I got a JFET Phono/RIAA Preamplifier kit from boozhoundlabs as a gift a couple of weeks ago. This was my first diy audio project and it was incredibly fun to learn and build! Planing to do many more.
So now the bad news. I plugged it in and all i hear is feedback and hum.
I'm just curious if people have any good trouble shooting advice? Like I said, this is my first time building. Attached are a few images of my build. It's getting the right power from my supply. The left inputs are coming from my turntable and right are going to my amp. While it looks like the color on inputs for positive and ground are reversed, that's not the case.
Thanks from BedStuy Brooklyn! And very sorry for such a beginner question.
So now the bad news. I plugged it in and all i hear is feedback and hum.
I'm just curious if people have any good trouble shooting advice? Like I said, this is my first time building. Attached are a few images of my build. It's getting the right power from my supply. The left inputs are coming from my turntable and right are going to my amp. While it looks like the color on inputs for positive and ground are reversed, that's not the case.
Thanks from BedStuy Brooklyn! And very sorry for such a beginner question.
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Thanks for replying freebee.
Correct, I'm getting no sound at all.
Checking with my multimeter, I'm getting the correct voltage across the circuit (~23V). It's 16 AA batteries in series so i think that works out correctly.
If you have any other thoughts let me know and thanks again.
Correct, I'm getting no sound at all.
Checking with my multimeter, I'm getting the correct voltage across the circuit (~23V). It's 16 AA batteries in series so i think that works out correctly.
If you have any other thoughts let me know and thanks again.
Polarity matters. With the + lead of your DMM on the + power input terminal and the - lead on the gnd or - terminal, do you get +23Vdc?
Also, the lack of consistency on your input wiring will bite you in the azz someday (haphazard use of red and black wires; sometimes on the center RCA pin, sometimes on the ground lug).
Doesnt the seperate ground wire from the turntable need to be connected to the middle ground point on the PCB ?
Thanks for both relays. Really appreciated.
Par, that's correct. See attached image for how i used my Fluke. I get 23Vdc across the circuit. Also a great point about the wire colors. I plan to fix on this build and moving forward never again!
TheMr, thanks for that. I was planning to connect that ground once my enclosure arrives. I was imagining that would not affect the circuit to such a degree that no sound was being emitted, only hum, but I could very well be wrong.
I'm actually curious if my problem has to do with inputs and outputs for the RCA. Not sure.
Par, that's correct. See attached image for how i used my Fluke. I get 23Vdc across the circuit. Also a great point about the wire colors. I plan to fix on this build and moving forward never again!
TheMr, thanks for that. I was planning to connect that ground once my enclosure arrives. I was imagining that would not affect the circuit to such a degree that no sound was being emitted, only hum, but I could very well be wrong.
I'm actually curious if my problem has to do with inputs and outputs for the RCA. Not sure.
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Just wondering, why have you connected the cartridge to the left terminals which are in and out for one channel?
This issue is resolved.
It was in fact an issue with my connection of the channels and not with the circuit itself. Let me add an annotated image in case other beginners like myself are confused.
Thanks to all for your help with my new hobby.
It was in fact an issue with my connection of the channels and not with the circuit itself. Let me add an annotated image in case other beginners like myself are confused.
Thanks to all for your help with my new hobby.
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