One Cunningham 71A Power Triode Tube
Used – Excellent Condition (1930s Production)
Satisfaction Guaranteed
Etched (Engraved) Black Base
Globe / Balloon / S-Type Envelope
Date Code: E 4. = 1930s
Includes White Tube Box
Appearance: Well-Preserved Vintage Example
Inv. # 18-3 77948130
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🧪 TEST RESULTS (Triplett 3444)
• Minimum Good Gm: >850
• Average New Gm: ~1700
• This Tube: 1800 Gm
• Plate Current: 17.6 mA
• Strong Emission • Balanced Triode Sections
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🧠 HISTORICAL CHARACTER
• Classic **directly heated triode**, designed for use in early audio and radio gear
• Globe (S-shaped) envelope and etched base signify **pre-WWII RCA-era craftsmanship**
• Collectible and functional — ideal for restoring early single-ended triode (SET) amps, vintage radios, and intercom circuits
• Highly regarded for its **warm, articulate tone** and **stable plate characteristics**
🎯 The 71A is prized by enthusiasts seeking **authentic triode tone from America’s golden age of tube manufacturing.** This one is fully verified and tested with confidence.
Ships fast, packed securely, and handled with care throughout storage.
This item is sold As-Described
This item is sold As-Described and cannot be returned unless it arrives in a condition different from how it was described or photographed. Items must be returned in original, as-shipped condition with all original packaging.Learn More.
| Listed | 2 years ago |
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| Condition | Excellent (Used) Excellent items are almost entirely free from blemishes and other visual defects and have been played or used with the utmost care.Learn more |
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