Abstract: A unique RF signal combining/sorting apparatus is disclosed that includes first and second filters each comprised of one or more bandstop/bandpass filters intercoupled by transmission lines. The bandstop/bandpass filters include a shunt inductor or capacitor and a dielectric block having an input electrode plated on its top surface and a hole located at predetermined distance from the input electrode. The dielectric material is preferably a ceramic comprised of BaO, TiO.sub.2 and ZrO.sub.2. The dielectric block is entirely plated with copper or silver except for a portion of the top surface surrounding the hole and electrode and is essentially a capacitively coupled, short-circuited coaxial transmission line. Each of the first and second filters is tuned to pass the frequencies of one signal and attenuate the frequencies of the signal passed by the other. The unique RF signal combining/sorting apparatus can be configured as a multi-signal combiner, multi-signal sorter, or multi-signal combiner/sorter.

Abstract: A depth measurement system particularly suitable for automatically driving a recorder under varying wireline measurement conditions for repeatedly depth recording measurements from borehole tools produces different measurements at generally the same point on the wireline which would correspond if measurement conditions were ideal, but are subject to non-repeatable variations. Accordingly, these signals are automatically utilized to provide a repeatable signal. In one form, the signals correspond to magnetic marks and to incremental movement of the wireline, the latter produced by mechanically coupled devices subject to slippage, variations in circumference, etc. The incremental signals are counted and compared with the number expected for such intervals, a low count indicating slippage or the like and used to provide an appropriate alarm and/or an automatically slippage corrected signal particularly suitable for driving a recorder.