JJ Electronic

JJ Electronic, s.r.o is a Slovak electronic component manufacturer, and one of the world's remaining producers of vacuum tubes. It is based in Čadca, in the Kysuce region of Slovakia.

Most of its products are audio receiving tubes, mainly used for guitar and hi-fi amplifiers. In technical terms, JJ produces triodes, beam tetrodes and power pentodes. Double diode vacuum tubes for full-wave AC-to-DC rectifiers are also produced. JJ also produces electrolytic capacitors for higher-voltage purposes, generally for use in audio amplifiers. JJ also manufactures its own line of high-end audio amplifiers and guitar amplifiers. In 2015, the company sales amounted to EUR 8.5 million and net income came to EUR 3.8 million. Most production is exported to the United States.

History
Before 1989, Tesla was the main Czechoslovak producer of electron tubes. While Tesla vacuum tubes were exported all over the world, and were known for their quality, the company did not survive the change of economic system after 1989 in combination with the downturn in the vacuum tube market. JJ Electronic was founded in 1993 by Jan Jurco, using the old Tesla machinery for the manufacture of vacuum tubes. Eventually, JJ Electronic started to produce its own line of vacuum tubes and electrolytic capacitors, mainly targeted at high-end audiophile and guitar amplifier applications.

Products
Small signal vacuum tubes
 * ECC81/12AT7, dual triode
 * ECC82/12AU7, dual triode
 * ECC83/12AX7, dual triode
 * ECC88/6DJ8, dual triode
 * 12BH7, dual triode
 * 5751, low-noise dual triode
 * EF86, sharp-cutoff pentode
 * 6SN7, dual triode

Power vacuum tubes
 * 300B, directly heated power triode
 * 2A3, directly heated power triode
 * EL34, power pentode
 * EL84, power pentode
 * 6V6, beam tetrode
 * 6L6GC, beam tetrode
 * 5881, beam tetrode
 * 6550, beam tetrode
 * 6CA7, beam tetrode
 * KT66, beam tetrode
 * KT77, beam tetrode
 * KT88, beam tetrode

Rectifiers
 * GZ34, indirectly heated full-wave rectifier
 * 5U4GB, directly heated full-wave rectifier
 * 5Y3, directly heated full-wave rectifier
 * EZ81, indirectly heated full-wave rectifier (noval base)