The choke that comes with the kit should be 5.6 uH.
It does extend the clarifier coverage.
But only if you install it correctly. Putting it in series with the clarifier circuit's varactor diode won't work in this model, or the other 8719 radios that have a trimmer cap for USB, and trimmer coils for AM and LSB.
The setup that puts it in series with one leg of the varactor only works for the 8719 radios that have three coils, one each to trim USB, LSB and AM. The radios with the trimmer cap for USB are different. You have to put the choke in series with the crystal, and *NOT* in series with the varactor diode. This will require a cut in a pcb trace on one leg of the crystal, with the choke soldered across the cut.
It also moves down the center of the channel on the clarifier.
Good chance the radio won't adjust on channel with the clarifier at 12 o'clock with the choke installed. Trimmer won't go high enough.
The typical cheat is to turn the clarifier full clockwise, and set the USB trimmer for 1.5 kHz above the channel center. The trimmer cap will usually be at the end of its travel to do this.
Next, you turn the clarifier down to the channel center frequency, still in USB mode.
Now, pull the knob off the knurl shaft of the control, turn the pointer to 12 o'clock and push it back onto the shaft.
Next, set LSB and AM both for channel center without moving the clarifier. This will give you the same leeway above the channel center frequency that you had before. The remaining travel on the knob as you turn it to the left should get you about one channel down.
About. Your mileage may vary. Might only go down 9 kHz. The radios that have three coils for this and no trimmer cap tend to travel farther down in frequency than this type PLL.
73
