Just finished the rebuild. No LFO ticking now

The de-ticking mod mentioned by Larry needed adjustment though.
The suggested values (33 nF + 68k) smoothed off the square wave too much and caused the sine wave amplitude to vary with sweep rate (which is bad for this circuit).
So I changed the values to 22nF + 10k and that stopped that problem,
I also made some simplifications.
1) I removed the 100nF smoothing caps that I put on the bases of the current-source transistors in the VCOs.
They were no longer necessary with the new layout.
I kept the discharging VCO diodes under the comparator ICs though.
2) The LFO and audio share the same ground (so I could get a nicer layout).
The LFO and audio sections are still star-grounded with respect to each other.
3) I tried removing the 4.7uF Vgg smoothing caps. The circuit works without them, but when I probed the Vgg
pin I saw large clock noise there. So I ended up deciding to use 100nF ceramics instead of the 4.7uF electros.
4) I added more 100nF smoothing caps to the layout. I haven't put any directly between IC supply pins on the bottom of the board.
5) The feedback trimmer was increased from 100k to 200k (so the optimal setting is close to the middle of the trimmer range).
I just need to write all this up now. New build instructions soon.