Alignment is easy, adjust the 1K0 preset pot with a 10.7 MHz input, whilst watching DC output of the filter (AF out). At some setting the PLL will be in-lock and the voltage will follow the movements of the control. Set the control for 1.8 - 2.2 volts DC.
This circuit can also be added to commercial HF receivers and transcievers not equiped with FM mode. Additional RF filtering may be necessary in the AF output if there is little or non in the following AF amplifier although this may only be necessary at 455KHz.
Have fun with QRP de Harry Lythall - Lunda, Sweden.
Dont forget to visit my messageboard if you have any questions about this or any other project. I always look forward to receiving feedback, positive or negative. You do not have to register to post messages.
Very best regards from Harry Lythall
SM0VPO (QRA = JO89WO), Märsta, Sweden.
EA/SM0VPO (QRA = IM86BS), Nerja, Spain.