tube-a-lou
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It's Here!
Hickok 600A
- Thread starter tube-a-lou
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toxcrusadr
Omelette au Fromage
What is that smell anyway? If you could bottle that, you could probably sell it to tube audio geeks. Better yet, Glade Plugin "Vintage Tube Scent". Your other half has Glad Plugins all over the house including your shop? Boy do we have the solution for you! Comes in Antique for the 4-5 Pin Tester crowd or Mid-Century for the 7 and 9-pin Miniature crowd.
Quite the opposite.
Modern CFL's have vanishingly small mercury content. Under 5 mg for the small bulbs. The long tubes have anywhere from about 5 mg to 40 mg, which is considerable, depending upon type and construction. These now generally have about 5 mg. The big issue is the vapor form, of course.
An 83 tube, to contrast, has about 0.5 to 1 mg. (It would have to be this way, of course, because the more there is the poorer the vacuum and the worse the tube functions.) Hence my comment about worrying more about the CFL than about the remote possibility of a broken mercury-vapor rectifier tube.
In general, I worry far more about bicyclists on the sidewalk, taxi drivers who run lights, and crazy people on the subway than I do about mercury from tubes. Although I do limit my consumption of large ocean fish, as these are now riddled with mercury from coal-fired power plants.
Mid-century comes with a hint of teak or walnut, while the 4-5 pin scent comes with delightful overtones of mildewed basements and barn rot, with a subtle undertone of burning bakelite.
tube-a-lou
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toxcrusadr
Omelette au Fromage
I am surprised to hear the mercury in an 83 is such a tiny amount. Given its density, 1 mg wouldn't even be visible unless you were looking right at it.
I only thought there was a lot more because I have Hickoks and the 83's I looked at always look like they have stuff inside the glass. A flake here, a fragment there. Maybe it's just gettering or mica bits. I thought there was the equivalent of several drops in there. RCA's datasheet doesn't say, so how do we know? Not that I don't trust your info, just curious.
I only thought there was a lot more because I have Hickoks and the 83's I looked at always look like they have stuff inside the glass. A flake here, a fragment there. Maybe it's just gettering or mica bits. I thought there was the equivalent of several drops in there. RCA's datasheet doesn't say, so how do we know? Not that I don't trust your info, just curious.
tube-a-lou
Addicted Member
toxcrusadr
Omelette au Fromage
Those wafer switches are phenolic plastic and will absorb the small amount of oil in DeOxit which can cause electrical conductivity and leakage. Best not to spray them. I use a piece of cardstock (the kind that fall out of magazines), dampen it with DeOxit and slide it back and forth between the contacts. Move the switch to a new contact and go again. You can also use a Qtip on a bunch of them at once if it's not drippy so you don't get too much on the plastic wafer. Let the whole thing dry really well before firing it up.
Pots, it depends on what they are, but generally I hose them out with regular DeOxit or some cheaper tuner cleaner I have, using the tiny straw to get it inside. Pack a rag around/under to catch it and work the pot while it's saturated. Once clean give a quick final shot of Deoxit Faderlube. Read the sticky in DIY about deoxit for more info.
As for the cord, with a wood case you hardly need grounding but there is a metal plate there so you could use a 3-prong and connect the ground wire to the panel. If the cord is OK I'd leave it as is, myself.
What's wrong with the roll mechanism?
Pots, it depends on what they are, but generally I hose them out with regular DeOxit or some cheaper tuner cleaner I have, using the tiny straw to get it inside. Pack a rag around/under to catch it and work the pot while it's saturated. Once clean give a quick final shot of Deoxit Faderlube. Read the sticky in DIY about deoxit for more info.
As for the cord, with a wood case you hardly need grounding but there is a metal plate there so you could use a 3-prong and connect the ground wire to the panel. If the cord is OK I'd leave it as is, myself.
What's wrong with the roll mechanism?
tube-a-lou
Addicted Member
It get's stuck at times. I had to repair the bias pot the stopper at the beginning
of the pot by 0 got damaged so I had to remove the screws of the pot and reset
the brass tab at the end to be flat and slightly turn the other contact so the control
knob will turn from 0 to 100.
of the pot by 0 got damaged so I had to remove the screws of the pot and reset
the brass tab at the end to be flat and slightly turn the other contact so the control
knob will turn from 0 to 100.
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Exactly what I was thinking. Used a 605A for years and didn't worry about about the 83 ever. Now if you test an 83 tube and you get to see the mercury vaporize that will get your attention. One of those WTF momments.
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Was at the ARCI radio fest back in the day when 45 tubes brought good money. Pulled one out of the pocket of my coat slipped out of my hand and after batting it 3 times it finally made it's way to the asphalt.
tube-a-lou
Addicted Member
Ouch! that must of hurt!
tube-a-lou
Addicted Member
Here's more photo's of the underside, I redid the bias pot, when I first look at it the swiper
went under the brass end tab in which when you would set the bias, the numbers on the dial
was off. It seems to line up better now from "0" to "100". I also replaced the 50uf cap with
a new one and the .1uf as well, didn't see any more caps, I did test a few resistors and the
one's I could test they were close within 2% to 5%. the other ones I will have to leave till I get
spares I don't want to start digging into them and if they break I'll be stuck till I order new ones.
went under the brass end tab in which when you would set the bias, the numbers on the dial
was off. It seems to line up better now from "0" to "100". I also replaced the 50uf cap with
a new one and the .1uf as well, didn't see any more caps, I did test a few resistors and the
one's I could test they were close within 2% to 5%. the other ones I will have to leave till I get
spares I don't want to start digging into them and if they break I'll be stuck till I order new ones.
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arts
Addicted Member
There's something I've never noticed before,the switch on the lower right corner beside the wheel for the roll chart. Mine doesn't have this,and when I google image'd the 600A,it seems that some have it,others don't. They all look like an afterthought because of the separate label plate. I wonder if it's factory or was sold as an upgrade/option?
I don't know if you've seen this document by Daniel Schoo regarding the calibration of the Hickok 539C.
http://www.desmith.net/NMdS/Electronics/Hickok/Hickok 539C Calibration V4.1.pdf
I think there are enough similarities to your unit to be helpful. I used an Oscilloscope to balance the rectifier output pulses on my Western Electric KS-15750-L1 tube tester made by HICKOK which is based on the 539 models.
Balance Pot:
In addition to the usual stuff, my unit allows me to measure plate, cathode and screen grid currents.
If you really want to learn how a tube works, fix a tube tester. It took a while to figure it out and calibrate it properly but it's a useful instrument.
Also, if they aren't already installed, I'd recommend you get some socket savers. Tube Depot has them.
Great Units--Congratulations on your investment.
http://www.desmith.net/NMdS/Electronics/Hickok/Hickok 539C Calibration V4.1.pdf
I think there are enough similarities to your unit to be helpful. I used an Oscilloscope to balance the rectifier output pulses on my Western Electric KS-15750-L1 tube tester made by HICKOK which is based on the 539 models.
Balance Pot:
In addition to the usual stuff, my unit allows me to measure plate, cathode and screen grid currents.
If you really want to learn how a tube works, fix a tube tester. It took a while to figure it out and calibrate it properly but it's a useful instrument.
Also, if they aren't already installed, I'd recommend you get some socket savers. Tube Depot has them.
Great Units--Congratulations on your investment.
tube-a-lou
Addicted Member
Thanks for that, I do have the service manual for the 600A and I could go thru some of the test's
but the ones with the scope I can't do, don't have one of those so it will be partly tested and hoping
that will be enough to get it going. I did fix the roller the biggest problem was age and loose parts
that had to be secured on, still have to work on it it's a little off but it works.
but the ones with the scope I can't do, don't have one of those so it will be partly tested and hoping
that will be enough to get it going. I did fix the roller the biggest problem was age and loose parts
that had to be secured on, still have to work on it it's a little off but it works.
ferninando
Lunatic Member
All I know is, that in spite of any negativity of the 600A,
I really like mine alot. much easier to lug around and works just as good as my 533.
Mine too was used but well cared for. the case did nit even have any tares or rip ups
and the front panel is very nice and clean and the scrool works.
I think U did good tube-a-lu
I really like mine alot. much easier to lug around and works just as good as my 533.
Mine too was used but well cared for. the case did nit even have any tares or rip ups
and the front panel is very nice and clean and the scrool works.
I think U did good tube-a-lu
arts
Addicted Member
The 600A is an excellent machine Fern,and nothing will ever change that. When anyone starts spouting off otherwise,I don't pay them much mind
(some will say I don't have much to spend,but that's another matter entirely!)
