Hi,
I've a compatibility problem of my HP8558B S/N 1707A03258 (low S/N) Spectrum Analyzer plug-in with my HP853A display main frame. Only using it in analog mode, all seems to operate OK. I know that HP in the past released a modification kit for 8558B plug-in with S/N 2145 and lower, HP P/N 00853-60058 including some components plus wire connections to obtain full compatibility between the 8558B low S/N and 853A display. Unfortunately I have no description of modification kit and/or list of parts involved, but only know that two diodes, one zener and a resistor plus some wire interconnections are required. I analyzed all the schematic and descriptions related in the service manuals of the 8558b plug-in and the display main frame 853A and I suppose that only two diodes plus one zener and a resistor are required with some wire connections. Can someone help me with a detailed description and/or parts list of the modification kit HP P/N 00853-60058 ? I'll be very gratefull for any help. Tnx max
I've a compatibility problem of my HP8558B S/N 1707A03258 (low S/N) Spectrum Analyzer plug-in with my HP853A display main frame. Only using it in analog mode, all seems to operate OK. I know that HP in the past released a modification kit for 8558B plug-in with S/N 2145 and lower, HP P/N 00853-60058 including some components plus wire connections to obtain full compatibility between the 8558B low S/N and 853A display. Unfortunately I have no description of modification kit and/or list of parts involved, but only know that two diodes, one zener and a resistor plus some wire interconnections are required. I analyzed all the schematic and descriptions related in the service manuals of the 8558b plug-in and the display main frame 853A and I suppose that only two diodes plus one zener and a resistor are required with some wire connections. Can someone help me with a detailed description and/or parts list of the modification kit HP P/N 00853-60058 ? I'll be very gratefull for any help. Tnx max
The purpose of the 00853-60058 modification kit was to allow the HP 853A to slow the sweep time of the HP 8558B to the point where the ADC in the 853A could digitize the video signal. Also, it permitted the analyzer to be triggered via GPIB.
I have looked high and low for a copy of the Service Note that described the modification kit and its installation, but have not found one yet. I can tell you that the diodes and resistor came pre-installed on a small board that was mounted to the bottom of the A16 Motherboard. Wires were added from this “daughter board” to the motherboard connectors of the A7 Frequency Control and A8 Sweep Generator boards and to the large connector on the rear panel of the 8558B which mated with the 853A. Also, there were wires that had to be added to both the A7 and A8 boards. These wires went to the AST (Auto Sweep Time) and trigger signals.
If you can get a copy of the 8558B Operating and Service Manual that documents serial prefixes prior to and after 2145A and compare the circuitry on the A7, A8, and A16, you will no doubt see the components that were added for 853A compatibility. Look particularly in the area around the sweep generator and trigger circuitry.
These are the best clues I can give you; I wish I could have been of more help -