Takeda Riken 4132 Spectrum Analyzer

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Hello All,

Iv'e been stalking and reading many of the good topics here and I finally found a reason to post!  I recently acquired a TR4132 Spectrum analyzer with the optional memory unit for my hobby lab.  The analyzer is in very good cosmetic shape and works quite well, once warmed up.  The attenuator is not damaged and the calibrate signal displays at the correct level in all settings, so I was relieved to find that!  What really helped me make my decision to get this unit is that Advantest has the entire operator/calibration/repair/schematic manual online. (for both the analyzer and memory unit) 

Anyway, the one issue I have is the momentary pushbuttons on the memory unit are shot.  They have a rubber contactor in them that has dried and become brittle.  So all of the buttons need replaced, which could be interesting if I want to fit something that won't look horrible in the front panel.  I haven't done much searching for replacements yet, but I was wondering if anybody may have come across something similar or have an idea where to search?  (Pics of button at end, and I'll get some measurements if anyone is interested)

Thanks!,  check out the following pictures for some eye candy inside the machine.

Here is a picture of the analyzer showing the cal signal at 100Mhz/division




Another view of the cal signal, at 100Mhz  (notice the center frequency isn't at 100Mhz, it took awhile to warm up but once up to temp, it quit drifting and settled at 100Mhz)





Topside



Bottom side



Memory board, look at all the 74LS logic!!



Finally the buttons that are the issue:



Button disassembled, can see the rubber contact that has dried and fell apart:

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I wasn't able to find any buttons that would neatly fit in the current panel, but I was able to fit a cheap tactile pushbutton under the housing of the current buttons.  They work O.K. but would be better with something that fit better.  But I don't see myself using the memory function much anyway, but its working again! 


Not the prettiest fix, top one that has the glue around it has a push-button under the shell.


Here is the memory in action, has a saved "screen-shot" overlayed with the current signal.