Just read into the info on the Aion build doc about the power supply, and he mentions that the milliamp draw of the circuit is too high for a what a charge pump IC puts out. I only mention this because the LTC1144 may not put out enough current even if you are supplying it with 15 volts. This may cause a subtle but high pitched whine.
the 78L33 only puts out about 3 volts - this thing definitely needs 15 to function properly, but the main issue is that charge pump ICs don't generate enough amps. 20-30 milliamps at most, and this circuit needs way more to function properly. I've run into similar problems with the Rusty Box. I ordered an actual PCB from Aion because I want to build it up to spec with the TEC-2-0923 voltage converter they recommend.
I've built both the tagboard and the dirtbox layout of the Rusty Box - which is based on this Traynor bass preamp - and encountered the same whine - I believe it is because the circuit requires around 100 milliamps to function. Normally drive/preamp circuits are not that thirsty for current, but I have tried multiple charge pumps and could not eliminate the high pitched whine - as none of them supplied more than 30 milliamps.
I first encountered the same sound when trying to power one of my loopers that requires 350 milliamps when using a supply that was rated to only 200.
i found the kit of this pcb and read the guide(https://aionfx.com/app/files/docs/ts50_bass_preamp_documentation.pdf), there's a whole chapter explaining the current need and mentions Traco TEC 2-0923 is preferred for this circuit, like you stated earlier. that sucks when you tried two different layouts with same whine! should this layout not best be "paused' or something? nobody wants a whine in a pedal. maybe i should buy the kit like you did!
both traynor layouts it put on hold. wasn't aware of the whining and the issues with the charge pumps in these circuits. i will rework the layouts when i find the time, will scrap the charge pump and the do a daughterboard for the powermodule found the aion build docs.
Maybe I just got lucky, but I built the Rusty Box using JohnK's layout and I've had zero noise issues with it. For the power supply, I used IvIark's bipolar voltage converter (Jan 6 2014) into JohnK's Rusty voltage converter. Works a charm, no oscillation or whine even with everything dimed (plenty of feedback, though!). Perhaps that could work as a Frankenstein fix with the above layouts?
ok! small update! after using the ridiculous 78l33 instead of 78l15 ( i didnt have it) i ordered it and installed it today.the circuit works! lol! i still have some light electrical noise , i think output could be higher in output, i think connections to the pots are scrambled ( ie more output when turned 45% instead of 100% or vice versa) switches seem to work, when the boost knob is set to lo(w) it really gets low in volume. these are just my findings just know after replacing the faulty 78l33
I have some good news and some bad news about my modified layout with the Traco power converter module. First, the bad news: none of you are going to get the opportunity to verify this layout. As the good news is that, I just built it up and it sounds identical to the Aion PCB of this circuit I did earlier this week.
Just read into the info on the Aion build doc about the power supply, and he mentions that the milliamp draw of the circuit is too high for a what a charge pump IC puts out. I only mention this because the LTC1144 may not put out enough current even if you are supplying it with 15 volts. This may cause a subtle but high pitched whine.
ReplyDeletei gave it a try today.used tc1044scpa and had to use 78l33 instead of the 78l15. no output only a high piched whine.
Deletethe 78L33 only puts out about 3 volts - this thing definitely needs 15 to function properly, but the main issue is that charge pump ICs don't generate enough amps. 20-30 milliamps at most, and this circuit needs way more to function properly. I've run into similar problems with the Rusty Box. I ordered an actual PCB from Aion because I want to build it up to spec with the TEC-2-0923 voltage converter they recommend.
Deletelol 3v is nothing i will change it as soon as i can... this charge pump situation is something else.
ReplyDeleteI've built both the tagboard and the dirtbox layout of the Rusty Box - which is based on this Traynor bass preamp - and encountered the same whine - I believe it is because the circuit requires around 100 milliamps to function. Normally drive/preamp circuits are not that thirsty for current, but I have tried multiple charge pumps and could not eliminate the high pitched whine - as none of them supplied more than 30 milliamps.
DeleteI first encountered the same sound when trying to power one of my loopers that requires 350 milliamps when using a supply that was rated to only 200.
i found the kit of this pcb and read the guide(https://aionfx.com/app/files/docs/ts50_bass_preamp_documentation.pdf), there's a whole chapter explaining the current need and mentions Traco TEC 2-0923 is preferred for this circuit, like you stated earlier. that sucks when you tried two different layouts with same whine! should this layout not best be "paused' or something? nobody wants a whine in a pedal. maybe i should buy the kit like you did!
Deleteboth traynor layouts it put on hold. wasn't aware of the whining and the issues with the charge pumps in these circuits. i will rework the layouts when i find the time, will scrap the charge pump and the do a daughterboard for the powermodule found the aion build docs.
ReplyDeleteI'll let you know the stripboard dimensions for the DC voltage converter Aion recommends once I get one.
DeleteMaybe I just got lucky, but I built the Rusty Box using JohnK's layout and I've had zero noise issues with it. For the power supply, I used IvIark's bipolar voltage converter (Jan 6 2014) into JohnK's Rusty voltage converter. Works a charm, no oscillation or whine even with everything dimed (plenty of feedback, though!). Perhaps that could work as a Frankenstein fix with the above layouts?
ReplyDeletehttp://3.bp.blogspot.com/-TsErabpIPyU/UssKrgKIsxI/AAAAAAAAF3M/6xl3AguLyGY/w1200-h630-p-k-no-nu/Bipolar+Voltage+Converter.png
ReplyDeleteok! small update! after using the ridiculous 78l33 instead of 78l15 ( i didnt have it) i ordered it and installed it today.the circuit works! lol! i still have some light electrical noise , i think output could be higher in output, i think connections to the pots are scrambled ( ie more output when turned 45% instead of 100% or vice versa) switches seem to work, when the boost knob is set to lo(w) it really gets low in volume.
ReplyDeletethese are just my findings just know after replacing the faulty 78l33
An additional layout is now uploaded. Chris Stelloh ditched the charge pump and replaced it with a power module. Still unverfified though...
ReplyDeleteI have some good news and some bad news about my modified layout with the Traco power converter module. First, the bad news: none of you are going to get the opportunity to verify this layout. As the good news is that, I just built it up and it sounds identical to the Aion PCB of this circuit I did earlier this week.
DeleteYou may tag this one as verified, Anders.
This comment has been removed by the author.
ReplyDelete