Importance of vacuum/pressure testing

[PapaWhitebeard]

How did we go from vacuum testing to vacuum tubes... I'd post a pic of my vacuum tube tester to try steer things back on to testing... but that would be flawed logic, & this is far nicer to look at...
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Bhwahahahaha is that yours? I LOVE it! I see a bunch of 12AX7/AU7 type preamp tubes. Is that power tube an EL34 or a big 6L6? It’s gorgeous.

Nice blackplate halos on those 12AX7’s of AT7’s or whatever they are. I used to be able to ID most of that stuff on sight but it’s been a LONG time since I had loads and loads of tubes… (although I still gots some for sure )

 

[J D]

It's my dads, along with a multitude of other valve based components & half dozen valve amps, driving a bunch of electrostatic speakers - I'm just the muggins that has to keep it all working.
I'd post more pic's but (aside from steering us further off topic) most of it is shamefully dusty

 

[ZeroJunk]

I put a new socket in a friends TL-922 amplifier yesterday. Once the pins start dripping solder really might as well replace the socket. Filaments 5 volts at 15 amps. Lot of current. 3-500Z tube. Not audio obviously.

 

[PapaWhitebeard]

I put a new socket in a friends TL-922 amplifier yesterday. Once the pins start dripping solder really might as well replace the socket. Filaments 5 volts at 15 amps. Lot of current. 3-500Z tube. Not audio obviously.

15 amps!!! Be careful, fella

 

[ZeroJunk]

15 amps!!! Be careful, fella

Just five volts. Probably wouldn't even feel it. Flip the amp over and there is about 2500 volts on the anode.
It will kill you.

 

[PapaWhitebeard]

Just five volts. Probably wouldn't even feel it. Flip the amp over and there is about 2500 volts on the anode.
It will kill you.

Yep… that big heavy metal inside those… some of those capacitors can kill you even if the amp is unplugged… I remember what I was taught “be the one handed electrician” (right so it doesn’t send current straight through your heart)

 

[Chevboy0167]

The song of my people..... except it's the 40,000 bigger brother!

The toilets I could flush down the block on key up would tickle me pink.

 

[ZeroJunk]

The song of my people..... except it's the 40,000 bigger brother!

The toilets I could flush down the block on key up would tickle me pink.

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BBI is building one for somebody now that is supposed to do like 170,000 watts.
Of course, you would have to pay the power company to bring you in an 800 amp service.

Those super bowl guys are serious.

 

[Chevboy0167]

Welp... I better step my game up then yeah?

 

[Chevboy0167]

In all fairness, Klystron tubes probably not the best choice.

But the wattage would come in handy.... if I could aim it dead center at the receiving antenna!

 

[PapaWhitebeard]

In all fairness, Klystron tubes probably not the best choice.

But the wattage would come in handy.... if I could aim it dead center at the receiving antenna!

Or… like… blow up the Death Star

 

[Chevboy0167]

Back on topic.... I used these silicone plugs to test a Husqy 460 last yr. Gotta get creative with what ya got unless you doing this every day.

Strato sucks!

 

[Bob Hedgecutter]

Back on topic.... I used these silicone plugs to test a Husqy 460 last yr. Gotta get creative with what ya got unless you doing this every day.

Strato sucks!

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And see, no specialised metal plate, no Stihl or Mightyvac pump needed- yet you still got the job done- and most probably without distorting the manifold.

 

[TheTone]

Remember the tube testers in drug stores ?

Yes! Drug stores had them in the days when you could get a milkshake at the soda fountain. They were almost the size of refrigerators, or so it seemed to a small boy. I was probably 6 or 8 years old and would go with my dad when he would bring a bag of tubes from a non-functioning TV or radio for testing. First you would look up the tube number, and the book would tell you the right socket to put it in and the various dial settings. It would then tell you if the tube was shorted, good, or weak. It was free and completely do it yourself. I don't remember if the drug stores sold tubes or just used the testers to bring people into the store. Those trips were one of the fun memories of being a 50's kid.

 

[Chevboy0167]

I was gifted an old suitcase style tube tester. Can not remember the brand at the moment.... hmmm.... Or if it even still works!

 

[StihlsawuserMS361]

I remember those testers also. My Dad bought a replacement tube, and for whatever reason, I tested the "new" tube, and it failed. Saved us a second trip.
Back in the days when we fixed things rather than tossing them away

 

[J D]

I was gifted an old suitcase style tube tester. Can not remember the brand at the moment.... hmmm.... Or if it even still works!

Might be worth digging it out & seeing... they can be surprisingly valuable