Finding correct SMT diodes and transistors to fix my scope?

[rwgast_lowlevellogicdesin]

Im trying to fix the front end on one of the channels of my scope, from what I can tell the transistors and diodes in this pic are the problem... doing resistance and diode tests in circuit gives crazy values compared to the other three channels.



So far I have figured out one transistor is going to be a 2sk508-52 jfet, and it is definately bad, out of circuit a transistor tester reads it as 2 resistors!

The other three transistors labeled 3em with a sideways 4? are some sort of MMBTH10's but the sideways 4 is throwing me off I think they may be MMBTH10−04LT1G's but I am not sure.... The weird thing is in circuit only one leg of all three transistors was testing strange compared to the other three channels, using diode drop and resistance on a DMM, so I took them out. Oddly out of circuit diode drop/resistance tests doesn't work at all, the dmm says overload, but the transistor tester shows everyone with a VBE of 700mv and 6na IC.

The two diodes are labeled C1, I think they are NXP 43v zeners, but I'm not sure. I need to put my power supply back together because I don't have any other 50v source to test them with.

[wraper]

are some sort of MMBTH10's but the sideways 4 is throwing me off I think they may be MMBTH10−04LT1G's but I am not sure....

MMBTH10LT1G from Onsemi https://www.lcsc.com/product-detail/Bipolar-Transistors-BJT_onsemi-MMBTH10LT1G_C16204.html

but the sideways 4 is throwing me off

Datasheet says date code orientation depends on manufacturing location.

transistor is going to be a 2sk508-52 jfet

2SK508G-K52 to be precise.

[rwgast_lowlevellogicdesin]

Any idea if those two c1 diodes above the jfet are NXP zeners?

[wraper]

^Could be this https://www.lcsc.com/product-detail/Zener-Diodes_Nexperia-BZX585-B2V4-115_C503445.html
I suggest desolering one from a working channel if both of these are actually dead and checking if it's actually a 2.4V Zener diode. Multimeter might be enough for the test if it can measure a relatively high voltage in diode mode.

[tautech]

@OP
I have some warranty replacement boards I can pull and test/check components if required.
Let me know the DSO models.