I've got a 8595E which works perfectly fine in the high band but it's about 24-26dB down (almost flat) in the low band (9K-2.9G)
Long story short, by doing various measurement, I have confirmed that the PIN diode switch inside the SYTF when
switches to the low band is dead (exactly 24-26dB loss over the band) so it does not pass the signal through to the mixer
everything after the SYTF works fine when I directly inject low band signal. The YIG filter itself is of course fine, too.
It seems to me that the PIN diode in the shunt arm of the switch is shorted perhaps due to excessive input power. It also overloads the switch voltage
that comes from A7 board, instead of -9.8V it becomes -3.6V when that switch is supposed to close. But for eh other pole of the switch (high band) it is -9.8V as it should
Anyways, since I have never opened a SYTF or any YIG tuned stuff before
I have a couple of questions I was hoping someone on this forum can help me with:
1-what are my chances of repairing the switch and not messing up the YTF?
2-Are the switch and the YTF in two separate compartments? If I attempt to open it up
is there anything that might fall off and mess the whole thing up?
3-is the switch made of wire bonded microcircuit elements? I don't have access to any wire bonding stuff. Only my soldering iron!
thanks
