Sweeping the XR2206

I hope you can help me...I found you from an old message on a google newsgroup 'sci.electronics' regarding sweeping the XR2206. I am having problems getting the XR2206 to sweep with a ramp voltage. I have the XR2206 configured as per fig10. in the datasheet, and I want to sweep from around 975kHz to 1025kHz. ( centre frequency 1MHz). I am sweeping with ramp signal at 33Hz, +/- 2 volts centred on zero, but when i apply the ramp voltage to resistor at pin 7, the ramp is offset by about 1 volt and is distorted. Is this normal? I am only getting a couple of MHz of sweep, way lower than my goal... What am I doing wrong? Any ideas