I built this for those of you who have guitars with single coil pickups or indeed anything that picks up mains interference up (that annoying set of speakers in my bed room for example) anyway this little device reduces the mains hum by several orders of magnitude
it is adjustable between 45Hz and 90Hz so just put it before your amp or whatever and adjust the trim pot till the hum goes away.
it uses the same Texas Instruments TLC071 OP-AMP as I used in the last project for pretty much the same reason
This will help me out a lot! But, what does Vin mean? I'm still sort of new to this, please forgive me..
ReplyDeleteit means "voltage in" in this case it's 9 volts.
Deletedon't be ashamed - we all had to start somewhere
A bit confused...
ReplyDeleteThere's no DC path for the non-inverting input. Is this right?
Since this is a fet input opamp and has a very high input impedance, what does C3 do?
Brian Grimshaw
Deleteit is part of the filter - this is for audio (AC signals)
and I assure you it does what it should do.
Where does it goes to the board? i don´t see a Vout... (assuming out is the audio signal).
ReplyDeleteDoes tlC071 = tl071?
did you forget a 620 k resistor from in to the non-inverting input of the op amp?
ReplyDeleteno I didn't.
DeleteHi dear Paul, may is possible use this circuit as filter to remove 60Hz from single coils pickups like music man do with their buffer/filter. Thanks
ReplyDeletein theory yes, it will certainly make it quieter if nothing else - most noiseless single coils use a dummy coil to cancel out the hum
DeleteI was thinking about trying to design a proper noiseless circuit at some point for my Brian May guitar but so far I haven't gotten around to it
Paul, I will try, maybe adding a JFet preamp to calibrate the gain in dB, I've studied some about dummy coil and active pickups, and some active pickups they are a noiseless, with output buffer to give their low impedance. Thanks, if I have good response i will keep you informed.
DeleteSorry Paul for this dummy question, I'm searching TLC071 and I found in some website TL071C, isn't the same integrated circuit?
ReplyDeleteyou can use the TL071C - the other one is just a lower power version
DeleteThis comment has been removed by a blog administrator.
ReplyDeleteWill tlo72 Work?
ReplyDeleteno, it has to be a single op-amp
DeleteHello, Paul.
ReplyDeleteQuite a collection of projects you have here, I am amazed and do enjoy just looking through them picking up ideas lol :-D
Anyways, I have this speaker that once the bass pot is set higher it starts to make weird sounds as if it'd be EMI or something, I bought a ground loop isolator thingy from China (3.5mm jack from speakers to the isolator to pc output jack) and it didn't see to do much if anything at all.
My question is would this work in your opinion, I would probably have to make 2 of these circuits (as it's a stereo signal).
If so, would I need two separate 9v feeds aswell?
Hope you still come here from time to time.
Cheers from Lithuania!
Thanks for your information. Just two months ago, I'm looking for the notch filter. After a search on the web finally I have landed upon the anatech electronics. I got all my required notch filter at the best price and also I have given request to design custom notch filter and got the best product from them on time. Even you can reach out them if you need notch filter.
ReplyDelete