Beauty of old electrical and measuring things, etc.

[dlgoff]

I can't wait to fire up this beauty. Don't worry; safety first.

I made a 25 kV power source from an old color TV to supply the old X-ray tube. But even though the radiation from it is considered low LET (linear energy transfer), there is still danger from absorbed doses. My survey meter measures absorbed dose in mrads/hr. The biological risk from radiation exposure (or equivalent dose), measured in rems, is determined by LET giving a radiation weighing factor; in this case the factor is equal to one. Note that 100 rem would make you sick.

I measured 1 mrad/hr at ~10 feet from the front of the display (or 1 rem/hr) and 150 mrad/hr at the center of the tube’s output (or 150 rem/hr). So don’t try this at home kids.

For safety reasons, I incorporated a key locking power switch (with a big red indicator) and a 25 kV on/off push-button switch at the end of a long cable to get some distance from the tube when in operation. I also made sure there was a Danger and a Warning sign visible.

Here are two photos; one up close un-energized and one at a distance energized.

 

[berkeman]

Pretty amazing work, Don. I'm glad you took safety aspects into consideration.

 

[dlgoff]

I'm glad you took safety aspects into consideration.

Safety should always enter the equation. Knowing that you feel the same, maybe a sticky for dangers and safety in engineering would be appropriate. We haven't lived this long for not respecting electricity. I'm sure others would have great advice.

 

[berkeman]

Safety should always enter the equation. Knowing that you feel the same, maybe a sticky for dangers and safety in engineering would be appropriate. We haven't lived this long for not respecting electricity. I'm sure others would have great advice.

Interesting idea. That might make a good EE forum stickie thread. Let me think on it a bit...

 

[Planobilly]

"Don't kill yourself having fun"

I try my best to remember that, on the ocean, in the air, and pokin round in the high voltage!

Cheers,

Billy

 

[DrClaude]

Here are two photos; one up close un-energized and one at a distance energized.

https://www.physicsforums.com/attachments/x-ray_off-jpg.96459/

[PLAIN]https://www.physicsforums.com/attachments/x-ray_on-jpg.96460/[/QUOTE]
The images are broken.

 

[berkeman]

Images seem fine to me. Are you not seeing anything?

 

[Borg]

Images seem fine to me. Are you not seeing anything?

I am also unable to see the pictures. And, when I click on them to "view image", I get a PF permission error.

 

[dlgoff]

The images are broken.

I re-uploaded the images. Can you see them now?

 

[jim hardy]

images in 121 don't show for me - firefox...

Click "View Image " yields

 

[Borg]

Click "View Image " yields

That's exactly what I'm getting also. It seems that PF is blocking access to some of us.

 

[dlgoff]

How about now Jim?

 

[Borg]

How about now Jim?

Working for me now.

 

[jim hardy]

Whatever somebody did - i see two fine images now !

 

[berkeman]

How about now Jim?

How'd you fix it for them?

 

[dlgoff]

How'd you fix it for them?

I re-uploaded the two pics. Initially, I used the ones from the Conversation we had, hoping to save a little server space.

 

[berkeman]

Ah, and that's why I could see them -- they were likely still in my cache.

 

[dlgoff]

Here are a couple oldies:

In rough condition but repaired and working (w/ a old carbon filament bulb); from the Swivelier Company, Inc.

Cute little clip-on 75W 125V (with bulb); from the Leviton Manufacturing Company, Inc.

 

[dlgoff]

My girlfriend knows what makes me happy. A couple months ago she picked up this old Western Union Telegraph Company telegraph relay. Even though it's missing the metal tag, I'm fairly sure it's the 4D, 100 ohm model. It took a lot of Q-tips to clean it up to find, MFG BY HARDWICK FIELD & LEED...

The only other thing I did was to repair the broken coil lead-in wires so that it would function. Then I figured I should try to find a key (bug) so I could demonstrate it. While looking around on ebay.com, I came across a fairly old practice key that someone had tried modifying way back when; missing the buzzer and added audio transformer, vacuum tube rectifier tube, and socket. Not sure what they were trying to do. Anyway my attention shifted away from the key.

Here's the Freed-Eismann audio transformer (though about sending it to @Phanobilly for the vacuum tube amp he's building )

But this old Raytheon BH Vacuum Tube and Benjamin shock-absorbing socket makes me even happier .

It's around 90 years old and it still works. Here's an image from a .pdf, compliments of www.clarisonus.com, introducing the tube in the October, 1926 edition of Radio News.

 

[davenn]

love the new additions to your collection, Don

 

[berkeman]

this old Western Union Telegraph Company telegraph relay

I recently learned why the "relay" part of ARRL was important. Anybody else know? What a fundamental and important part of history...

 

[dlgoff]

I recently learned why the "relay" part of ARRL was important. Anybody else know? What a fundamental and important part of history...

Not sure; radio relay? As in hopping messages across the country?

 

[dlgoff]

love the new additions to your collection, Don

Thanks. I was lucky to get them.

 

[berkeman]

Not sure; radio relay? As in hopping messages across the country?

Yeah, exactly. Such a primitive technology with spark coils, but with long enough Rx antennas and enough people listening, you could relay Morse code messages across the country.

 

[lastfsdfsd23]

wow ! this equipment is so beautiful. i just wondered
to seen it. just awesome.

 

[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. Here's a outside and inside (powered & set to 140 volts) view of this 30 amp beauty. :)

 

[dlgoff]

My beautiful coffee table.

 

[DrClaude]

My beautiful coffee table.

That brings back memories. My father was an electrician and, when I was young, we used to use ceramic insulators (like the left-most red one in your picture, but blue) as door stops.

 

[dlgoff]

... we used to use ceramic insulators (like the left-most red one in your picture, but blue) as door stops.

I can see using them like that. A blue one would be a nice addition. I've got boxes of insulators and for the most part only duplicated a few types. However different colors counted as not being duplicated. Memories is what this thread is all about.

 

[DrClaude]

I can see using them like that. A blue one would be a nice addition. I've got boxes of insulators and for the most part only duplicated a few types. However different colors counted as not being duplicated. Memories is what this thread is all about.

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...)