Does anyone know what the deal is with the options on the HP8559A spectrum analyzer?
I got a unit that has a busted ref level adjust knob, so I just took the broken plastic off and it works easily enough, if I push it in I can adjust the attenuation, and if I pull it out I can adjust the reference level, I put a smaller knob on the fine adjust but it seems to work fine.
However, I am confused by something. The manual says it is capable from -112dBm to 60dBm. Like, it says for the basic test "set to 0dBm" or set to 50dBm (if you have the 002 option, which I do not have).
The cracked plastic knob I took off has a little indicator wheel for the setting, and it spans from -100 to 70dBm.
Since the fine adjust goes from 0 to -12, so I assume the -100dBm is used, since -100+-12 = -112.
However, my unit only clicks 9 times. I opened it up and had a look at the switch assembly (without actually disassembling the switches), the traverse of the switch is blocked by a little metal rod embedded into a hole, clearly put there on purpose. This means that my unit is either -100 to -10 dBm or -90 to 0 dBm.
Only the -90 to 0 dBm makes sense, as the manual specifies that for the "002" option 50dBm should be used, while for other units 0dBm should be used.
Is this SA limited from -90 to 0, and the option 002 gives it -100 to +50? I think I can move the position of the pin to enable the knobs to traverse where ever.. but does anyone know any details on what the 002 option actually changes ? Someone speculated that they might include a beefier attenuator to support +50dB.
The knob I had is completely fubar, so I have no idea what the reference levels actually are. I read that I should not take the switches apart unless I really wanna punish myself so...
oh fuck, its a god damn analog computer knob. !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
https://www.youtube.com/watch?v=56nvlgyg9-M&feature=youtu.beI got that hunch like, 2 minutes before watching this video