Beauty of old electrical and measuring things, etc.

[dlgoff]

They're interesting also from a mechanical perspective.
The front and back vibrate in various modes, not just as a simple sheet
a wood soundpost about the diameter of a pencil is placed right underneath the 'bridge' to mechanically couple couple them,
and a 'bass bar' stiffens the front to help it produce low notes,
as you can imagine the varying thickness of those front and back plates controls the sound of the fiddle.
Yours was well made. The neck mount was unusual, similar to that of a region in the way northeast of Germany. Harry liked its tone and said whoever thinned its front and back knew what he was doing..

Theory of vibrating plates is an interesting nichesee also
http://newt.phys.unsw.edu.au/jw/violintro.htmlhttp://newt.phys.unsw.edu.au/jw/chladni.html
I hope your grandchildren enjoy it as much as you did..

Thanks for these references Jim. And thank Harry for his expert restoration.
I hope this fiddle will be passed down for generations.

 

[davenn]

Hi Don,

Had to show you this old bit of gear I found in a historical society museum in the city of Bathurst, NSW Australia.
Wife and I had a long weekend holiday there a couple of weekend's ago

Dating from the early 1900's, an X-ray "machine"

No shielding or anything, just "spray and pray" hahahaDave

 

[dlgoff]

Hi Don,

Had to show you this old bit of gear I found in a historical society museum in the city of Bathurst, NSW Australia.
Wife and I had a long weekend holiday there a couple of weekend's ago

Dating from the early 1900's, an X-ray "machine"

View attachment 245251

View attachment 245252

No shielding or anything, just "spray and pray" hahahaDave

That is so awesome @davenn. I'd love to be "spraying" some X-rays with it. Would go good with my other "spray" machine.

 

[Mark44]

sorry ths one's off topic, being not electrical..

Just put a pickup in it, making it an electric violin.

 

[dlgoff]

Just put a pickup in it, making it an electric violin.

Just like my old friend Robby Steinhardt did.

 

[davenn]

Just like my old friend Robby Steinhardt did.

don't know him

 

[dlgoff]

don't know him

He played in the band Kansas.

 

[dlgoff]

I was recently given this Radio Shack (Realistic) PRO-77A VHF HI-LO SCANNER. The easiest part of this restoration was giving it a new black "hammer toned" finish. The hardest part was finding and replacing one of the channel lamps. The only one I could come up with that would fit the front panel's lamp hole was rated for 3 Volts DC and the scanner's lamp supply was 14 Volts DC. So after a little trial and error I found a resistor, when in series with the lamp, emitted the right intensity (brightness). Here's the finished receiver:
(Edit: According to https://www.radiomuseum.org/, it was manufactured in 1978 ??)

Also, here's an old Johnson Duo-Scan receiver I've had for a while. Just needed a good cleaning.

 

[jim hardy]

Just put a pickup in it, making it an electric violin.

Sounds incongruous at first.
But - why not ? It'd make for interesting experiments.
A tiny accelerometer right under the bridge perhaps...
I guess it's no more outlandish than my kids' Bluetooth turntable

wow, i thought his was startling enough...

Roll Over, Beethoven !

old jim

 

[Avaro667]

Even as a kid, I saw beauty in old devices. That made me want to understand how they worked. I had lots of old things that I keep and now reviving. Old things need to work to see the beauty. Here's what I've done so far.

Two views of the gadgets shelves and my small work space:

View attachment 134695

View attachment 134696

Here's a close up look at the meters, gauges and other measuring things:

View attachment 134697

This is what I think of as surface-mount electrical components and wiring. The components are very old and shows how electrical wiring was done from ~1915 to ~1930+. The ceramic "stand-offs" were called knobs and ceramic "through-hole" insulators (usually through wood beams) were called tubes. Hence the name, knob and tube wiring. I haven't acquired any tubes however.

View attachment 134698

Everything has been wired to power (with the exception of the knife switch w/fuses with vintage incoming and outgoing cloth insulated wire). The toggle switch is made of black ceramic and brass. The bluish color bulb is very old and still works. The other white bulb is modern, but the pull-chain socket is vintage.

View attachment 134699

View attachment 134700

Here's two reproduction Edison bulbs in vintage ceramic sockets and is switched by the right push-button switches (other push-button is a spare). The switch cover is brass plated copper.

View attachment 134701

These ceramic sockets have pull-chain switches in their bases. The switches still work and the pull chains are original. The clearance between the pull-chain and rotating brass contacts is very small. That's probably why the left pull-chain has an insulator in it.

There's another push-button switch and duplex receptacle in the wall under the surface stuff. It's receptacle and cover are made of Bakelite. That push-button turns on these bulbs:

View attachment 134702

Two of the bulbs are really old; one uses neon to make a flickering flame and one uses phosphorescent purple and green flowers and leaves. They’re running on 115 volt power. The other ones (note the big 1000 watt bulb) filaments are being lighted by 25 volts via a step down transformer so as to just glow and not overwhelm the gas bulbs. The gas bulbs are screwed into vintage ceramic sockets.

There are three high voltage transformers (two are really old). The 6.0 kV transformer powers the green neon tube. Check out how it illuminates my old glassware.

View attachment 134703

The 7.5 kV transformer applies its potential to one end of small vintage fluorescent tubes inserted in the test-tube & distilling flask and causes them to glow from "static" discharge. Note how I tried to make the flask appear to be condensing drops of light from the string of very small neon tubes inside the flask's discharge tube. I was very lucky to find the drip shaped neon tube. I took it out of an old Heath-Kit fish/depth finder.

View attachment 134704

The 9.0 kV transformer power is applied to handmade electrodes. I had two really old bi-metal temperature switches where I removed and reshaped the bi-metal, added the brass "arc tips", and attached them to a vintage glass power line pole insulator. After being power, the bi-metal leads are orientated such that the heat from the current causes the gag to increase; making the arc get longer and longer.

View attachment 134705

This is still a work in progress as I still have to add a brass platted duplex receptacle to supply power to the oscilloscope and sweep generator (just left of the scope) shown in the first photo.

If you have any thing old and would like to share a photo, please do. It's all beautiful in my mind.

Most of these are way older than i am .
Your collection is really nice & quite inspiring,you should be proud of it. It indeed looks very beautiful !

 

[dlgoff]

Your collection is really nice & quite inspiring,you should be proud of it.

Thank you. I'm happy you've taken a look at my goodies.

 

[dlgoff]

I came across this Solarcon Imax 2000 antenna that was really made for the 10 meter Ham Radio Band but can be tuned for 11 meter Citizen Band radio. It's a 5/8 wave vertical antenna; maybe @berkeman can explain how a 5/8 wave antenna works. From what I've been able to find, a 5/8 wave antenna provides a smaller angle (from horizon) of emission than the 1/4 and 1/2 wave antennas; making it good for "DXing". Here's a review of this antenna from CBRadioMagazine.com. It's 24 feet in length; the one on the left.

I'm using it on my Kris 23+ CB:

 

[dlgoff]

Here's a couple OLD beauties I recently acquired:

A GE NE40 neon flicker lamp (manufactured by General Electric)

and a CE 26-C photocell (manufactured by the Continental Electric Co.)

I put the GE NE40 in series with my other flicker lamps that are coupled to the electric field of a plasma globe.

I used a Benjamin tube socket to make a base to display the CE 26-C.

 

[Charlie Cheap]

When I was in radio school in Dallas, tubes were being phased out for transistors (1969) then circuit boards, then IC's. I got out in 1988 when I realized TV repair was going out due to cheap TV's from off-shore and basically being perfected. My son-in-law plays guitar and told me many of them are going back to TUBE amps for their clarity. When he asked why are they so good, I just guessed and said, Maybe amplifying a signal through a solid device is not as CLEAN as amplifying it through a vacuum. Anyway, a lot of musicians are hunting old tube amps.

 

[dlgoff]

My son-in-law plays guitar and told me many of them are going back to TUBE amps for their clarity.

From https://audiophilereview.com/tubes.html

Vacuum tubes are the most sexy, elusive and magical element of all of high end audio. The glowing tube, the single ended tube - it's enough to make an audiophile cry with tears of joy. Maybe tubes aren't as powerful or as accurate as solid state designs but there is just something thrilling about tubes that can't be beat.

 

[Baluncore]

Given a vacuum tube used in an audio amplifier, a semiconductor equivalent can be generated based on FET technology, that meets the same specs, but with more consistent performance, higher power capability and greater efficiency. A tube is just a FETs with a pilot lamp. But:
It is our atavistic need for warmth, and our primitive love of fire, that attracts us to tubes.

The same goes for steam engines. We treat them like our mothers.

“They say steam gets into your spine, the same way Blackpool goes through rock”.
https://en.wikipedia.org/wiki/Rock_(confectionery)#LetteringThe same is probably true of VTs.

 

[dlgoff]

“They say steam gets into your spine, the same way Blackpool goes through rock”.
https://en.wikipedia.org/wiki/Rock_(confectionery)#Lettering

Yummy! Sugar!

 

[dlgoff]

The same goes for steam engines.

Seriously. That's why my rule at the antique mall is: "If it doesn't have wires, pass it by."

 

[anorlunda]

sexy, elusive and magical element of all of high end audio

Audiophiles appear to be particularly prone to metaphysical qualities of sound. That makes them prime targets for people who want to make money off of them.

I would compare it with the quality of human beauty. Selling beauty is also a huge industry.

 

[Rive]

Selling beauty is also a huge industry.

I don't know if this qualifies for this part (while fits the part about audiophiles) but some companies already started to produce fake vacuum tubes (with LED lights inside: optionally with different colors).

I does not dare to link any in this topic

 

[dlgoff]

This Edwards High Vacuum foreline trap doesn't measure nor is it electrical but does look beautiful servicing two Edwards 8 two stage rotary pumps.

 

[geoelectronics]

So it wasn't a Beckman Instruments Helipot? Interesting.
[/PLAIN]
http://vimeo.com/97150132']http://vimeo.com/97150132']Helipot history.

Electro Scientific Industries, ESI- DekaStat, DekaPot, DekaVider series. Most are Kelvin-Varley resistive dividers. This one pictured is a simple adjustable resistor I just finished restoring this year.Beautiful.inside and out, all wire wound resistors using non inductive Ayrton-Perry wiring.
Geo>K0FF

 

[dlgoff]

Electro Scientific Industries, ESI- DekaStat, DekaPot, DekaVider series. Most are Kelvin-Varley resistive dividers. This one pictured is a simple adjustable resistor I just finished restoring this year.Beautiful.inside and out, all wire wound resistors using non inductive Ayrton-Perry wiring.
Geo>K0FF

Very nice work @geoelectronics. I bet that was a tedious job. Curious; what tolerances were the resistors? Thanks for sharing.

 

[berkeman]

This one pictured is a simple adjustable resistor I just finished restoring this year

Very cool. What does "X" mean on the selectors?

 

[Klystron]

Funny how we associate good electronics with certain brand names, apropos Beckman Instruments.

Notice a vintage O-scope; think Tektronix though HP likely made as many instruments. Many people referred to home refrigerators as "Frigidaires" when I was a child, regardless of the actual brand name. Perhaps the most egregious example would be IBM popularizing the acronym PC for any personal computer.

 

[dlgoff]

What does "X" mean on the selectors?

I just downloaded the the Instruction Manual DB877_im.pdf (attached)

All decade dials can be turned 360°, which allows settings to be changed rapidly and directly from X to 0. Seven of the decade dials (0.1 ohm – 100 kilohms) have an X position that corresponds to ten steps on the dial or one step of the next higher decade dial.

 

[geoelectronics]

Very nice work @geoelectronics. I bet that was a tedious job. Curious; what tolerances were the resistors? Thanks for sharing.

I just downloaded the the Instruction Manual DB877_im.pdf

Correct, X=10

ESI was merged several times, the main survivor today of the corporate takeovers is IET Labs.

Accuracy when Tegam made them =

Specifications
CHARACTERISTIC SPECIFICATION
Accuracy
Resistance Increments See Table 1
Initial (0.01% + 7 milliohms)
Long-term (0.02% + 10 milliohms)
Short-term Switching Repeatability 1 milliohm (typical)
Number of Decades Eight
Total Resistance 12.111111 megohms

The switches are ceramic form, solid silver in most and each contact uses the upper and lower segments in parallel.

I've written about some others like Leeds & Northrup on eHam. (if not allowed on PF just tell me for deletion, no problem)

Geo>K0FF

 

[dlgoff]

Thanks for sharing some history; ESI's merges.

Accuracy ... Initial (0.01% + 7 milliohms)

Milliohms? Do you have a way of testing these resistors? I'm guessing a wheatstone bridge?

The switches are ceramic form, solid silver in most and each contact uses the upper and lower segments in parallel

That must have been an expensive piece of test equipment in it's day.

I've written about some others like Leeds & Northrup on eHam.

PM me a link if you don't mind. I'd like to see more of your handy work. :)

 

[geoelectronics]

You asked: "Milliohms? Do you have a way of testing these resistors? I'm guessing a wheatstone bridge?"

Yes right on. a guarded Wheastone bridge bu ESI for high resistances up to 12,000 MegOhms, and an ESI Kelvin Bridge for the very low stuff (old tech but accurate), also a pair of HP-Yokogawa meters, one for milliOhms, the other goes up to tera ohms Modern tech but like 1980's? PS the much older bridges give more digits in the reading).
Guarded simply means the actual bridge is in a box and float above ground, leaving the two leads free of ground reference (unless you force them), and the case and rack are grounded. This gives 3 leads to the device being tested, one being grounded, for interference relief. That's why all the lab grade resistors and capacitors have 2 leads plus ground."That must have been an expensive piece of test equipment in it's day."

Stuff like that wasn't even in the catalogs I used back then...Geo

PM me a link if you don't mind. I'd like to see more of your handy work. :)
(done)

Geo

 

[dlgoff]

Back in the 1960s there was an article in the Scientific American magazine, https://www.jstor.org/stable/24931636?seq=1#page_scan_tab_contents. And being a kid then I wanted to give it a try. The only thing I managed to do was finding a 9,000 volt neon sign transformer used for the power supply. The project was too much for this 14 year old at the time but the desire to make a HeNe gas laser never left. So when I came across this lasing tube on eBay, I couldn't resist. It's truly a beauty.

 

[jedishrfu]

Does it still work?

 

[Bystander]

You think he won't try it? How much?

 

[dlgoff]

Does it still work?

No. Not enough He.

edit: However, the same tube type in this laser does work.

 

[Bystander]

How old? The He diffuses through the glass that quickly that He-Ne's have to be "stale-dated?" Was aware of the "problem," but not that it was that significant.

 

[dlgoff]

How old? The He diffuses through the glass that quickly that He-Ne's have to be "stale-dated?" Was aware of the "problem," but not that it was that significant.

The number/code engraved into the cathode is 534-84. So I'm assuming the tube was made in 1984.