Matched Pair of General Electric 12BY7A NOS Vacuum Tubes (Identical USA Production Lot)

For the demanding technician and the dedicated amateur radio enthusiast, consistency is everything. We proudly offer a matched pair of General Electric 12BY7A NOS vacuum tubes—a unique opportunity to acquire one of the most sought-after RF driver tubes, together with an identical spare from the same production lot.
Both tubes are genuine New Old Stock (NOS) units manufactured by General Electric in the USA, making them an excellent choice for maintaining consistent performance in classic HF transceivers or keeping an exact replacement on hand for future service.

Both tubes are marked with the 188-5 factory code. Under the U.S. EIA manufacturer identification system, 188 confirms genuine General Electric production, a manufacturer renowned for producing some of the most rugged, low-noise vacuum tubes of the era. The “5” indicates that both tubes were manufactured during the same production run, providing excellent consistency in manufacturing conditions. Whether you’re restoring two classic transceivers or simply want an identical spare for years of reliable service, this pair represents an outstanding long-term investment for the serious radio amateur or vintage equipment collector.

Superior GE Engineering
As indicated by the markings on the tubes, General Electric qualified these valves for use under the 12BY7A, 12BV7, and 12DQ7 designations. They are direct, universal replacements for equipment specifying any of these tube types, providing broad compatibility while maintaining the high manufacturing standards for which GE is renowned.

Compatibility with Classic Transceivers
The 12BY7A is the heart of the RF driver stage, providing the excitation signal that drives the final power amplifier (PA) tubes in many legendary amateur radio transceivers, including:

• Kenwood: TS-520, TS-530S, TS-820, TS-830S.

• Yaesu: Compatible with the FT-101 series (all tube-based versions), FT-901DM, and FT-902DM.

• Drake: T-4X series transmitters and TR-3 / TR-4 transceivers.

Technical Specifications (Per Tube – Datasheet Reference)

• Type: Sharp-Cutoff Amplifier Pentode.

• Base Type: B9A Noval (9-Pin Miniature).

• Heater Voltage: 12.6 V (AC or DC).

• Heater Current: 0.3 A.

• Maximum Plate Dissipation: 6.5 Watts.

• Transconductance: High-gain design, typically rated at 12,000 µmhos.

(FAQ)

1. Most radios use only one 12BY7A. Why buy a pair?
Purchasing a pair from the same production lot ensures that, if you ever need to replace the RF driver tube, you’ll install a valve with virtually the same electrical characteristics and gain curve as the original. It is the best way to maintain a consistent запас of replacement tubes for long-term ownership, restoration, and preservation of collectible vintage equipment.

2. What does the “188-5” code on the tube actually mean?
The “188” is the EIA (Electronic Industries Association) manufacturer code assigned to General Electric in the United States, identifying the tube as genuine GE production. The “5” is a factory date/production lot code. Finding vintage NOS tubes in their original boxes that share the exact same lot code is uncommon and indicates that both tubes originated from the same manufacturing run, making them an ideal matched pair for collectors, restorers, and long-term spare inventory.

3. Are these General Electric 12BY7A NOS tubes a matched pair?
These tubes are offered as a Same Date Code Pair, meaning both were manufactured during the same General Electric production run. Unlike final output tubes such as the 6146B, which often require closely matched electrical characteristics because they operate together in the power amplifier stage, the 12BY7A is typically used as a single RF driver tube. Therefore, a precision current-matched pair is generally unnecessary. Both tubes have been professionally tested on a tube tester to verify strong emission, proper transconductance, and the absence of shorts, ensuring reliable performance and making them an excellent choice for use and as an identical long-term spare.