BH1417F VCO Tuning Issues

[mikalcarbine]

Hey forum!

I've created a Bluetooth FM transmitter for my senior project by combining a WT32 Bluetooth Module with an FM Transmitter based off of the BH1417F and the circuit seen here: http://electronics-diy.com/BH1417_PLL_Stereo_FM_Transmitter.php

I've fired the FM transmitter up for testing. Originally I set the frequency to 106.7 and tuned the variable inductor get a voltage roughly above 2v at the first test point (the point between the two 3.3k resistors and the 2.2nF cap). However when I switch to the opposite side of the FM band, ie 87.9, I am required to readjust the inductor the complete opposite way to achieve stable operation. Through some research I found these threads:

http://www.electronics-lab.com/forum/index.php?topic=11519.msg62890

http://www.electronics-lab.com/forum/index.php?topic=10786.msg61621#msg61621

The second link is most important and on reply 2 it speaks of the exact problem I am having, however the attachment of the circuit fix is no longer valid :( Can anyone help me out or guide me in the right direction with this one? I'd like to be able to have all of the available FM band at my disposal without having to readjust the inductor every time.

[audioguru]

I think the BH141x ICs are designed for four low frequencies or four high frequencies.
So you must re-adjust the tuned circuit to have one or the other.

[mikalcarbine]

That seems so pointless/such a nuisance. Does anyone have information on a dual section VCO that might fix this?

[mikalcarbine]

Any other help?