The Hewlett Packard 70100A is the power meter module in the HP 70000 modular test system. This post will document a problem common to three 70100A units I have recently restored.

As part of the restoration process, I opened the modules to perform a visual inspection. What I found under the outer cover was this:

70100A PS CPU Board Solder Side Overview before repair

HP 70100A PS CPU Board Deteriorated Rubber Pads

HP 70100A PS CPU Board Deteriorated Rubber Pads

HP 70100A PS CPU Board Deteriorated Rubber Pads

HP 70100A PS CPU Board Deteriorated Rubber Pads

The rubber spacer pads between the circuit boards and the outer metal cover had deteriorated to the point of liquifying and running down board via gravity. All the pads in the three units I examined were afflicted to some degree. Several years ago, I documented a similar phenomenon … Read More »

The Cubic 3250 VLF-HF receiver is a 10kHz – 30 MHz DSP based radio receiver with 51 IF bandwidths and 7 receive modes. It falls into the category of professional/military grade equipment and the build quality certainly reflects this. According to Fred Osterman’s book, “Shortwave Receivers Past and Present, 3rd Ed.”, it was manufactured from the mid 1990s until at least 1998 (possibly later). I have found that the audio recovery and readability of this receiver is outstanding.

As both of my units were made in 1995/96, they are 25 years old and likely have thousands of hours of use. So I elected to replace all the electrolytic capacitors in the power supply with (arguably) an abundance of caution.