SOLD - RARE 6SN7GT / VT-231 Raytheon Black Plate Military Tubes

You will revive the exact tubes pictured in the photo.

🏭 Manufacturer Authenticity

The construction screams true Raytheon U.S. production:

Plate Structure

• Thick long black plates

• Smooth plate surface (not ribbed like Sylvania)

• Slightly rounded plate edges

• Clean rectangular cutouts

Classic Raytheon look.

⚓ UTS Anchor Stamp

The anchor + “UTS” marking indicates:

• U.S. Navy contract production

• Likely early-to-mid 1950s

• Military screened

That’s a positive sign — not a red flag.

🔬 Internal Build Quality

These show:

• Heavy support rods

• Tight mica spacing

• Clean getter flash

• No obvious plate warping

• Strong vacuum (flashing looks intact)

They look healthy structurally.

🧠 Dating Estimate

Based on:

• Black base

• Long black plates

• Military labeling

• Getter style

I’d place these roughly early to mid 1950s Raytheon production.

These are not late 60s consumer tubes.
These are real deal mid-century military pieces.

🎵 Sonic Character (Classic Raytheon Long Plate)

If they test strong, expect:

• Big dimensional midrange

• Slight warmth

• Good bass weight

• Smooth but not overly bright top end

• Strong center imaging

Raytheon long black plates often have:

• A slightly “bold American” presentation

• More punch than Sylvania

• More drive than RCA grey glass

• Not as lush as early Tung-Sol round plate

They can sound very authoritative in the right circuit.