use 2 caps, you never know what someone will try and plug into the receiving end. I would also put a 10-20K ohm resistor after the first cap and before the second cap. If you use an electrolytic the resistors will keep the caps from becoming reversed bias. I dont know, from the limited schematic what the DC values are at each end.
You show no gate bias on the 2N5458. I don't think you can find a 2N5458 which will self-bias high enough to pass the specified 3V (rms?) input; anyway THD is non-zero and not controlled in design or use.
Biasing to around half-way is normally a good plan. For both the JFET and the BJT. Which means they can be direct-coupled, NO cap between.
I do not see what you gain by putting a BJT in the end. Build all your electronics in front, then the reception is just a power/signal split. Now no DC on the signal lead of the cable.
I stole your 82uFd cap value but unless you are feeding total crap DC supply it can be smaller. But in electrolytic, not TOO small: well-oversized e-caps have very low distortion (see D.Self and others). 10uFd feeding a assumed 100K load is 0.2Hz, 500X bigger than absolutely needed, thus flaws are 500X less. (Remember most modern guitar amps and stage mixers are choc-a-block with little e-caps.)
I do think 3nF is a lot of C for ordinary cable.
Biasing to around half-way is normally a good plan. For both the JFET and the BJT. Which means they can be direct-coupled, NO cap between.
I do not see what you gain by putting a BJT in the end. Build all your electronics in front, then the reception is just a power/signal split. Now no DC on the signal lead of the cable.
I stole your 82uFd cap value but unless you are feeding total crap DC supply it can be smaller. But in electrolytic, not TOO small: well-oversized e-caps have very low distortion (see D.Self and others). 10uFd feeding a assumed 100K load is 0.2Hz, 500X bigger than absolutely needed, thus flaws are 500X less. (Remember most modern guitar amps and stage mixers are choc-a-block with little e-caps.)
I do think 3nF is a lot of C for ordinary cable.
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Thanks guys
Impressive PRR and your photoshop skill
I've checked the cable its 3nf until I found out that I have joined the hot and cold pin from end to end , i've cut cold pin, and yeah 100pf/m. OMG ive record song many clients using that cable.
82uf bcoz that fet only consume 4.56mA x 18v =82mw "then rule of thumb somewhere" =82uf? or nah?
Impressive PRR and your photoshop skill
I've checked the cable its 3nf until I found out that I have joined the hot and cold pin from end to end , i've cut cold pin, and yeah 100pf/m. OMG ive record song many clients using that cable.
82uf bcoz that fet only consume 4.56mA x 18v =82mw "then rule of thumb somewhere" =82uf? or nah?
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