Unless you have to move the IF osc around, why not use a crystal?
With a 5 KHz PLL reference, you might have some sidebands from this.
What is the cutoff of the loop filter?

R

John Wilkinson wrote:
Hi,
OK I have a 45MHz crystal filter for my first IF.
The first LO ranges from 45-75MHz.
To test I am using a 45.455MHz LO, which is a pll design.
When I connect up the LO to the mixer, with no input signal I get a -80dBm
level out of my IF stage!!
The PLL is clocked off 1MHz ref divided down to 5KHz. The 1MHz ref is a TTL
signal. Could this be the cause of the problem, and if so how do I get
around it?

Thanks,
John.