Apr 2003, in the midst of the SARS epidemic, saw
me on a plane to Beijing and from there 1hr by car
to Tianjin. Transportation provided by Opera/Consonance.
Liu of Opera (not to be confused with Mr Liu of
TJ tube factory) came along as tour guide. Mr Liu
met us and we got straight down to business the
usual way in China: lunch. The visit started with
a meal at a famous Tianjin seafood restaurant. Fish
steaks braised in Coke (the drink) is Tianjin's
signature dish. The city is on the northern coast
of China. People in this place are super-friendly,
a trait of the Tianjin populace according to Liu.
on to the factory, a new facility since last summer.
We were required to wear plastic booties since
everything is super clean. We started in Mr Liu's
office where he has a display of his creations.
The factory is a private enterprise (no state
involvement) and the owner, Mr. Liu is a veteran
of the tube industry having worked many years
for the Beijing Tube Factory. He graduated from
university in 1955 in the field of vacuum tube
technology and holds a number of QC patents in
that field. He has previously produced CRTs for
NEC. Last October he visited my office in Hong
Kong and I showed him a 6N11 military tube that
is known locally to be an excellent sounding equivalent
to a 6922. He was quite excited to tell us that
the tube was his creation for the military, the
only true frame grid made in China and one of
the most difficult tubes he ever put into production
at BJ tube factory.
factory is smallish with about a dozen workers,
most of whom are old, highly skilled workers from
the tube industry. The specialized machines you
see in the pictures were made by Mr Liu.
sample of the products coming out of the factory.
Up until now there has been a WE flavour to the
lineup but if you look closely you can see some
future products that aren't WE.
and Liu. The factory is the child of Mr Liu on
the left. The baby-faced Liu on the right was
my tour guide and the engineer/audiophile ('feverish
friend' in Chinese) behind DIYHFS kits and Opera
products. The machine between them strings the
filament on it's frame.
parts worked on inside this 'clean box' to reduce
possibility of contamination, and preparation
electrolytic bath to provide the correct chemistry
for individual parts.
parts are fitted, the bottom is heated and shaped
for insertion of inner glass component that the
leads feed from.
the inner glass piece is formed and fitted,
trip to the gas jets and then the fun part, flashing
followed by a trip through this little Frankenstein
device which completes the evacuation.
each stage of production tubes are processed in
these vacuum and heating ovens to eliminate trace
gases and keep the temperature in working range.
the ultrasonic baths, but none were here at the
the 'aging' room. More plate glow. Somewhere in
between the bases were attached; never saw that
is Mr Liu at the control console (he built from
scratch) developing a new tube (PX25). Each electrical
parameter in individually controlled. Well we've
been pressing for a 45. I saw the way he does
it: RCA data sheet and official plate curves on
the desk before him, Tektronix 570 curve tracer
(thanks Ed Sawyer) showing the actual plate curve
he's getting. Not quite the same yet so another
prototype is made with mechanical adjustments
to the internal parts and try again. Many development
cycles/prototypes before the original spec is
achieved. Mr Liu said that the 45 has been a tough
one. Also in the works is this PX25 mesh plate
(almost done), and an 845.
is Mr Liu and me. I was sure I had more hair than
him. Must be the lighting.
that's the end.