[time-nuts] Re: measuring tiny devices

[Lux, Jim]

On 5/26/22 8:18 AM, Bob kb8tq via time-nuts wrote:
> Hi
>
> The real answer to the problem is to dig into the bowels of 1940’s electronic craft.
> There are various methods for setting up an L/C filter. You short this / open that sweep
> to find a dip or a peak. You move it to the “right” place. Just what you do depends
> very much on the filter design. Many L/C’s got done this way or that way simply
> because they would fit a known alignment method.
>
> While it all sounds very cumbersome and obscure it actually isn’t. Long ago I stumbled
> upon a gal setting up very complex L/C IF filters this way. The display gyrated this way
> and that way as she did this or that. I don’t think it took her more than a minute to get
> the whole thing set up….. to this day, I’m amazed by how fast she was.
>
> Do I have any useful links to actually read up on  this magic? … sorry about that.
>
> Bob

There are actually computer driven screwdrivers to do tuning on cavity 
filters. The operator puts the screwdriver to each cavity in turn. The 
filter is hooked up to a VNA with a computer that runs the scripts..