[old_tv_nut]

What circuit are the taped cans in?

For relatively low frequency circuits where the stray capacitance is not significant, it would be possible to include a capacitor inside the coil assembly and automatically pre-tune it during the assembly manufacture, before installing on the printed circuit.

Motorola's coil plant made some pre-tuned assemblies, but I always thought they still had to be adjusted after installation in the chassis. I used eight pretuned coils (IIRC) in our redesign of the CBS video film player (EVR), at frequencies around 900 KHz and 1.8 MHz, [linear-phase chroma pilot and chroma subcarrier filters] but they definitely had to be touched up in the final product. This was due to the differences in strays between the winding machine and the final product. It would have been possible to tune samples in the final product and then have the winding machine duplicate the tuning, but it was not worth it because the printed circuit might be changed at some time (material or layout) and change the strays.