23 Mar
2006
23 Mar
'06
4:15 p.m.
Not much use I can think of in computing, but in other things quite useful. Most obvious
is gold prospecting,
also used in other metalwork (tempering bath), and in a hobby that will not be named to
remove lead that is stuck to steel.
Also vacuum pumps for home particle accelerators.
23 Mar
23 Mar
4:21 p.m.
From: "Scott Quinn" <compoobah at valleyimplants.com>
Not much use I can think of in computing, but in other things quite
useful. Most
obvious is gold prospecting,
also used in other metalwork (tempering bath), and in
a hobby that will
not be named to remove lead that is stuck to steel.
Also vacuum pumps for home particle accelerators.
If you go back far enough, mercury was used in memories (mercury delay line
in some early British machines).
It is also often used in high speed relays, especially for teleprinter type
circuits - we had some mainframe / telegraph interfaces with mercury wetted
relays in them, in operation, until about 8 years ago
Jim.
6:29 p.m.
On 3/23/2006 at 9:21 PM Jim Beacon wrote:
It is also often used in high speed relays, especially
for teleprinter
type
circuits - we had some mainframe / telegraph interfaces
with mercury
wetted
relays in them, in operation, until about 8 years ago
And as primary cells--mercury cells have a remarkably stable voltage output
over their life.
Cheers,
Chuck
7:05 p.m.
And as primary cells--mercury cells have a remarkably
stable voltage output
over their life.
[Looks sadly at all the classic cameras around here that are more
difficult to use now that ther mercury cells for the exposure meters are
unavailabe. Yes I do know of the work-arrounds...]
IIRC the Weston standard cell is a mercury/cadmium couple.... Although to
be fair a good bandgap voltage reference is accurate enough for anything
I am likely to need, and a lot less hassle.
-tony
7:41 p.m.
On 3/24/2006 at 12:05 AM ard at p850ug1.demon.co.uk wrote:
IIRC the Weston standard cell is a mercury/cadmium
couple.... Although to
be fair a good bandgap voltage reference is accurate enough for anything
I am likely to need, and a lot less hassle.
The Weston cell also has some saturated solutions of mercury and cadmium
salts in addition to the metallic form. Sort of a salt bridge setup. Can
source very little current, though, what, maybe 0.1 ma for the typical 4"
high H-cell? So it's always used as a reference to adjust a primary
source. Of course, if the primary source went kaput, there was nothing to
adjust. In the mills, we'd go around periodically replacing the primary
cells in the chart recorders with those big rectangular black National
Union cells.
My last year on the job was when Honeywell came out with solid-state
voltage references that could actually source some current for their
Electronik series of recorders and controllers. You got rid of the
calibration helipot, primary cells and Weston cells and a bunch of other
miscellaneous parts (recorders would automatically go through a calibration
cycle every few hours). L&N followed somewhat later with their own
version.
AFAIK, the used H-cells just went into the main trash stream.
Cheers,
Chuck
7:44 p.m.
On 3/23/2006 at 9:21 PM Jim Beacon wrote:
I've still got a bunch of telco mercury-wetted sealed DPST reed relays. I
think this wasn't because of current, but rather that the contacts probably
stayed quiet over the life of the equipment.
Cheers,
Chuck
It is also often used in high speed relays,
especially for teleprinter
type
circuits - we had some mainframe / telegraph
interfaces with mercury
wetted
>relays in them, in operation, until about 8 years ago 
23 Mar
23 Mar
6:47 p.m.
On Thursday 23 March 2006 04:21 pm, Jim Beacon wrote:
From: "Scott Quinn" <compoobah at
valleyimplants.com>
I remember seeing those in a book somewhere...
Not much use I can think of in computing, but in
other things quite
useful. Most obvious is gold prospecting, also used in other metalwork
(tempering bath), and in a hobby that will not be named to remove lead
that is stuck to steel.
Also vacuum pumps for home particle accelerators.
If you go back far enough, mercury was used in memories (mercury delay line
in some early British machines). It is also often used in high speed relays, especially
for teleprinter type
circuits - we had some mainframe / telegraph interfaces with mercury wetted
relays in them, in operation, until about 8 years ago
I have a mercury-wetted relay I salvaged out of something or other. Says so
right on it. :-) It also indicates that it should be used in one specific
physical orientation, too.
So the advantage of those is speed?
--
Member of the toughest, meanest, deadliest, most unrelenting -- and
ablest -- form of life in this section of space, a critter that can
be killed but can't be tamed. --Robert A. Heinlein, "The Puppet Masters"
-
Information is more dangerous than cannon to a society ruled by lies. --James
M Dakin
1:54 p.m.
At 06:47 PM 3/23/06 -0500, you wrote:
On Thursday 23 March 2006 04:21 pm, Jim Beacon wrote:
Another advantage is that they won't weld the contacts together or burn
the contacts so they're used in high current applications or in
applications that have big inductive loads. I've replaced the standard
relay in my AC compressor with a large dual contact mercury wetted contact
relay. I pick up everyone of the things that I find and keep them for
applications such as this.
Joe
From: "Scott Quinn" <compoobah at
valleyimplants.com>
I remember seeing those in a book somewhere...
Not much use I can think of in computing, but in
other things quite
useful. Most obvious is gold prospecting, also used in other metalwork
(tempering bath), and in a hobby that will not be named to remove lead
that is stuck to steel.
Also vacuum pumps for home particle accelerators.
If you go back far enough, mercury was used in memories (mercury delay line
in some early British machines). It is also often used in high speed relays,
especially for teleprinter type
circuits - we had some mainframe / telegraph interfaces with mercury wetted
relays in them, in operation, until about 8 years ago
I have a mercury-wetted relay I salvaged out of something or other. Says so
right on it. :-) It also indicates that it should be used in one specific
physical orientation, too.
So the advantage of those is speed? 
6:59 p.m.
----- Original Message -----
From: "Roy J. Tellason" <rtellason at blazenet.net>
To: "General Discussion: On-Topic and Off-Topic Posts"
<cctalk at classiccmp.org>
Sent: Thursday, March 23, 2006 6:47 PM
Subject: Re: Mercury use (WAS RE: hospital surplus)
so
On Thursday 23 March 2006 04:21 pm, Jim Beacon wrote:
> From: "Scott Quinn" <compoobah at valleyimplants.com>
>
> It is also often used in high speed relays, especially for teleprinter
type
> circuits - we had some mainframe / telegraph
interfaces with mercury
wetted
relays in
them, in operation, until about 8 years ago
I have a mercury-wetted relay I salvaged out of something or other. Says right on it. :-) It also indicates that it should
be used in one
specific
physical orientation, too.
So the advantage of those is speed?
I believe (correct me if I am wrong) that a mercury relay is faster then
other mechanical type relays (the ones I used were for switching decent
sized resistive loads), but much slower then solid state relays for doing
the same thing (but the SSR have problems dissipating heat and need to be
actively cooled).
24 Mar
24 Mar
4:05 a.m.
Hi,
Jim Beacon said:
If you go back far enough, mercury was used in memories (mercury delay line
in some early British machines).
Which were developed from the ones used in early radar to eliminate echoes
from fixed objects.
--
Cheers,
Stan Barr stanb at dial.pipex.com
The future was never like this!
24 Mar
24 Mar
4:55 a.m.
On Fri, 24 Mar 2006 00:01:06 +0000 (GMT)
ard at p850ug1.demon.co.uk (Tony Duell) wrote:
Am I the only person to be thinking of EDSAC and its
delay lines here?
My immediate associativity to mercury delay line memory is:
http://www.cs.mu.oz.au/csirac/
--
tsch??,
Jochen
Homepage: http://www.unixag-kl.fh-kl.de/~jkunz/
9:44 a.m.
Tony Duell wrote:
I've got a feeling that the owner of the BCL Susie that we've got to pick up
some time said that there's a mercury delay line in that for some reason...
I don't believe that anyone's mentioned mercury arc rectifiers yet as one
application of mercury (and of course fascinating to watch!). (Did any early
computers ever use them for any reason? Presumably wound transformers were
always the norm, although I'd love an excuse to have a running MAR on display :-)
cheers
Jules
Not much use
I can think of in computing, but in other things quite
Am I the only person to be thinking of EDSAC and its delay lines here?
3:16 p.m.
I don't believe that anyone's mentioned
mercury arc rectifiers yet as one
application of mercury (and of course fascinating to watch!). (Did any early
Nobody's mentioned thyratrons (gas-filled triodes/tetrodes) either. I
suspect the thyratrons used in ring counters, etc, were always inert gas
(and not mercury vapour) ones, does anyone know for sure?
-tony
4:54 p.m.
On 3/24/2006 at 8:16 PM ard at p850ug1.demon.co.uk wrote:
Nobody's mentioned thyratrons (gas-filled
triodes/tetrodes) either. I
suspect the thyratrons used in ring counters, etc, were always inert gas
(and not mercury vapour) ones, does anyone know for sure?
There are small ignitrons that use mercury vapor. There are also ignitrons
that use sodium vapor.
I love the old names for thermionic devices; we've lost that knack for
naming. Any gas-filled thermionic diode is a phanotron, any vacuum-filled
diode is a kenotron. So an 866 is a phanotron (has mercury), but a 5U4 is
a kenotron. A vacuum triode is a pliotron and a gas triode is a thyratron.
Ya gotta love it!
--Chuck
5:53 p.m.
I love the old names for thermionic devices; we've
lost that knack for
I've not heard of half of these...
naming. Any gas-filled thermionic diode is a
phanotron, any vacuum-filled
diode is a kenotron. So an 866 is a phanotron (has mercury), but a 5U4 is
Which reminds me... Didn't one of the Teletypes have a couple of 866s in
the power supply? Anotehr use for mercury in classic computing.
I can't remember. Is the 866 a pure diode, or does it have a trigger
electrode?
a kenotron. A vacuum triode is a pliotron and a gas
triode is a thyratron.
Ya gotta love it!
I guess most of use know 'Rheostat' for a variable resistor. But what
about 'Rheophor' (a conductor, like a length of wire). Or 'Rheotome'
(originally the interupting contact on an induction coil, a mad friend of
mine uses the term for the chopper transistor in an SMPSU).
-tony
6:35 p.m.
On 3/24/2006 at 10:53 PM ard at p850ug1.demon.co.uk wrote:
I can't remember. Is the 866 a pure diode, or does
it have a trigger
electrode?
Diodes, Had 'em in the power supply for my transmitter. There was a
trick where you could use two DPDT switches to turn on the filament and
then HV supplies where no matter which switch was flipped, the filaments
always came on first. Turning on the HV before or at the same time as the
filaments could destroy the things.
Cheers,
Chuck
25 Mar
25 Mar
5:46 p.m.
On 3/24/2006 at 10:53 PM ard at p850ug1.demon.co.uk wrote:
Yes, you're right. I was mis-remembering something I'd read in the RSGB
Teleprinter Handbook (RSGB = Radio Society of Great Britian, roughly the
same as your ARRL). In the edition that I have, it gives a schematic for
the Teletype 19, which uses a pair of thyratrons in the power supply.
There's a comment (references to some ARRL publication) that since these
are expesnive and difficult to find, if you have only one good one, you
can put an 866 rectifier in place of the other one (with a socket change,
etc). The PSU will still regulate correctly with just one good thyratron.
-tony
I can't remember. Is the 866 a pure diode, or
does it have a trigger
electrode?
Diodes, Had 'em in the power supply for my transmitter. There was a 
27 Mar
27 Mar
2:28 a.m.
There was a trick where you could use two DPDT
switches to turn on
the filament and then HV supplies where no matter which switch was
flipped, the filaments always came on first.
You don't need DPDT, just DPST. Wire one pole from each in parallel,
the other pole in series. The parallel-wired ones control the
filament, the series-wired ones the HV. In ASCII graphics:
\ \
\ \
______^ :\_____________________^ :\________ <-- HV switch
: :
\: \:
\ \
______^ \_____ ___^ \________ <-- filament switch
| | | |
| |____________ | __________|
|_________________________|
/~\ The ASCII der Mouse
\ / Ribbon Campaign
X Against HTML mouse at rodents.montreal.qc.ca
/ \ Email! 7D C8 61 52 5D E7 2D 39 4E F1 31 3E E8 B3 27 4B
25 Mar
25 Mar
11:42 a.m.
I love the old names for thermionic devices; we've
lost that knack for
naming. Any gas-filled thermionic diode is a phanotron, any vacuum-filled
diode is a kenotron. So an 866 is a phanotron (has mercury), but a 5U4 is
a kenotron. A vacuum triode is a pliotron and a gas triode is a thyratron.
Ya gotta love it!
Outside the marketing department of General Electric, nobody actually used
these terms, other than thyratron.
William Donzelli
aw288 at osfn.org
6:16 p.m.
I love the old names for thermionic devices;
we've lost that knack for
naming. Any gas-filled thermionic diode is a phanotron, any vacuum-filled
diode is a kenotron. So an 866 is a phanotron (has mercury), but a 5U4 is
a kenotron. A vacuum triode is a pliotron and a gas triode is a thyratron.
Ya gotta love it!
Outside the marketing department of General Electric, nobody actually used
these terms, other than thyratron.
7:08 p.m.
On 3/25/2006 at 11:16 PM ard at p850ug1.demon.co.uk wrote:
Dit anyone other than RCA ever use the term
'Kinescope' for CRT? I
rememebr when I read the service manual for the monitor for my TRS-80
Model 1 (this monitor being a converted RCA portable TV, of course),
wondering what on earth the Kinescope was....
"Kinescope" was used outside of RCA. Actually, "Cathode Ray Tube" is
a bit
too general--e.g., a Crookes tube is a CRT. Besides, haven't we figured
out what "cathode rays" are yet?
I like the old "picture tube" better.
:)
Cheers,
Chuck
26 Mar
26 Mar
12:30 p.m.
On 3/25/2006 at 11:16 PM ard at p850ug1.demon.co.uk wrote:
Right... It's not a term that I've ever seen in an English (as distinct
Dit anyone other than RCA ever use the term
'Kinescope' for CRT? I
rememebr when I read the service manual for the monitor for my TRS-80
Model 1 (this monitor being a converted RCA portable TV, of course),
wondering what on earth the Kinescope was....
"Kinescope" was used outside of RCA. Actually, "Cathode Ray Tube" is
a bit from American) book or manual.
too general--e.g., a Crookes tube is a CRT. Besides,
haven't we figured
out what "cathode rays" are yet?
Yes, but we can't call it an 'electron tube' since that's what you call a
valve (glassfet, whatever). And 'Electron Ray Tube' is another name (at
least here) for that form of indicator commonly called a 'Magic Eye'.
I like the old "picture tube" better.
What, even when it's being used as part of a Williams memory?
[Sorry, couldn't resist ;-)]
-tony
2:06 p.m.
On 3/26/2006 at 6:30 PM ard at p850ug1.demon.co.uk wrote:
Or, in electronics slang, "bottle" or "jug". :)
'Bottle' is slang for any glass vacuum device (including valves and
CRTs). I've seen the convention that 'valve' is a set of electrodes
including the cathode and anode while 'bottle' is a glass envelope that
contains one or more valves. That is, a 12AX7 (ECC83, etc) is one bottle
but two (triode) valves.
-tony
I like
the old "picture tube" better.
What, even when it's being used as part of a Williams memory?
[Sorry, couldn't resist ;-)]
4:02 p.m.
On Sunday 26 March 2006 12:30 pm, Tony Duell wrote:
Yes, but we can't call it an 'electron
tube' since that's what you call a
valve (glassfet, whatever). And 'Electron Ray Tube' is another name (at
least here) for that form of indicator commonly called a 'Magic Eye'.
Now I sure wouldn't mind getting my hands on some of _those_...!
There seem to be all sorts of VFDs in audio gear these days but even the ones
designed for level indicators still use discrete steps, making them
"digital", while those old 6E5 tubes (and similar) were most definitely
"analog". :-)
Anybody have any of those kicking around?
--
Member of the toughest, meanest, deadliest, most unrelenting -- and
ablest -- form of life in this section of space, a critter that can
be killed but can't be tamed. --Robert A. Heinlein, "The Puppet Masters"
-
Information is more dangerous than cannon to a society ruled by lies. --James
M Dakin
24 Mar
24 Mar
5:54 p.m.
The earliest electrical use of mercury that I can think of is the so-called
(I think) "mercury tube". A quantity of mercury is sealed inside of an
evacuated glass tube. When the tube is shaken, flashes of light (from the
ionized mercury vapor) can be seen.
This is at least an 18th century discovery and may go back to the 17th
century. Because the vacuum was obtained by using the empty space at the
top of a mercury barometer, the phenomenon was called "barometric light".
I also believe that Edison evacuated early models of his incandescent lamp
using mercury and the barometric effect.
Cheers,
Chuck
25 Mar
25 Mar
12:29 p.m.
On Friday 24 March 2006 03:16 pm, Tony Duell wrote:
No, but I am currently in the process of collecting datasheets on tubes and
am running into some really amazing stuff so far. A somewhat earlier version
of what I've got is at http://yourpage.blazenet.net/rtellason/tubes.html if
anyone wants to take a look. I'm currently adding a *lot* more stuff to that
page, but it'll be a bit yet before I get around to uploading the new
version.
--
Member of the toughest, meanest, deadliest, most unrelenting -- and
ablest -- form of life in this section of space, a critter that can
be killed but can't be tamed. --Robert A. Heinlein, "The Puppet Masters"
-
Information is more dangerous than cannon to a society ruled by lies. --James
M Dakin
I don't
believe that anyone's mentioned mercury arc rectifiers yet as one
application of mercury (and of course fascinating to watch!). (Did any
early
Nobody's mentioned thyratrons (gas-filled triodes/tetrodes) either. I
suspect the thyratrons used in ring counters, etc, were always inert gas
(and not mercury vapour) ones, does anyone know for sure?
6674
days inactive
6678
days old
29 comments
12 participants
participants (12)
-
ard＠p850ug1.demon.co.uk -
aw288＠osfn.org -
cclist＠sydex.com -
compoobah＠valleyimplants.com -
jim＠g1jbg.co.uk -
jkunz＠unixag-kl.fh-kl.de -
julesrichardsonuk＠yahoo.co.uk -
mouse＠Rodents.Montreal.QC.CA -
rigdonj＠cfl.rr.com -
rtellason＠blazenet.net -
stanb＠dial.pipex.com -
teoz＠neo.rr.com