Uniden Grant Clarifier Modification
This one is similar to the Washington chassis but already has the 11.3258 MHz crystal in the circuit. The 5.6µh choke is needed for the extra range and a super diode in place of the stock varactor diode would give the best range.
The following instructions will open and increase the clarifier range:
- Remove D52
- Remove R148
- Remove R174
- Remove C121
- Jump diode next to D52 location.
- Lift the ground side of D20 and install a 5.6µh choke from the open lead of the diode to ground.
- Follow the red wire from the clarifier control and disconnect it from this point then solder it to ground.
- Follow the orange wire from the clarifier control and disconnect it from this point then solder it to +8 Volts constant (IC4 pin 3).
- Set the clarifier to the 3 O’clock position.
- Connect a frequency counter to TP1 on channel 40.
- In USB adjust CT3 for 35.0075 MHz.
- In LSB adjust L19 for 35.0025 MHz.
- In AM adjust L20 for 35.0050 MHz.
There are other radios that use these chassis and the mods. would be the same. You’ll just have to determine which chassis are the same by looking for commonalties for yourself.