• Change R76 (3.3k) to a 1k (located near mike socket)
• Change R43 (10 Ohm) to a 2.7 Ohm.
• Change R108 (1 Ohm) to a .47 Ohm.
• Replace stock final with a 2SC1969 transistor.
• Re-tune coils L10,L9,L8 for maximum forward power.

PARTS NEEDED: 1- 220uF (16 to 25 volt) electrolytic capacitor. 1- 100 to 200 Ohm resistor. (1/4 to 1/2 watt)

1. Make sure your radio is peaked out.
2. Unsolder JP6 near final.
3. In JP6 holes, solder the 220uF capacitor. (negative side of cap. faces final)
4. On the solder side of the board, solder the resistor across the 220uF capacitor. You can use different resistor values to get the desired dead-key.

• VARIABLE POWER

1. Find the two wires that are attached to the RF gain control, follow them to the PC board and UNSOLDER them.
2. Solder in a jumper wire from where you removed the wires on the board. This will restore receive.
3. Place the two wires from the RF gain control in your mod kit by soldering one wire to each of the 220uF capacitors leads.

• AM LIMITER (D-11)
• Change R58(10 Ohm) to a 2.7 Ohm.
• Change R123(1 ohm) to a .47 Ohm.
• Re-tune L14,L13,L12 for maximum forward power.

1. Remove final and replace with a 2SC1969 transistor.
2. Remove R123 and replace with a jumper.
3. Replace C58 with a 180pF capacitor.
4. Re-tune coils.

CAUTION!!! I do not know if both of these power mods can be done at the same time!!!

• The instructions are the same as the Cobra 25 above,EXCEPT the following.
  
• Unsolder JP36 instead of JP6.

• Remove TR24 (modulation block)
• Change R126 (10k) to a 2.2k
• Change R124 (10k) to a 4.7k
• Re-tune L37 and L38 for maximum AM forward power
• AM POWER: VR10
• SSB POWER: VR11

• Cut D14 (modulation block)
• Locate the 2.7 ohm resistor in front of the final bias resistor(15 Ohm w/RF bead) and change it to a .47 Ohm. (DO NOT change the 15 Ohm resistor!!)
• Re-tune L9,L6,L5,L4 for maximum forward power

• VR5 or cut D9 (modulation block)
• Replace R76 (3.3k) with a 1k.
• Replace R43 (10 Ohm) with a 2.7 Ohm.
• Replace R108 (1 Ohm) with a .47 Ohm.
• Re-tune coils L13,L10,L9,L8 for max forward power.

• VR14 or cut R249 (modulation block)
• Remove TR32
• Replace R174 (10k) with a 1 K
• Replace R187 (10k) with a 1 K
• AM POWER VR13
• SSB POWER VR12

• Remove TR32 (modulation block)
• Replace R174 (10k) with a 2.2k
• Replace R187 (10k) with a 2.2k
• Modulation VR14 (inoperable if TR32 is removed)
• AM Power VR13
• SSB Power VR12 (inoperable if TR32 is removed)

• VR1 AM/FM "S" meter
  
• VR2 SSB/CW "S" meter
  
• VR3 SSB SQUELCH
  
• VR4 AM SQUELCH
  
• VR5 FM DEVIATION
  
• VR7 CARRIER BALANCE
  
• VR8 RF POWER METER
  
• VR10 FINAL BIAS
  
• VR11 DRIVER BIAS
  
• VR12 SSB POWER(ALC)
  
• VR13 AM POWER
  
• VR14 MODULATION
  
• VR16 CW TONE LEVEL
  
• VR20 FINAL BIAS
  
• VR803 AM LOW TX POWER
  

• Remove TR24 (modulation block)
• Replace R126 (10k) with a 2.2k.
• Replace R124 (10k) with a 4.7k
• Re-tune coils L37 and L38 for maximum forward swing on AM mode.
• AM POWER VR10
• SSB POWER VR11

• Remove TR32 (modulation block)
• Replace R99 (10k) with a 2.2k
• Replace R94 (10k( with a 2.2k
• Re-tune coils L36,L37 for maximum forward AM power.

VARIABLE ADJUSTMENTS

• AM POWER: VR6
• SSB POWER: VR7
• RX METER: VR1
• TX METER: VR10
• SQUELCH: VR2
• TX FREQ.: VR3
• CARRIER BAL: VR5
• DRIVER BIAS: VR8
• FINAL BIAS: VR9
• MODULATION METER: VR12

• VR12 or Cut R131(modulation block)
• Remove TR24
• Replace R126 (10k) with a 2.2k
• Replace R124 (10k) with a 4.7k Re-tune coils L37,L38 for maximum forward power.

• AM POWER: VR10
• SSB POWER: VR11
• AM SIGNAL METER: VR1
• SSB SIGNAL METER: VR2
• SQUELCH: VR3
• CARRIER BALANCE: VR4
• TX FREQ.: VR5
• TX METER: VR6
• MODULATION METER: VR7
• FINAL BIAS(50 Ma): VR8
• DRIVER BIAS(25 Ma): VR9

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