| Electronics > Repair |
| E4407B Tracking Generator Repair |
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| smgvbest:
Just an update, have had some things come up in personal life so had to step away from this for a bit. will be back with soon I hope |
| smgvbest:
Looking for help in identifying some components in PICT0007.jpg looking to identify all marked ones. the one I put a D on, the D is the only marking on the component. I think this is a dual diode package for the peak detector. I loose allot of power at the point of this component. like -25dB. this is suppling the 786.5hz RF to the Mixer (5x that but I can't measure on my 1.5Ghz SA) in IMG_2867-1.jpg |
| smgvbest:
these 2 Sot-23's marked 8F I think are 5.1v zeners but 8F can be a NPN transistor as well both read strange but reading is in-circuit. one reads 24.7K forward and reverse and other is like 30meg forward and reverse. I'll get them out of circuit to test but they are connected to V1/V2 |
| smgvbest:
Here's another area. all but the one with a ? is identified but I marked one component that looks damaged? any thoughts on that? |
| analogRF:
--- Quote from: smgvbest on October 16, 2020, 11:29:44 pm ---Looking for help in identifying some components in PICT0007.jpg looking to identify all marked ones. the one I put a D on, the D is the only marking on the component. I think this is a dual diode package for the peak detector. I loose allot of power at the point of this component. like -25dB. this is suppling the 786.5hz RF to the Mixer (5x that but I can't measure on my 1.5Ghz SA) in IMG_2867-1.jpg --- End quote --- the white elements are most likely resistors. you can check with multimeter the "D" element is most likely HMPP-3890 single schottky diode by Agilent/Avago but are you 100% sure about the marking? sometimes it is tricky to read the labels seems that all 4 pins of it have been used ??? also for a good temperature compensated peak detector it makes sense to have two diodes in one package but if the marking is only a "D" then I couldn't find anything other than HMPP-3890 which is still applicable... the element with red dot is what is used to generate 5th harmonic if i remember correctly from previous discussions, so it is probably a diode of some kind. |
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