Hi,
I figured out that my 8340A has only 62 cal constants and not 100. Does anybody know what these 62 Cal constants look alike. In my manuals there are only the 100 value versions described. It seems, that they are not directly compatible to the first 62 of the 100 version. Reason: I changed the synthesizer from Option 5/6/7 to front panel output with attenuator. Now I would like to calibrate the attenuator. I also found some app-note of how to change two resistors for the right frequency slope compensation for the leveling circuit (if this is necessary). This synthesizer was taken from my old 8510C system, and I would like to use it as stand alone unit, as it is still in good condition. Further I realized that there are more hardware versions around. In my version there are two Microcomputer PCBs with a socketed 68k processor. I tried to change the PCB with the one PCB solution with May,88 Firmware, but it won't work, as leveling seems to be disfunctional. I guess there are also two versions of leveling circuits. maybe this can be changed by a cal constant? Is it possible to use The 8341B Microcomputer (since it seems to be the same as the 8340B version) within an old 8340A? Ah, and by the way, of course the cal-sheet was missing....
So: Does anybody know the meaning of the 62 cal constants?
Thanks,
Gerhard.
Hello Gerhard,
I have found that most 834x sources will pass specification after replacing the attenuator with only alc adjustments. The variation in attenuators is well below the power level accuracy specs. I attached 2 pdf's. One showing the cal constants, and the other showing how to upgrade from the two board to the one board cpu. One of the modifications was to solder a jumper board to the motherboard. These are no longer available, but all it does is connect pins 1 thru 11 and 56 thru 66 between connectors XA59 and XA60.