Orange Bass Butler [schematic]
- bajaman
- Old Solderhand
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Hi Tuck
i already corrected the schematic and pcb P2 and P3 error on the last version i uploaded !
cheers
bajaman
i already corrected the schematic and pcb P2 and P3 error on the last version i uploaded !
cheers
bajaman
be kind to all animals - especially human beings
- tuck
- Breadboard Brother
In the latest schematic C7 is still upside down.
And because I don't have the latest gerber files C4 seems to be not matching the schematic. Pin 6&7
Other than that Kicad does not complain about anything else. every connection is drawn according to your pcb and there is no unconnected pad left - bajaman
- Old Solderhand
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Ok Tuck
Thanks for those corrections
here are hopefully the final schematic and sprint layout pcb gerber files cheers
bajaman
Thanks for those corrections
here are hopefully the final schematic and sprint layout pcb gerber files cheers
bajaman
be kind to all animals - especially human beings
- Lani
- Solder Soldier
Any chance we could get a PDF of the final schematic here on the thread so I can look at it on my phone? (Sprint is on my computer and won't be able to view it until this weekend).
- tuck
- Breadboard Brother
I switched the two Gain pots but that was just to get the correct connections in PcbNew (pcb designer) of Kicad
green is the latest version, red mine to have the correct connections Also the switching was changed a bit because I noticed that I did not have the FSG in the earliest schematic
green is the latest version, red mine to have the FSG pad on the PCB This is how the switching should be. A neverending story
green is the latest version, red mine to have the correct connections Also the switching was changed a bit because I noticed that I did not have the FSG in the earliest schematic
green is the latest version, red mine to have the FSG pad on the PCB This is how the switching should be. A neverending story
- tuck
- Breadboard Brother
- bajaman
- Old Solderhand
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footswitch was connected to wrong side of C17 etc
compare your original with final correction 3
cheers
bajaman
compare your original with final correction 3
cheers
bajaman
be kind to all animals - especially human beings
- Tassieviking
- Breadboard Brother
I just noticed this one, I love it, great work.
- Tassieviking
- Breadboard Brother
Tuck, what FET's are you using for this build ?
It looks like you are using TO-92 Fet's.
I would give this one a go myself if I can find a substitute for the MMBFJ201 surface mount Fet's.
My eyesight is not the best any more and arthritis in the fingers does not help either.
Not many TO-92 Fet's left any more that can be used as far as I know.
It looks like you are using TO-92 Fet's.
I would give this one a go myself if I can find a substitute for the MMBFJ201 surface mount Fet's.
My eyesight is not the best any more and arthritis in the fingers does not help either.
Not many TO-92 Fet's left any more that can be used as far as I know.
- tuck
- Breadboard Brother
drain voltages are ~12V for clean.
The J201 for distortion only have 1 to 4V.
Will check again.
I messed up the pins on the J201 footprints but already bent some legs to correct this issue…
- tuck
- Breadboard Brother
The dirt channel kind of works, I forgot to add the expression jack. But it's very, very low in volume and there is no distortion.
The resistor and pot values are ok.
I used a cheap component tester to check all the J201. Are these reasonable values?
Drain voltage at the end. When I unplug a transistor I get around 15V on the pin header where the drain pin should be.
edit: Idss seems way off according to the datasheet.
My messed up transistors in the schematic and on the pcb. So I turned the transistors and bent each source pin outwards.
The resistor and pot values are ok.
I used a cheap component tester to check all the J201. Are these reasonable values?
Drain voltage at the end. When I unplug a transistor I get around 15V on the pin header where the drain pin should be.
edit: Idss seems way off according to the datasheet.
Code: Select all
Q1 Idss 0,1mA I 0,90mA Vg 0,62V 14,6V
Q2 Idss 2,2mA I 0,94mA Vg 0,65V 1,16V
Q3 Idss 1,1mA I 0,54mA Vg 0,38V 4,40V
Q4 Idss 1,9mA I 0,82mA Vg 0,57V 1,27V
Q5 Idss 0,86mA I 0,48mA Vg 0,33V 5,4V
Q6 Idss 2,9mA I 1,2mA Vg 0,82V 14,02V
- bmxguitarsbmx
- Cap Cooler
Is it possible that your Source resistors are a magnitude off? Like 15k instead of 1.5k?
J201's should have a very tight grouping and align with the data sheet. I sorted 500 j201's and I found no outliers, granted I bought my j201's back when they were 5 cents each.
J201's should have a very tight grouping and align with the data sheet. I sorted 500 j201's and I found no outliers, granted I bought my j201's back when they were 5 cents each.
- bajaman
- Old Solderhand
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Hi Tuck
some further suggestions: buy some genuine MMBFJ201 smd parts from Radiospares, Element 14, Mouser or Digikey and make some pcb adapters to fit them in place of the through hole parts - if you purchased your through hole J201 from China you will probably have counterfeit devices - I will NEVER by semiconductor devices from Aliexpress having been bitten far too many times - charge pumps that whine because they operate at too low frequency, 16A power transistors that have difficulty switching more than an Amp etc.
As a rule of thumb, I like to bias my jfets at approximately 2/3 of the supply voltage - in this case set the drains to around 10v dc - you can either adjust the drain resistor (preferred) or the source resistor - if you have a lot of jfets, just start with the first stage and try inserting one after the other until you find one that biases up near 10 volts at the drain terminal.
I hope these suggestions work - keep going - it looks like a nice compact build
cheers
bajaman
some further suggestions: buy some genuine MMBFJ201 smd parts from Radiospares, Element 14, Mouser or Digikey and make some pcb adapters to fit them in place of the through hole parts - if you purchased your through hole J201 from China you will probably have counterfeit devices - I will NEVER by semiconductor devices from Aliexpress having been bitten far too many times - charge pumps that whine because they operate at too low frequency, 16A power transistors that have difficulty switching more than an Amp etc.
As a rule of thumb, I like to bias my jfets at approximately 2/3 of the supply voltage - in this case set the drains to around 10v dc - you can either adjust the drain resistor (preferred) or the source resistor - if you have a lot of jfets, just start with the first stage and try inserting one after the other until you find one that biases up near 10 volts at the drain terminal.
I hope these suggestions work - keep going - it looks like a nice compact build
cheers
bajaman
be kind to all animals - especially human beings