K31-11-3 Silver Mica Capacitors – 750pF to 0.01uF, 500V – Lot of  50 pcs – USSR NOS – Precision RF Components

Product Description:
This listing is for a lot of 50 silver mica capacitors of Soviet origin, type K31-11-3, with capacitance values ranging from 7500pF to 0.01uF, rated at 500V DC. These components are new old stock (NOS) and were originally manufactured for use in military, aerospace, and high-reliability RF circuits in the USSR.

Technical Specifications:

• Type: Silver Mica Capacitor
• Model: K31-11-3
• Capacitance Range: 750pF to 0.01uF
• Capacitance Tolerance: ±5% (standard); tighter grades available depending on batch
• Rated Voltage (UR): 500V DC
• Dielectric Type: Natural Mica with silver electrode plates
• Operating Frequency Range: Up to 100 MHz and beyond (excellent Q at high frequencies)
• Temperature Coefficient: Class I; typically ±30 ppm/°C or better
• Operating Temperature Range: –60°C to +125°C
• Insulation Resistance: >10 GΩ at 25°C
• Dissipation Factor (tan δ): ≤0.001 at 1 MHz
• Lead Type: Radial leads, tinned copper
• Body Style: Molded rectangular epoxy case
• Package Dimensions (approx.):
• Length: 17–19 mm
• Width: 17–19 mm
• Lead spacing: ~13-15 mm
  (Dimensions may vary slightly depending on capacitance value)
• Markings: Each unit is marked with value code and type (e.g., K31-11-3 3300p)

Features:

• Ultra-stable performance over time and temperature
• High Q factor – low energy loss at RF and high-frequency use
• Non-inductive construction for precision circuitry
• Hermetically sealed in resin for moisture and environmental protection
• Excellent aging characteristics (negligible drift over decades)
• Compliant with Soviet military standards (analogous to MIL-C-5 in the West)

Applications:

• RF/microwave circuits
• Oscillators, filters, resonant circuits
• Audio crossovers and tone control
• Instrumentation and measuring devices
• Tube radio and vintage equipment restoration
• Aerospace, telecommunications, and military-grade electronics

Condition:
New old stock (NOS) – unused, clean, and tested for continuity and integrity. Stored in dry military warehouse conditions.

What's Included:

• 50 x Silver Mica Capacitors K31-11-3 (values from 750pF to 0.01uF)