Found this lil bad boy reading 8 Ω between bottom 2 legs, found it while looking for a problem that is preventing my LM361 from outputting, it’s getting input on both inputs, looks like a wave trying to start at gates of output FETs but noda :/
so while searching I came across this, searching came up with this “39w” @ Q250, seems to be an “rd3mw” a dot-23 39v .3ma Zener? Never seen a zener like this before. Can’t find any in stock either, left pad on board doesn’t look used but I’m not sure so wanted to check with the Kicker gurus 🙂
if I can’t find a sot-23 package can I use something else since left bottom pad doesn’t look used? Like say a glass zener of similar specs, band side being soldered on top pad? (only zener I knew of, guess they come in all forms 😅)
Thank you 🙏🏻
so while searching I came across this, searching came up with this “39w” @ Q250, seems to be an “rd3mw” a dot-23 39v .3ma Zener? Never seen a zener like this before. Can’t find any in stock either, left pad on board doesn’t look used but I’m not sure so wanted to check with the Kicker gurus 🙂
if I can’t find a sot-23 package can I use something else since left bottom pad doesn’t look used? Like say a glass zener of similar specs, band side being soldered on top pad? (only zener I knew of, guess they come in all forms 😅)
Thank you 🙏🏻
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Could it be a jfet?
What do you read (meter on diode-check) from the top terminal to either of the other two terminals. Check and then reverse the probes.
What do you read (meter on diode-check) from the top terminal to either of the other two terminals. Check and then reverse the probes.
Ahh ok, amazing bro ty!
I was told it was a BZX84C39 (39v .225w zener) “39W” but I did find replacements and no change after installing the new zener. My LM361N still receives proper V+, etc and triangle waves at pin 3&4 but there is no output on pins 9&11 (replaced LM361N as well but my source neglected to state the chip was used, I am in the process of exchanging because I don’t trust it 😅 with your IC also having that similar measurement between the bottom legs I’m thinking mine must be correct and it isn’t in fact a zener but a JFET like Perry and Bill said? But even then I don’t know of a JFET that has that low of a reading between the 2 bottom legs.
ty all for your help, very much appreciated 🙏🏻
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.685 both one way, 0 reversed.
I don’t think there’s a problem with this :/ reinstalling it 😅 now to find out why the lm361N isn’t outputting, maybe I should wait for an actual new LM361N before fishing? I did just test both 072C near the 361N and neither seem to be inputting/outputting but I do not have the preamp card installed, 361N gives same results wether preamp care installed or not, NO low side switching on output gates, which is the main goal. Power supply through rectifiers switches great.
I prolly should have stated that, my main goal, to get output low side switching 😅
I don’t think there’s a problem with this :/ reinstalling it 😅 now to find out why the lm361N isn’t outputting, maybe I should wait for an actual new LM361N before fishing? I did just test both 072C near the 361N and neither seem to be inputting/outputting but I do not have the preamp card installed, 361N gives same results wether preamp care installed or not, NO low side switching on output gates, which is the main goal. Power supply through rectifiers switches great.
I prolly should have stated that, my main goal, to get output low side switching 😅
To confirm Q250 is a J109 JFET.
Do you have a triangle wave with everything including outputs in place? Make sure U12 is oscillating and outputting a square wave at Pin 5.
Q103,C269 & R270 make up an integrator and should have a Triangle wave at Pin 4 of U14
Do you have a triangle wave with everything including outputs in place? Make sure U12 is oscillating and outputting a square wave at Pin 5.
Q103,C269 & R270 make up an integrator and should have a Triangle wave at Pin 4 of U14
