Hickok 600A

tube-a-lou

Addicted Member
Hi all,
Is it worth buying one of these, I've seen one and know how good they are,
I'm getting more into tubes and it would be great to get one and fix it up, if
possible.

Thanks
 
I've had a 600a on my bench for the past 25 years and it is a good tester. They are easy to calibrate and instructions available on the internet. I also have a Hickok 539B which is a great tube tester, but unfortunately the price for one of them has gone out of sight in recent years.
 
Good,solid and reliable tester. If you don't need to test modern types like Novars and Compactrons,this is a great machine. About a zillion years ago I made an adapter from an old tube socket for mine so I could test 7868's:naughty:
 
I had a 600A, my first tester. I dumped it as soon as a 539 I could afford became available. And you know what? I kind of wish I'd just stayed with the 600A after I got over the cool factor of the 539. Don't get me wrong, the 539 is a great machine but, so is the 600A. Handy size and any tube data not on the roll chart you can find elsewhere. And as mentioned above, you can make an adapter if need be. I say go for it!
 
I recently picked up a 600A as well... sitting in my garage waiting to be re-capped and calibrated (I also plan to get rid of the mercury rectifier, opting for a regulated solid state replacement). Nice little unit, and adapters are easy to make :)

And if you can't find "tube data" for a particular tube... who cares? If you understand how the tester works, you can come up with your own settings and just read the gm numbers and make your own assessment based on the tube's data sheet and your tolerance for ... uh... tolerance :)
 
I recently picked up a 600A as well... sitting in my garage waiting to be re-capped and calibrated (I also plan to get rid of the mercury rectifier, opting for a regulated solid state replacement). Nice little unit, and adapters are easy to make :)

And if you can't find "tube data" for a particular tube... who cares? If you understand how the tester works, you can come up with your own settings and just read the gm numbers and make your own assessment based on the tube's data sheet and your tolerance for ... uh... tolerance :)

Hickok had an official conversion from tube rectification (both the 83 & 5Y3) to solid state that allowed the unit to retain it's calibration and accuracy. I've got the paperwork here somewhere for my Marconi MU-101 (Canadian military Hickok built under license) that I can try to find.I'm hoping somebody else finds it first though.......
 
Meh,there's nothing wrong with a tube rectifier,mercury or vacuum type. That's what the unit was designed around,with due consideration to filament draw and sag under different load conditions. Upset that and you've upset the whole applecart. Heat? How hot do a pair of essentially unloaded rectifiers get? About equal to a 25 watt bulb. It's not like we're doing life tests on 6550's.Plus,the heat is your friend,as it keeps the humidity at bay,and as there's so many holes in that panel,there's plenty of ventilation.
Personally,I'd just leave well enough alone....But I would verify the calibration.

My 600A and 539 often run 8 hours or more a day,and have done so for decades.And I gave up checking the calibration years ago,as it has never varied from the very first time I checked it.
 
Done! I went for it, I purchased it and when I receive it I'll post pictures. The seller says it works
It lights up, I hope it's a good thing. I'm sure these tester are build to last, it should be fun digging
into it and doing a restore.
 
Done! I went for it, I purchased it and when I receive it I'll post pictures. The seller says it works
It lights up, I hope it's a good thing. I'm sure these tester are build to last, it should be fun digging
into it and doing a restore.

You scored a good one:)Tons of service and restoration info available on the net,as well as the charts listing every tube it can test. And with a little ingenuity (and some home-made adapters) you can even check later tube types by using the test data from other,similar Hickok machines.Winner!

If the machine was well cared for,you may require very little restoration effort other than cleaning the sockets and switches.One thing you MUST check is that the fuse lamp is the correct type,which is a #49. And get an old (real) one,not a Chinese crapper.Otherwise, you're risking the machines life if you have a mishap.

See this gentleman's site for more info: (manual and charts)

http://www.stevenjohnson.com/hickok/data.htm
 
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Meh,there's nothing wrong with a tube rectifier,mercury or vacuum type.

I don't have a problem with tube rectifiers, per se. But I don't want an item with a big blob of mercury floating around in it in the same workspace that my kids will be using.
 
I need to watch that 6000A video just to make sure my 6000A is calibrated properly.

I don't have a problem with tube rectifiers, per se. But I don't want an item with a big blob of mercury floating around in it in the same workspace that my kids will be using.

There is no blob of mercury. It's mercury vapor, which becomes a kind of flaky coating on the inside of the glass when the tube isn't being heated - and there isn't all that much in there anyway. As long as your kids aren't taking the tester apart and smashing the tubes, there's no danger.
 
Haven't found any official Hickok documentation on that, but there's a fantastic thread here about it: http://www.antiqueradios.com/forums/viewtopic.php?f=8&t=225280&sid=b5ce3f9d0a4447b980d00d02cd45b133

Yes, that is a beautiful discussion, very thorough. This companion piece has additional discussion:
I have not done this for my Hickok 6000A because the rectifier works and the tubes are not horrendously expensive, but it looks easy enough to implement and it does solve the problem of having a rectifier blow because it was stored in one position and then turned on before the mercury redistributed during heating, which takes anywhere from 15 to 30 minutes according to the datasheets.
 
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There is no blob of mercury. It's mercury vapor, which becomes a kind of flaky coating on the inside of the glass when the tube isn't being heated - and there isn't all that much in there anyway. As long as your kids aren't taking the tester apart and smashing the tubes, there's no danger.

Well, technically it condenses to fine droplets and this is why the tube must be pre-warmed if its orientation changes.

I don't know anyone who has broken a tube rectifier. (Except that guy who filed the lawsuits which were dismissed.)

I worry more about broken CFLs, which are more common and more problematic, particularly in enclosed offices.
 
Well, technically it condenses to fine droplets and this is why the tube must be pre-warmed if its orientation changes.

When you consider how many of these machines were used as portables on service calls and in military applications,I wonder just how critical this was and how often it was practiced. And I am one of the guilty ones:cool:
 
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