Beauty of old electrical and measuring things, etc.

[dlgoff]

I don't think my father kept them. Otherwise, I would gladly send you one. (Not sure how much it would cost to mail such a beast...)

Oh. That's okay, but thanks for offering. Actually I should be thinking about downsizing.

I told daughter that when I'm dead and gone, don't sell the beauties, just give them away.

 

[ernic]

Nice work

 

[dlgoff]

Nice work

Thank you.

 

[dlgoff]

I've been trying to get a metal deposition system put together but had to do a little beautification on this old General Radio Co. W30M Variac that I'm incorporating.

To get the current to heat the Tungsten evaporation element, like this circuit in the old Variac's manual,

I picked up this (after two days of cleaning) beauty, "supplementary transformer" (actually 0 to 5 vac power supply).

Check out the Simpson current transformer and ac amp meter.
Here's a couple of pics of what I have so far for the deposition system that I just pumped down and tested at ~100 amp.

 

[jim hardy]

wow ! just Wow !

 

[dlgoff]

I've been trying to get a metal deposition system put together ...

Since I mentioned this here in my beauty thread, I thought I might as well show a pic of my first thin film Copper deposition.

 

[jim hardy]

Is that a copper mirror reflecting Physics forums homepage from screen?

Impressive !

Would it deposit copper coating on a metal part ?

 

[dlgoff]

Would it deposit copper coating on a metal part ?

I believe so. I have to clean all the metal components in the bell jar after every run. I don't think that the film would be very strongly attached as it would be from sputtering.

BTW yes. that's the copper on glass slide reflecting the PF home page.

 

[DrClaude]

Since I mentioned this here in my beauty thread, I thought I might as well show a pic of my first thin film Copper deposition.

View attachment 108747

Beautiful! But be careful not to go Anthony Weiner on us

 

[dlgoff]

Beautiful! But be careful not to go Anthony Weiner on us

Got it! Hoping you don't go Andrew Breitbart on me.

 

[dlgoff]

I’ve had this vintage, 1950’s, blue Kenmore sun lamp for a while but didn’t know how to display it until now. It’s coming in handy to work on my vacuum system I’m putting together.

 

[dlgoff]

...work on my vacuum system...

I thought I'd share a couple pics of the vacuum deposition (now sputter) system I've put together with mostly old "Beauty" components. I am just about ready to give it a try to see if it'll sputter copper onto glass. I've added a little heat exchanger to bring the temperature down on the electrode cooling air and made a HV tube power supply for the sputter potential (adjustable up to ~2kV). Also have Argon that I'll introduce after a good pump-down to help get a copper plasma.

 

[Averagesupernova]

I have had this little detector for quite a few years now. I don't recall what I paid for it but a HAM that I used to work with sold it to me for what I recall being quite reasonable. He is deceased now so it means a bit more to me. Thought I would make it my avatar but it also fits in this thread just fine.

 

[dlgoff]

I have had this little detector for quite a few years now. I don't recall what I paid for it but a HAM that I used to work with sold it to me for what I recall being quite reasonable. He is deceased now so it means a bit more to me. Thought I would make it my avatar but it also fits in this thread just fine.

View attachment 131256

Thanks for sharing this beauty. Can you explain a little how it works?

I understand how it can give meaning to you. My HAM mentor (W0AFQ) would be in his 90s now and I'd love to let him know that his mentoring made a huge impact in my life.

 

[Averagesupernova]

Such variability, bordering on what seemed the mystical, plagued the early history of crystal detectors and caused many of the vacuum tube experts of a later generation to regard the art of crystal rectification as being close to disreputable.

The above is taken from a wiki article: https://en.wikipedia.org/wiki/Cat's-whisker_detector
-
Early semiconductors were not taken at all seriously since there was an association with the instability of the cat's whisker detector. I have never tried using one but as a kid I had a lot of fun tinkering with 'crystal' radio using a germanium diode. After a while I learned to plug the output of my crystal set into the mic input on a tape recorder and listen through the external speaker jack. My first experience with understanding amplification.
-
With cat's whisker detectors as I understand you would poke around with the thing until you got acceptable reception. Of course I can imagine trying a new stab at it because it was a shot in the dark and I would get greedy thinking there was a better spot on the crystal. I would assume moving the detector would also detune what it was hooked to. So if the detector gets bumped it probably also means a retune. Todays cell phone equipped kids have no idea what it took to get here. And for that matter I probably underestimate it plenty too.

 

[anorlunda]

After a while I learned to plug the output of my crystal set into the mic input on a tape recorder and listen through the external speaker jack. My first experience with understanding amplification.

Wow, I can relate to that. I had a very similar experience in my youth that greatly influenced my career. But my experience was playing with a TR-10 analog computer. It gave me an intuitive feel for transient dynamics, and the relationship to DIFF-EQ, and an appreciation for energy (the charge on those capacitors in the TR-10, no capacitors no dynamics). That started me down an analytical path much different than the hands-on path of you, @berkeman, @jim hardy and others here on PF. But in terms of a early life experience that influenced a young mind, it was very much the same.

 

[jim hardy]

It gave me an intuitive feel for transient dynamics, and the relationship to DIFF-EQ, and an appreciation for energy (the charge on those capacitors in the TR-10, no capacitors no dynamics). That started me down an analytical path much different than the hands-on path of you, @berkeman, @jim hardy and others here on PF. But in terms of a early life experience that influenced a young mind, it was very much the same.

Wow i remember a lab course we took called "analog computing" . I don't remember whether it was a "Pace" we had in the lab or something similar... but i knew i should be able to relate to the hardware. As with most things academic i struggled with the equations, was in danger of failing.

One Friday evening something clicked - it dawned on me all you had to do was arrange the differential terms in order and wire up the integrators same way, set the gain & time constant resistors and run it. So i did all our semester's labs over that weekend, wrote them up with great enthusiasm and got "A" . Still one of my favorite memories.
That 'feel' you mention was for me integral-differential relations. I could relate them to capacitance.
Some years later i encountered and understood Ray Nath's analog computer that solves the six group delayed neutron equation for startup testing of reactors. EAI built it, too.

I guess that's why i am drawn to analog electronics, it's a familiar language.

Life's little coincidences , eh ? They shape us.
Buy your grandkids some small hand tools and a junk VCR to take apart. Have them put the little screws in a bottle for fixing things later.
Kids love it, it teaches them finger dexterity and curiosity that pay off in later life. My daughter fixes everything from icemakers to car windows and is teaching her kids to do the same. .

old jim

 

[TurtleMeister]

The above is taken from a wiki article: https://en.wikipedia.org/wiki/Cat's-whisker_detector
-
Early semiconductors were not taken at all seriously since there was an association with the instability of the cat's whisker detector. I have never tried using one but as a kid I had a lot of fun tinkering with 'crystal' radio using a germanium diode. After a while I learned to plug the output of my crystal set into the mic input on a tape recorder and listen through the external speaker jack. My first experience with understanding amplification.
-
With cat's whisker detectors as I understand you would poke around with the thing until you got acceptable reception. Of course I can imagine trying a new stab at it because it was a shot in the dark and I would get greedy thinking there was a better spot on the crystal. I would assume moving the detector would also detune what it was hooked to. So if the detector gets bumped it probably also means a retune. Todays cell phone equipped kids have no idea what it took to get here. And for that matter I probably underestimate it plenty too.

Brings back memories. I did the exact same thing.

 

[TurtleMeister]

I've been trying to get a metal deposition system put together but had to do a little beautification on this old General Radio Co. W30M Variac that I'm incorporating. Here's a outside and inside (powered & set to 140 volts) view of this 30 amp beauty. :)

View attachment 105393
View attachment 105392

One of the first companies I worked for used a lot of these 30 amp variacs. Except I think ours where manufactured by Superior Electric. When the company shut down I was able to get a few of them along with some power analyzers.

I love your sputter machine. Very nice job with all of these restorations.

 

[dlgoff]

I can imagine trying a new stab at it because it was a shot in the dark and I would get greedy thinking there was a better spot on the crystal.

Reminds me when my old Ham mentor showed me how to modify a crystal's frequency with a lead pencil.

Thanks for sharing and explaining.

 

[davenn]

Reminds me when my old Ham mentor showed me how to modify a crystal's frequency with a lead pencil.

ahhhh yes ... another old trick :)

 

[dlgoff]

Kids love it, it teaches them finger dexterity and curiosity that pay off in later life.

With a little help, like I got from my old Ham mentor, techniques for making things comes also.

 

[dlgoff]

I love your sputter machine. Very nice job with all of these restorations.

I've made lots of tests leading to modifications on the thing. Not all that easy to get good results... Well not yet, but I just received some new caps in the mail for the HV supply from old jim. Thanks a bunch @jim hardy

 

[Averagesupernova]

Reminds me when my old Ham mentor showed me how to modify a crystal's frequency with a lead pencil.

Thanks for sharing and explaining.

I have heard of that but never been in a position to try it.

 

[Baluncore]

I have done it and it works well with the old WW2 crystal holders where the crystals were clamped between metal plates. These days the hermetically sealed crystals makes it difficult. http://www.af4k.com/crystal_holders.htm

If the crystal frequency was too low you polished the plate to reduce the mass and so raise the frequency. If you went too far, you use the pencil on the entire surface, that increased the mass of the crystal and so took the frequency back to where you should have stopped polishing earlier.

It was common to find an initial letter or a digit written on the crystal in pencil, left half a century ago by the previous crystal polisher. I always wonder who that was and what became of them. On average, I think it was a young woman, who later married a returned soldier to generate the baby boomers.

 

[dlgoff]

If the crystal frequency was too low you polished the plate to reduce the mass and so raise the frequency. If you went too far, you use the pencil on the entire surface, that increased the mass of the crystal and so took the frequency back to where you should have stopped polishing earlier.

Oh yea. I remember now about polishing. I think my mentor used the pencil eraser for that.

 

[dlgoff]

Vacuum leaks are a pain in the butt. So I picked up a couple vacuum gauge beauties that helped me find those leaks. With a good vacuum now, I just tried evaporated Aluminum on a glass slide. Here are the gauges and some Aluminum reflections.

 

[jim hardy]

Beautiful work, dlgoff !

 

[berkeman]

How big is that sheet in the bottom pic? It looks giant!

 

[dlgoff]

How big is that sheet in the bottom pic? It looks giant!

It's a 1" x 3" glass slide.

 

[dlgoff]

Beautiful work, dlgoff !

Thanks Jim.

 

[berkeman]

It's a 1" x 3" glass slide.

Oh, you're holding it up well above the grass. I thought it was laying on the grass. Big difference...

 

[dlgoff]

Oh, you're holding it up well above the grass. I thought it was laying on the grass. Big difference...

Yea. I'm holding the slide. Here's a couple more shots.

 

[dlgoff]

I've done a little updating of my vacuum deposition system. I needed a better vacuum in order to get cleaner depositions, so I added a rotary vacuum pump. I was also having a gauge tube problem because of a ground loop, so I earthed the piping and gauge controllers to a outside Earth grounding rod. Now I'm getting really low and stable pressure readings. Here are pictures of the system showing the new pump, ground wiring, and vacuum gauge readings.

I use the mechanical gauge (0 to 30 in Hg) as a reference for when to power up the foreline gauge (20 to 0 mm Hg) which serves as a reference for when to power up the vacuum chamber gauge (100 to 0 mTorr). Now I'm getting really nice Aluminum on glass slide depositions.

 

[dlgoff]

Here's a beauty you don't see every day. This rectangular loop antenna came out of a old tube type table top radio. It measures 14" X 10 1/2". I was a youngster when I took this out of a non repairable radio. I can't remember who made it.

The loops have spacers that lock into place with little wooden dowels. Three of these dowels were missing and I replaced with heat-shrink covered paper Q-tip shafts.

Here's a spacer with dowel.

Here how it was terminated with the lead-in wires.
edit: corrected typo

Any old times here ever seen one of these in a radio?

 

[jim hardy]

Any old times here ever seen one of these in a radio?

Not one nearly so robustly built.

Of what material are those slotted brackets made ?

 

[dlgoff]

Of what material are those slotted brackets made ?

I'm glad you asked that. I never looked into what the metal parts were made of. I had always thought the loops were made of a hard copper alloy. I just now used a magnet on the brackets. They're nonmagnetic and appear to be brass but on closer examination and testing with an ohm meter, they have infinite resistance and turn out to be made of "pressed paper" (and looks like the same find of paper used for the tubes you would find old radio coils wrapped on). Whereas the loops are really magnetic, so more than likely they're copper plated steel. The resistance of loops from end to end (measured on lead-ins) is 0.1 ohm. I searched the internet and only found one antenna that was similar. It was an http://www.ebay.com/itm/RADIO-LOOP-ANTENNA-Vintage-/112511382955?hash=item1a323375ab:gIUAAOSwIaFZKcHu and one can Buy it Now for US $99.00. Here's the picture of it.

 

[jim hardy]

Whereas the loops are really magnetic, so more than likely they're copper plated steel.

I wondered. The brackets do look like steel but that would short the turns ?
I guess the loops needn't be solid copper just a thick plating - at RF skin effect keeps current on the surface ?

 

[dlgoff]

... but that would short the turns ?

... making it more like a single loop antenna.

... just a thick plating - at RF skin effect keeps current on the surface ?

... thick enough depending a little on the RF's frequency.
from https://en.wikipedia.org/wiki/Skin_effect

 

[Joseph M. Zias]

How about Sensitive Research. They made some absolutely beautiful instruments in wood cases. I remember some of their true rms meters.
Ever hear of a "ballistic galvanometer". It was used to measure charge. Then there were those "leeds and Northrup" potentiometers to measure
temperatures with a thermocouple.

Oh, so many. Well, you have got me to thinking, now if you could just convince my wife that we should have a museum.

 

[dlgoff]

How about Sensitive Research. They made some absolutely beautiful instruments in wood cases. I remember some of their true rms meters.

Nice stuff indeed. Radiomuseum.org tell about some items made by the Sensitive Research Instrument Co. Here's are some images from their site.

Ever hear of a "ballistic galvanometer". It was used to measure charge.

Oh yea. They weren't made by Sensitive Research Instrument Co., but I used them in my University's physics labs. Very accurate way to measure charge.

...you have got me to thinking, now if you could just convince my wife that we should have a museum.

Yes you should have a museum. Show your wife this thread and tell her it's for the good of people's education and you want to be a part of that. It's been a learning experience for me and maybe for the both of you too.

BTW: Welcome to Physics Forums. Hope you'll stay here and post some good stuff.

 

[dlgoff]

Back on post #94 I showed an antenna that I built for the Narco Superhomer Nav receiver that's shown working in post # 98. Well now, I've found the actual Narco antenna for this radio. It's condition is a little rough but it should clean up okay. I'll post a couple pictures of it now and later some restored pictures. Then I'll replace the one I built with it and do some testing.

 

[dlgoff]

I have a lot of electron vacuum tubes in several cardboard boxes that I've been wanting to organize. So I bought some generic sleeved tube boxes and this old tube caddy. Part of one side is a little faded. It looks like part of the caddy had been exposed to light for a long time while the the other part was shaded.

 

[jim hardy]

Is there a similar thread in Mechanical Engineering for old machinery enthusiasts ?

 

[berkeman]

Zowie!

 

[OmCheeto]

I have a lot of electron vacuum tubes...]

Speaking of tubes, have you watched Star Trek's "The City on the Edge of Forever" recently?
I watched it last night, for the first time in many years.

Tubes galore!

Of course, I immediately thought of you, as the year was 1930, and I was curious if they had such tubes back then.
And Spock and Kirk were working for 15¢/hour for 10 hours/day, and rent was $2/week, which netted them $19/week.
I suppose I could just google what prices for tubes were back then, but I figure you might have the prices and dates stamped on some of your boxes.

 

[Averagesupernova]

I wonder what those tubes are filament wise. I would bet 12 volts. Notice there are 10 of them. Anyone see where I am going with this?
-
I guess they wouldn't need to be powered but for some reason I seem to recall thinking that they were in fact 'lit up'.

 

[jim hardy]

I wonder what those tubes are filament wise.

1930's? Indeed they resemble the #30 triodes in my antique radio from that era.
https://www.tubedepot.com/products/30-triode-st-shape

Before rural electrification when so many radios were battery powered lots of tubes had 1 to 2 volt filaments .

Junkshop nearby has a bushel basket of such tubes, I've resisted the temptation so far... but i probably ought to get all his 30's for my radio.

 

[Averagesupernova]

I have a 6 volt radio with 6 one volt filament tubes. I believe it is an Admiral. It needs an output transformer. I walk by it every day many times as it is in my hallway but it never occurred to me to post it in this thread. I'll have to get a pic.

 

[jim hardy]

It needs an output transformer.

Hammond still makes vintage audio transformers.

Do you know what impedance you need? I'll keep an eye peeled in local junkshop . vintage parts emporium .