
Later footnote: Yes, the horse was a cotterpin.
This duty would be originally discharged by a pin with a large head at one end, and a slot at the other through which a cotteril or wedge passed to hold it in place; this wedge is sometimes made into the shape of a horse, and is so called.
Labels: Entertainment, Equipoise, Metrology, Natural law = Sharia law, new toy
¶ 9:12 AM
Thursday, September 24, 2020
Real Coherers!
After doing an emotional salute to the coherer, I got curious to see if any original coherers were available, or a newly made version. No originals, but amazingly Navone Engineering is making new ones following the original Marconi recipe.
We'll do the unboxing routine. In the box:
The packed innards:
And here's the coherer, along with a penny for scale and a submini tube for comparison. (The powder is in the short gap between the two brass rods.)
The actual coherer looks better up close than Navone's promo pic on Ebay. It's made the same way as the submini tubes that I was playing with a few years ago.
The enclosed instruction brochure is well written, professionally printed and folded. It runs through the same history I covered, including the Japanese 'second life' of coherers.
Navone included a little piezo sparker to make a proper electric spark. This was actually the hardest part of the experiment for me. I understand coherers but I'd never used a sparker, and various online videos didn't clarify how to use them. The button was too firm for my elderly fingers. I used Channellocks to squeeze it until it SNAPPED, and got a spark.
I set up a simple series circuit on my homemade lab breadboard. After trying various combos of voltage and LEDs and meters and resistors, I ended up using 3V with no inline resistor and a little incandescent bulb.
The coherer is highly sensitive to tapping, as it should be; and it's also highly sensitive to the applied potential difference. When powered by 9 or 18 Volts, it wants to conduct all the time. On 1.5 V it doesn't want to conduct at all. 3V is the Mama Bear.
Very low light before the spark, light increases after the spark, and stays on until tapped.
Here's a GIF showing one sequence of spark on / tap off.
= = = = =
And here's a schematic version.
= = = = =
Happy second life, Coherers!
Techy footnote: Coherers weren't originally meant to sense nearby sparks and RF in the ether; they were meant to sense RF in the circuit from an antenna input. They worked both ways.
This real coherer doesn't seem to respond to non-sparky RF. I tried keying my little Pixie 40-meter transmitter near it, and even touched the antenna wire from the Pixie to the coherer's wire. No brightening. It does respond to a mechanically generated spark from my flint propane lighter.
The packed innards:
And here's the coherer, along with a penny for scale and a submini tube for comparison. (The powder is in the short gap between the two brass rods.)
The actual coherer looks better up close than Navone's promo pic on Ebay. It's made the same way as the submini tubes that I was playing with a few years ago.
The enclosed instruction brochure is well written, professionally printed and folded. It runs through the same history I covered, including the Japanese 'second life' of coherers.
Navone included a little piezo sparker to make a proper electric spark. This was actually the hardest part of the experiment for me. I understand coherers but I'd never used a sparker, and various online videos didn't clarify how to use them. The button was too firm for my elderly fingers. I used Channellocks to squeeze it until it SNAPPED, and got a spark.
I set up a simple series circuit on my homemade lab breadboard. After trying various combos of voltage and LEDs and meters and resistors, I ended up using 3V with no inline resistor and a little incandescent bulb.
The coherer is highly sensitive to tapping, as it should be; and it's also highly sensitive to the applied potential difference. When powered by 9 or 18 Volts, it wants to conduct all the time. On 1.5 V it doesn't want to conduct at all. 3V is the Mama Bear.
Very low light before the spark, light increases after the spark, and stays on until tapped.
Here's a GIF showing one sequence of spark on / tap off.
= = = = =
And here's a schematic version.
= = = = =
Happy second life, Coherers!
Techy footnote: Coherers weren't originally meant to sense nearby sparks and RF in the ether; they were meant to sense RF in the circuit from an antenna input. They worked both ways.
This real coherer doesn't seem to respond to non-sparky RF. I tried keying my little Pixie 40-meter transmitter near it, and even touched the antenna wire from the Pixie to the coherer's wire. No brightening. It does respond to a mechanically generated spark from my flint propane lighter.
Labels: Carver, Equipoise, new toy, Trinity House
¶ 10:00 AM
Friday, May 08, 2020
Elgin postscript
When I get attached to a 'patient' company, I like to put some money on the line. Pay for value, equipoise. In the case of Elgin, the company went out of business in 1970, so the only choice is an old product.
When I buy a new toy, I prefer something useful, generally something that will help me function independently in power outages or other off-grid situations.
For Elgin, the two purposes intersected at this Ebay item.
Pic with my awful camera in the usual place just to prove it's really here:
Pic from the seller who had a real camera:
A wind-up travel clock is useful off-grid, and my existing battery-powered clock failed in the last outage. Wind-up is better than battery anyway because batteries run down. (I'll run down sooner or later, but if I'm alive enough to need a clock or a shaver, I'll be alive enough to wind them up.)
This clock is in mint condition, ticks and keeps time, alarm rings. It has an extra feature that attracted extra attention: the variable time-zone circle on the front. It's an Equation clock! Not a very useful gimmick, but a nice connection to the subject at hand.
Religions generally use physical tokens like prayer cloths or rosaries to connect and comfort the believers. I enjoy having physical tokens for my peculiar little Wheatstone religion.
It was made in 1969, just before Elgin went out of business, but unfortunately just after Elgin closed its American factory. It says 'made by Bradley Time division, Japan.' Well, beggars can't be choosers. I might try again later with better knowledge, but this will do for now.
= = = = =
This clock got its first chance to serve in the Jan 2021 windstorm and outage. Loyal service! Thanks, Elgin.
Pic from the seller who had a real camera:
A wind-up travel clock is useful off-grid, and my existing battery-powered clock failed in the last outage. Wind-up is better than battery anyway because batteries run down. (I'll run down sooner or later, but if I'm alive enough to need a clock or a shaver, I'll be alive enough to wind them up.)
This clock is in mint condition, ticks and keeps time, alarm rings. It has an extra feature that attracted extra attention: the variable time-zone circle on the front. It's an Equation clock! Not a very useful gimmick, but a nice connection to the subject at hand.
Religions generally use physical tokens like prayer cloths or rosaries to connect and comfort the believers. I enjoy having physical tokens for my peculiar little Wheatstone religion.
It was made in 1969, just before Elgin went out of business, but unfortunately just after Elgin closed its American factory. It says 'made by Bradley Time division, Japan.' Well, beggars can't be choosers. I might try again later with better knowledge, but this will do for now.
= = = = =
This clock got its first chance to serve in the Jan 2021 windstorm and outage. Loyal service! Thanks, Elgin.
Labels: Equipoise, new toy, Patient things
¶ 12:04 AM
Friday, April 19, 2019
Quick review of Veras 225
Once a year or so I buy a New Toy, usually a Soviet product. This year's toy is a Veras receiver, made in Belarus and sold by an Ebay trader in Belarus.
There's an excellent review of the Veras in Vremax's blog.
I'll echo his comment:
Veras radios made by the Grodno Radio Factory (which is no more, thank you international capitalists) were clones of the famous Soviet-era OKEAN (meaning Ocean) radios.
Belarus has done better than most countries at maintaining its Soviet-era advantages, but globalism always kills you in the end.
I can only add one item he didn't cover.
This is a thoroughly modern receiver, mostly discrete transistors with one IC for the band-selector function. Hitting any band button turns the radio on. The on-off button (white) is effectively only the Off button. Sound is excellent, with separate bass and treble tone controls. Tuning is easy and consistent, and it picks up one or two SW stations, which is as much as I can ask in this location. As I've noted before, Spokane is a dead spot for SW; and my house, next to a power line and clad with aluminum siding, is even deader.
One thing Vremax didn't mention: The two buttons on top are Squelch and AFC. The Squelch button is pressed here. It does seem to cut down on noise between stations. I can't tell if the AFC works because I can't pick up any distant stations that would fade.
The package includes a complete schematic, which is actually more interesting than the radio. On a rough count, it has 40 transistors, 40 regular diodes, and 10 varactor diodes. I've never seen varactors used so heavily.
The power supply section has a simple and elegant trick. When you plug in a 12VDC external supply, it goes in series with the secondary of the 220V input. So the 12 is free to be AC, or DC connected either way. The full-wave rectifier will turn all three possibilities into DC of the correct polarity.
However: This creates an obvious problem. When 12V is connected to the secondary, you can't have anything on the primary. If the mains cord is plugged in, everything will blow up; if not plugged in and the 12V supply is AC, you could get a 220V shock from the mains plug.
This mask plate prevents the problem. You can turn it three ways, for AC or 12V external or battery. You can't reach the 12V plug without removing the 220VAC plug from the radio.
= = = = =
Among all of my toys, the best SW receiver is still this little regen, built from an MFJ kit.
Regen does the best job of rejecting powerline noise and catching the VERY FEW stations that are available here.
= = = = =
Later semi-relevant sidenote: Recently I was feeling illish for a while, so used taxis to get around. One of the taxi drivers was complaining that her AM radio lost volume when she drove into this neighborhood. She had to turn up the volume knob considerably. I suppose her car's electric system could have failed at that moment, but it was a Toyota so that's unlikely.
This is a thoroughly modern receiver, mostly discrete transistors with one IC for the band-selector function. Hitting any band button turns the radio on. The on-off button (white) is effectively only the Off button. Sound is excellent, with separate bass and treble tone controls. Tuning is easy and consistent, and it picks up one or two SW stations, which is as much as I can ask in this location. As I've noted before, Spokane is a dead spot for SW; and my house, next to a power line and clad with aluminum siding, is even deader.
One thing Vremax didn't mention: The two buttons on top are Squelch and AFC. The Squelch button is pressed here. It does seem to cut down on noise between stations. I can't tell if the AFC works because I can't pick up any distant stations that would fade.
The package includes a complete schematic, which is actually more interesting than the radio. On a rough count, it has 40 transistors, 40 regular diodes, and 10 varactor diodes. I've never seen varactors used so heavily.
The power supply section has a simple and elegant trick. When you plug in a 12VDC external supply, it goes in series with the secondary of the 220V input. So the 12 is free to be AC, or DC connected either way. The full-wave rectifier will turn all three possibilities into DC of the correct polarity.
However: This creates an obvious problem. When 12V is connected to the secondary, you can't have anything on the primary. If the mains cord is plugged in, everything will blow up; if not plugged in and the 12V supply is AC, you could get a 220V shock from the mains plug.
This mask plate prevents the problem. You can turn it three ways, for AC or 12V external or battery. You can't reach the 12V plug without removing the 220VAC plug from the radio.
= = = = =
Among all of my toys, the best SW receiver is still this little regen, built from an MFJ kit.
Regen does the best job of rejecting powerline noise and catching the VERY FEW stations that are available here.
= = = = =
Later semi-relevant sidenote: Recently I was feeling illish for a while, so used taxis to get around. One of the taxi drivers was complaining that her AM radio lost volume when she drove into this neighborhood. She had to turn up the volume knob considerably. I suppose her car's electric system could have failed at that moment, but it was a Toyota so that's unlikely.
Labels: Natural law = Soviet law, new toy
¶ 1:52 AM
Tuesday, February 26, 2019
Fun with Soviet maps
Via ZH, the Russian internal TV channel showed several targets. Supposedly these are Presidential hideouts. Camp David is obvious, but the one in this area wasn't familiar. It's Jim Creek Naval Communications station, way out in the Cascades.
Googlemaps shows it at Lat 48.213, Long -121.949. It's east and a little north of Arlington, north of Robe, and south of the midway point between Oso and Hazel.
The Soviet map for this zone isn't as fine as some of the maps I was using before. I've circled the general area using the cities as landmarks. There are no points of interest anywhere in the vicinity.
These maps showed plenty of military sites, including obsolete airfields. If this location had been interesting to the Soviets in 1980, it would have been on the map.
What's REALLY interesting is the identification of Jim Creek as a hideaway. AFAIK it hasn't been mentioned before in Western media.
These maps showed plenty of military sites, including obsolete airfields. If this location had been interesting to the Soviets in 1980, it would have been on the map.
What's REALLY interesting is the identification of Jim Creek as a hideaway. AFAIK it hasn't been mentioned before in Western media.
Labels: new toy
¶ 8:09 AM
Thursday, October 27, 2016
What are you paying for?
Still feeling somewhat guilty for using Brüel & Kjær when I could have pushed for GenRad, I decided to make a small votive offering to the Made In USA gods, who are also the analog gods. Found a GenRad sound level meter on Ebay from a vendor in Kansas, bought it for $50.
This one is about 20 years old. It was used by the Kansas Dept of Transportation, probably for highway noise abatement studies. Note the calibration sticker from 2004. Presumably the Ebay vendor bought it at a state gov't surplus auction.
SLMs aren't especially exciting or complicated. I bought a similar-looking Chinese unit from Radio Shack back in the '90s for the same $50. New Chinese SLMs of similar specs are still in the $50 range.
This GenRad unit is higher quality than the Radio Shack SLM. Claims to be made in USA. Satisfyingly hefty and still working perfectly. The pouch is real leather. Based on those differences, I guessed the price of a new unit should be around $300.
What's the actual GenRad price?
THREE THOUSAND DOLLARS? YOW!
What are you paying for?
Simple answer: Legal authority. Chain of evidence. Bully power. When you buy new from GR and maintain calibration through GR, you can use the readings in court. That's why the Kansas DOT buys from GR instead of using cheap Chinese meters. They have to be prepared to defend all of their decisions against a Soros-powered environmental group, or against a JPMorgan-powered corporation. Noise readings are a minor part of those defenses, but even noise readings have to stand up in court.
Direct parallel to medical costs. When a doctor tells you to buy a Mylan EpiPen for $700, the doctor is comparatively safe because Mylan has performed all the FDA nonsense. If the doc told you to buy an equivalent EpiPen through Craigslist for $10, he wouldn't be safe from lawyers.
This is the dominant form of 'economic rent' in USA STRONG. It's a Tribal protection racket, indistinguishable from the older Italian version. Syndicate creates a threat, then charges citizens to avoid the threat.
Well, there is one difference. The Tribal syndicate has an iron grip on all levels of government, while the Italian syndicate was only able to buy some parts of some city governments. So there's no Bunco Squad available to counteract this racket.
= = = = =
June 2020 footnote: I finally made this SLM useful. I don't really need to take noise readings. I bought it partly as gratitude to GenRad, and partly for the sound output, thinking it would serve as a microphone. At first I couldn't make the output work, so I assumed it was broken, or maybe it wasn't really meant to be a sound output. The SLM stayed on the shelf for 4 years. Finally this year I got bored enough to try it again with different plugs and cables. The jack is a 'micro' size, and it's recessed behind a D-shaped plastic hole, so most plugs can't get in. I suspect it was meant to take a proprietary GenRad plug, like the similarly official Webster Chicago wire recorder. After I found the right narrow-handled plug, the SLM turns out to be a splendid microphone, putting out lots of voltage to satisfy the computer's input. No hum or hiss, and the weighting buttons filter the sound in different ways. Rediscovering or rejuvenating a forgotten item is one of life's outstanding pleasures.
= = = = =
July 2020: Now I'm using it for noise readings after all.
This one is about 20 years old. It was used by the Kansas Dept of Transportation, probably for highway noise abatement studies. Note the calibration sticker from 2004. Presumably the Ebay vendor bought it at a state gov't surplus auction.
SLMs aren't especially exciting or complicated. I bought a similar-looking Chinese unit from Radio Shack back in the '90s for the same $50. New Chinese SLMs of similar specs are still in the $50 range.
This GenRad unit is higher quality than the Radio Shack SLM. Claims to be made in USA. Satisfyingly hefty and still working perfectly. The pouch is real leather. Based on those differences, I guessed the price of a new unit should be around $300.
What's the actual GenRad price?
THREE THOUSAND DOLLARS? YOW!
What are you paying for?
Simple answer: Legal authority. Chain of evidence. Bully power. When you buy new from GR and maintain calibration through GR, you can use the readings in court. That's why the Kansas DOT buys from GR instead of using cheap Chinese meters. They have to be prepared to defend all of their decisions against a Soros-powered environmental group, or against a JPMorgan-powered corporation. Noise readings are a minor part of those defenses, but even noise readings have to stand up in court.
Direct parallel to medical costs. When a doctor tells you to buy a Mylan EpiPen for $700, the doctor is comparatively safe because Mylan has performed all the FDA nonsense. If the doc told you to buy an equivalent EpiPen through Craigslist for $10, he wouldn't be safe from lawyers.
This is the dominant form of 'economic rent' in USA STRONG. It's a Tribal protection racket, indistinguishable from the older Italian version. Syndicate creates a threat, then charges citizens to avoid the threat.
Well, there is one difference. The Tribal syndicate has an iron grip on all levels of government, while the Italian syndicate was only able to buy some parts of some city governments. So there's no Bunco Squad available to counteract this racket.
= = = = =
June 2020 footnote: I finally made this SLM useful. I don't really need to take noise readings. I bought it partly as gratitude to GenRad, and partly for the sound output, thinking it would serve as a microphone. At first I couldn't make the output work, so I assumed it was broken, or maybe it wasn't really meant to be a sound output. The SLM stayed on the shelf for 4 years. Finally this year I got bored enough to try it again with different plugs and cables. The jack is a 'micro' size, and it's recessed behind a D-shaped plastic hole, so most plugs can't get in. I suspect it was meant to take a proprietary GenRad plug, like the similarly official Webster Chicago wire recorder. After I found the right narrow-handled plug, the SLM turns out to be a splendid microphone, putting out lots of voltage to satisfy the computer's input. No hum or hiss, and the weighting buttons filter the sound in different ways. Rediscovering or rejuvenating a forgotten item is one of life's outstanding pleasures.
= = = = =
July 2020: Now I'm using it for noise readings after all.Labels: Age of Stings, Metrology, new toy
¶ 5:42 PM
Thursday, June 09, 2016
More fun with tubes
Experimenting with the Mystery Tube inspired me to dig further into submini tubes. I'd skipped tubes in my previous electronics playing. Big tubes require way too much overhead. Multi-winding transformers and rectifiers; sheetmetal work to hold the sockets; worst of all, the whole setup, including the experimenter, needs to be ready to handle 250V. Amid all that expense and danger there's not much room for piddling around.
These subminis are no worse than transistors in terms of overhead, and far more interesting than transistors.
I ordered a bunch of hearing aid tubes through Ebay, type 6418 pentodes.
The 5-packs seem to have been assembled by a previous big retailer in 1985, who also added a UPC code to the tube boxes.
Here's one tube along with its original milspec box. The code starting with 5960 is the military part number. Looking it up, this particular number is no longer used, but there are still a LOT of active 5960 (tube) numbers. Smart military, holding onto EMP-immune technology as long as possible. Not nearly as smart as Russia, but that doesn't need saying. [Sidenote: WW2-era milspec tube boxes said TUBE, ELECTRON, ONE instead of ONE EACH ELECTRON TUBE. Old way was funnier.]
Tube along with the two transistors that would be needed to replace it. Some applications would need three.
Sidenote: When these tubes were used in hearing aids, the wires were soldered to a little inline 5-pin plug, which was inserted in a socket on the chassis. Made replacement easier. I thought this was how the tubes were sold, but after looking at a lot of them on Ebay, I'm only seeing raw wires. Puzzling. Maybe hearing aid companies like Zenith added the sockets so the hearing aid salesman could replace tubes easily.
The Ebay price was $14 for 20 tubes in NOS condition. 70 cents each! Outstanding bargain. 20 tubes should allow for some bad units, give me a chance to burn up a few.
In general Ebay tube prices are well below what specialist 'antique electronics' dealers charged 10 years ago. Tubes prized by audiophiles (such as matched Mullard long-plate ECC83s) run into the hundreds, but most are close to their original price in nominal dollars, not inflated dollars.
I'm guessing this tube was made in the late '50s. A few common tubes were around a dollar in 1959, but most were around $3.00 retail, and this submini is in the typical range. A page from an Allied catalog in 1959 includes the 6418 (circled):
$3.05 would be $25 now by plain inflation.
Incidentally, the tube at the bottom of the page, priced at $5300!! ($44k today) was a high-power water-cooled UHF Klystron transmitting tube. It probably would have been used by a military radar installation, and wouldn't have been bought through Allied.
= = = = =
Starting to play around. Hooked up 1.5v to filament. It lights! Yay! The light and heat are delicate compared to a larger tube; this isn't going to emit tube glow or tube smell. Even with all the room lights off, it's just barely visible, and just barely warm.
Tried using a rechargeable weedwhacker battery for 20V plate. Because the big batt has nearly unlimited 'push', it turned out to be almost as dangerous as the AC mains. I had to use clip leads to connect to it. When both clip leads accidentally touched the aluminum foil surface of my workdesk, BZZZT! Arc welding! Big noise, big spark, hole in the foil, smoke in the wood.
Decided to fall back to tame 9V batt, already part of my breadboard setup. The tube's data sheet claims that the tube should still amplify with 9V, though it's near the low end of working range.
= = = = =
Next day: Yay! Amplifier action! Contrary to the data sheet, 9V wasn't enough. Had to put two nines in series to get a tame 18V plate supply. With the extra pull, a simple ckt worked just the way it should. Here's the ckt, scrawled and scanned:
The voltmeter is across the plate resistor, so a higher reading means more flow through the cathode and plate. Screen grid is tied to plus through the same size R. Suppressor grid is internally tied to filament. The control grid is highly sensitive; touching with fingers changes the flow, and 'bridging' to other wires with fingers makes more flow.
Short clip showing the action:
Now that I've got my literal hands on the basic requirements, I can move on to more interesting stuff. More later.......
The 5-packs seem to have been assembled by a previous big retailer in 1985, who also added a UPC code to the tube boxes.
Here's one tube along with its original milspec box. The code starting with 5960 is the military part number. Looking it up, this particular number is no longer used, but there are still a LOT of active 5960 (tube) numbers. Smart military, holding onto EMP-immune technology as long as possible. Not nearly as smart as Russia, but that doesn't need saying. [Sidenote: WW2-era milspec tube boxes said TUBE, ELECTRON, ONE instead of ONE EACH ELECTRON TUBE. Old way was funnier.]
Tube along with the two transistors that would be needed to replace it. Some applications would need three.
Sidenote: When these tubes were used in hearing aids, the wires were soldered to a little inline 5-pin plug, which was inserted in a socket on the chassis. Made replacement easier. I thought this was how the tubes were sold, but after looking at a lot of them on Ebay, I'm only seeing raw wires. Puzzling. Maybe hearing aid companies like Zenith added the sockets so the hearing aid salesman could replace tubes easily.
The Ebay price was $14 for 20 tubes in NOS condition. 70 cents each! Outstanding bargain. 20 tubes should allow for some bad units, give me a chance to burn up a few.
In general Ebay tube prices are well below what specialist 'antique electronics' dealers charged 10 years ago. Tubes prized by audiophiles (such as matched Mullard long-plate ECC83s) run into the hundreds, but most are close to their original price in nominal dollars, not inflated dollars.
I'm guessing this tube was made in the late '50s. A few common tubes were around a dollar in 1959, but most were around $3.00 retail, and this submini is in the typical range. A page from an Allied catalog in 1959 includes the 6418 (circled):
$3.05 would be $25 now by plain inflation.
Incidentally, the tube at the bottom of the page, priced at $5300!! ($44k today) was a high-power water-cooled UHF Klystron transmitting tube. It probably would have been used by a military radar installation, and wouldn't have been bought through Allied.
= = = = =
Starting to play around. Hooked up 1.5v to filament. It lights! Yay! The light and heat are delicate compared to a larger tube; this isn't going to emit tube glow or tube smell. Even with all the room lights off, it's just barely visible, and just barely warm.
Tried using a rechargeable weedwhacker battery for 20V plate. Because the big batt has nearly unlimited 'push', it turned out to be almost as dangerous as the AC mains. I had to use clip leads to connect to it. When both clip leads accidentally touched the aluminum foil surface of my workdesk, BZZZT! Arc welding! Big noise, big spark, hole in the foil, smoke in the wood.
Decided to fall back to tame 9V batt, already part of my breadboard setup. The tube's data sheet claims that the tube should still amplify with 9V, though it's near the low end of working range.
= = = = =
Next day: Yay! Amplifier action! Contrary to the data sheet, 9V wasn't enough. Had to put two nines in series to get a tame 18V plate supply. With the extra pull, a simple ckt worked just the way it should. Here's the ckt, scrawled and scanned:
The voltmeter is across the plate resistor, so a higher reading means more flow through the cathode and plate. Screen grid is tied to plus through the same size R. Suppressor grid is internally tied to filament. The control grid is highly sensitive; touching with fingers changes the flow, and 'bridging' to other wires with fingers makes more flow.
Short clip showing the action:
Now that I've got my literal hands on the basic requirements, I can move on to more interesting stuff. More later.......
Labels: defensible thymes, new toy, skill-estate, Zero Problems
¶ 11:13 AM
Saturday, May 28, 2016
Experimental non-transistor
I was idly browsing Ebay for Soviet transistors. Curious to see if the oldest ones looked similar to America's oldest transistors. Mostly yes. The Prince Albert shape of the early ones reminded me of my first live encounter with a transistor.....
Around 1958 I was fiddling with radios and electric stuff, and somehow picked up a catalog from Burstein Applebee. Spent hours dreaming through it. When parents visited an uncle in KC, I badgered them into letting me see the Burstein Applebee store in downtown KCMO. They dropped me off and went shopping somewhere else. I walked in and started wandering the aisles, marveling at all the receivers and antennas and tubes. The clerks were NOT happy to have an 8-year-old loose in the store. They herded me out, but not before I got a good look at THE REAL THING: A Raytheon CK722.
Does Ebay have CK722s? Plenty of them but that wasn't the most interesting item. Seller VintChip had a Raytheon 'experimental transistor' for $50.
Instant choice. Had to buy it.
Unpacking......
Vintchip does a good job of packing. Bubble wrap and tissue.
First impression: Printed label says Raytheon Experimental. Written in ink on one side is QF336, on the other side just the number 8. Presumption: This is serial number 8 of a set of experimental tubes denominated QF336.
Scanned both sides:
Looks very much like a miniature hearing-aid tube. Same glass outer envelope, same leads coming through the bottom sealed in glass, same 'can' surrounding the active part. Mini tubes were used in hearing aids briefly in the '50s. Hearing aids soon switched to transistors, but not because of size. Early transistors were about half the size of mini tubes and you needed two or three transistors to substitute for the typical tube. No real advantage. Batteries were the advantage. Tubes needed a large 1.5V filament batt and a large 45V plate batt, and used up the filament batt fast. Transistors used one 9V battery and drained it slowly.
= = = = =
I can see the innards with a magnifier, but couldn't get a photo or scan. So I made a Poser version to illustrate. Two cylinders running through the can in parallel; one cylinder has one wire from it, and the other cylinder has a sort of sheath, with one wire centered and another wire Y-ing out of the sheath.
Innards STRONGLY suggest tube. The sheathed electrode is typical of a cathode with inner heater, with one side of heater tied to cathode. The opposite cylinder looks like the plate. Thinking tubey, this webpage shows a Sylvania experimental miniature thyratron, looking something like qf336, but the Sylvania has four terminals, which seems right. This critter has only three wires, which means it can't be a triode or a thyratron. Could it be a rectifier or a voltage-dependent switch?
One problem with tube assumption: the upper and lower ends of the can are closed by resin or epoxy. Tubes generally get too hot for epoxy.
Thinking solid-statey, the wire pattern reminds me of a thyristor or SCR schematic. Does this mean the schematic was meant to imitate this device? Probably not.
Well, let's try both assumptions. Using DVM, no connectedness shows between the terminals. On R scale and diode scale, just open ckt in both directions on all combinations of the three wires. About 7nF capacitance between terminals, which makes sense from the structure but doesn't mean anything. So this probably isn't solid-state, because even a blown or non-functional solid thing will show some kind of resistance.
I don't have any proper mini tubes for comparison. A large tube (35L6) shows about 40Ω across the filament, varying as the applied voltage slightly warms the heater. I don't know what to expect for a mini tube, but it would certainly be low enough to read easily. Two-digit ohms, not gonna look like open ckt.
= = = = =
Just for fun, trying the tube assumption in the simplest possible ckt for a rectifier. Battery across the filament, cathode to negative, 9V to the plate through a resistor, with voltmeter across the resistor to see if anything flows.
Nope. No heat from the filament, no flow at all.
Conclusion: This is probably a diode tube, and the filament is probably burned out.
= = = = =
Well. Was this $50 worth of fun? Yes! I got to handle a little piece of history, got to solve a little mystery. Whatever this thing is, it's NOT solid state. Most likely a rectifier tube, perhaps with gas that glows or provides a sudden discharge for a 'fuse'.
More importantly, this gives me an idea for some old-fashioned messing around. I never experimented with normal-size tubes because they require multiple high voltages and serious sheetmetal work. Way too much danger and 'overhead' for experimenting. These mini tubes can be run on batteries and can be popped into a regular breadboard. Many of them take 22.5V plate, which I can grab conveniently and safely from the rechargeable batt for my weed-whacker.
= = = = =
Next fun here.
Vintchip does a good job of packing. Bubble wrap and tissue.
First impression: Printed label says Raytheon Experimental. Written in ink on one side is QF336, on the other side just the number 8. Presumption: This is serial number 8 of a set of experimental tubes denominated QF336.
Scanned both sides:
Looks very much like a miniature hearing-aid tube. Same glass outer envelope, same leads coming through the bottom sealed in glass, same 'can' surrounding the active part. Mini tubes were used in hearing aids briefly in the '50s. Hearing aids soon switched to transistors, but not because of size. Early transistors were about half the size of mini tubes and you needed two or three transistors to substitute for the typical tube. No real advantage. Batteries were the advantage. Tubes needed a large 1.5V filament batt and a large 45V plate batt, and used up the filament batt fast. Transistors used one 9V battery and drained it slowly.
= = = = =
I can see the innards with a magnifier, but couldn't get a photo or scan. So I made a Poser version to illustrate. Two cylinders running through the can in parallel; one cylinder has one wire from it, and the other cylinder has a sort of sheath, with one wire centered and another wire Y-ing out of the sheath.
Innards STRONGLY suggest tube. The sheathed electrode is typical of a cathode with inner heater, with one side of heater tied to cathode. The opposite cylinder looks like the plate. Thinking tubey, this webpage shows a Sylvania experimental miniature thyratron, looking something like qf336, but the Sylvania has four terminals, which seems right. This critter has only three wires, which means it can't be a triode or a thyratron. Could it be a rectifier or a voltage-dependent switch?
One problem with tube assumption: the upper and lower ends of the can are closed by resin or epoxy. Tubes generally get too hot for epoxy.
Thinking solid-statey, the wire pattern reminds me of a thyristor or SCR schematic. Does this mean the schematic was meant to imitate this device? Probably not.
Well, let's try both assumptions. Using DVM, no connectedness shows between the terminals. On R scale and diode scale, just open ckt in both directions on all combinations of the three wires. About 7nF capacitance between terminals, which makes sense from the structure but doesn't mean anything. So this probably isn't solid-state, because even a blown or non-functional solid thing will show some kind of resistance.
I don't have any proper mini tubes for comparison. A large tube (35L6) shows about 40Ω across the filament, varying as the applied voltage slightly warms the heater. I don't know what to expect for a mini tube, but it would certainly be low enough to read easily. Two-digit ohms, not gonna look like open ckt.
= = = = =
Just for fun, trying the tube assumption in the simplest possible ckt for a rectifier. Battery across the filament, cathode to negative, 9V to the plate through a resistor, with voltmeter across the resistor to see if anything flows.
Nope. No heat from the filament, no flow at all.
Conclusion: This is probably a diode tube, and the filament is probably burned out.
= = = = =
Well. Was this $50 worth of fun? Yes! I got to handle a little piece of history, got to solve a little mystery. Whatever this thing is, it's NOT solid state. Most likely a rectifier tube, perhaps with gas that glows or provides a sudden discharge for a 'fuse'.
More importantly, this gives me an idea for some old-fashioned messing around. I never experimented with normal-size tubes because they require multiple high voltages and serious sheetmetal work. Way too much danger and 'overhead' for experimenting. These mini tubes can be run on batteries and can be popped into a regular breadboard. Many of them take 22.5V plate, which I can grab conveniently and safely from the rechargeable batt for my weed-whacker.
= = = = =
Next fun here.Labels: defensible spaces, new toy, TMI
¶ 10:48 AM
