1944 Sylvania JAN-CHS 6SN7GT VT-231 – 2-Hole Black T-Plates, Bottom Foil Getter – Amplitrex Tested

Authentic 1940s Sylvania JAN-CHS-6SN7GT / VT-231 dual-triode vacuum tube, made in the USA to U.S. military specifications.

This early Sylvania VT-231 presents very well, with clear glass, highly legible white military markings and desirable two-hole black T-plate construction. It has been comprehensively tested on an Amplitrex AT1000 and is ready for use in compatible vintage audio equipment.

TESTED AND VERIFIED

Triode 1:

• 86% emission
• 92% transconductance

Triode 2:

• 88% emission
• 100% transconductance

Both triode sections tested within the Amplitrex’s good operating range. The transconductance readings are within 8% of one another.

It also passed checks for:

• Shorts
• Leakage
• Gas
• Noise
• Microphonics

CONSTRUCTION AND MARKINGS

• Two-hole black T-plates
• Bottom foil/pan getter
• Clear glass
• Black 8-pin octal base
• JAN-CHS-6SN7GT and VT-231 military markings
• Intact center guide key
• “4D” and “SC 966 A” base markings
• Made in the USA

The construction and markings are consistent with Sylvania’s 1940s WWII-era VT-231 production.

The Sylvania VT-231 is sought after by tube-audio enthusiasts for its reputation for articulate detail, open presentation and natural tonal character. The 6SN7GT was widely used in vintage preamplifiers, headphone amplifiers, line stages, phase inverters and power-amplifier driver circuits.

Typical 6SN7GT specifications include a 6.3V/0.6A heater, amplification factor of 20 and nominal transconductance of approximately 2,600 µmhos per section.

CONDITION

Used vintage tube with clear glass, excellent printing and normal age/insertion evidence on the pins. The emission readings differ between sections and are disclosed exactly as tested; the tube is not represented as perfectly balanced. No original box is included.

Important: this is an original-specification 6SN7GT/VT-231, not the later higher-voltage 6SN7GTA or 6SN7GTB. Please verify compatibility with your equipment.

You will receive the exact tube pictured. It will be carefully wrapped, boxed and protected for shipment.

Inventory: tmp-7-2-99497068