Scanner Crystals

Bearcat Crystal Formulas

Bearcat Low-band

• Third Overtone
• Receive frequency + 10.8 MHz = crystal frequency
• HC25/u holder

Bearcat High-band

• Third Overtone
• Receive frequency - 10.8 MHz / 3 = crystal frequency
• HC25/u holder

Bearcat UHF-band

• Third Overtone
• Channel frequency - 10.8 MHz / 9 = crystal frequency
• HC25/u holder

Regency/Radio Shack (Realistic) Crystal Formulas

Regency & Radio Shack (10.7 MHz IF) Low Band

• Third overtone
• Receive frequency + 10.7 MHz = crystal frequency
• Series resonance - 450Hz
• HC25/u holder

Regency & Radio Shack (10.7 MHz IF) High Band

• Third overtone
• Receive frequency - 10.7 MHz / 3 = crystal frequency
• Series resonance - 450Hz
• HC25/u holder

Regency UHF-band

• Third Overtone
• Receive frequency - 10.7 MHz / 9 = crystal frequency
• Load capacitance 18pf
• HC25/u holder

Radio Shack (Realistic) UHF

• Triple conversion
• Receive frequency - 44 MHz / 9 = crystal frequency

Crystal Markings

77 means it was made for a Radio Shack Pro-77 and uses a 10.7 IF.

External Links

• Ken's Electronics Crystal Reference Page