Andrew, it's completely clear !
First solder :
Much easy with pcb
Phil.
First solder :
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An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
Much easy with pcb
Phil.
Rz and Cz need to be close to the chips output pin. This is to reduce wire inductance as this RC snubber needs to bypass at high freq. otherwise it works, but at higher THD.
the return of Cz goes to the common pins of the PS +/- bypass caps. Normally bypasses include smaller caps ~0.1uF close to pins! this junction is ground return heaven.
it's a common mistake to think Rz and Rz is a zobel for the speakers purpose. its really a snubber absorbing switch HF noise and stabilizing the feedback phase shift.
when I do P-P construction I place the smaller caps 1st for shortest wires and build outward from there. The gain resistors are usually placed 2nd to last.
the return of Cz goes to the common pins of the PS +/- bypass caps. Normally bypasses include smaller caps ~0.1uF close to pins! this junction is ground return heaven.
it's a common mistake to think Rz and Rz is a zobel for the speakers purpose. its really a snubber absorbing switch HF noise and stabilizing the feedback phase shift.
when I do P-P construction I place the smaller caps 1st for shortest wires and build outward from there. The gain resistors are usually placed 2nd to last.
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Post#41, R2 has a cold solder joint. That needs flux. Got some?
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Hi,
Pict is better than your eyes to see !
@ infinia, thank's I will add 0,1 uF in // with caps (schematic post 1 corrected)
@ John, I have not mica, I hope for few watts this pad was good enough. Otherwise I order mica pad.
Phil.
Thank's, I saw that with photograph, I resold this..
Pict is better than your eyes to see !
@ infinia, thank's I will add 0,1 uF in // with caps (schematic post 1 corrected)
@ John, I have not mica, I hope for few watts this pad was good enough. Otherwise I order mica pad.
Phil.
remember his power is lower than max Pd due to +/- 15V battery powered rails. Does Mouser / DK & Farnells still carry mica semi insulators?
Hum, luckily I found mica in a drawer, I do not know what I have in my diy room :
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Not the right size, but it's ok..
So what choice, thermal pad ou mica for only 5 watts ?
If I want later try this amp with another PSU (for much power), maybe mica was better..
Phil.
The 15+15VDC is getting close to max, depending on the speaker. . . so anyway, some mica pads and good thermal paste is wise.
You might want to trim just R2 back to 25k~26k range for slightly more bass dynamic power.
An input cap would help (range 1u~2.7u), so that you don't blow up your source device.
C1, C2, should be one of these options:
220u or
270u or
220u||220u (maximized bass dynamic impact power)
And, don't waste the fuses--make 'em pull dual duty as beneficent filter elements, simply by locating them directly at the edge of the amplifier board.
How big is that garden anyway?
You might want to trim just R2 back to 25k~26k range for slightly more bass dynamic power.
An input cap would help (range 1u~2.7u), so that you don't blow up your source device.
C1, C2, should be one of these options:
220u or
270u or
220u||220u (maximized bass dynamic impact power)
And, don't waste the fuses--make 'em pull dual duty as beneficent filter elements, simply by locating them directly at the edge of the amplifier board.
How big is that garden anyway?
220 uF instead 100 uF :
Please note that Ci is 100 uF, cause I have not 47 uF, what it's change with quality midrange ?
Phil.
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Please note that Ci is 100 uF, cause I have not 47 uF, what it's change with quality midrange ?
Phil.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
Not easy at all
Last time I build without pcb..
I will check (two time), and then connect to batteries.
Andrew, I cannot twist wires, ptfe is too hard, and solid copper also, mostly for a very short distance.
Phil.
The 100uF is closer to good specs. If desired, bypass with a little green polyester dip cap in the range of 10n~27n.
The main audio effect is less blur.
Also, that input caps will be easier to select and use.
P.S.
To avoid cold solder joints, use Gel Flux for any re-work. Gel Flux is a compound of rosin in petroleum jelly. It can make a second, third, fourth attempt look as good as perfect at the first try.
Speaker return (speaker negative) is a high current line that was supposed to go to the 0v centerpoint of the 220u power decoupling caps. Those wires needs moved.
Also, insert a small value cap (1u~2u7) in series to the RCA Jack + so your music source device doesn't burn up. Those caps need added.
Also, insert a small value cap (1u~2u7) in series to the RCA Jack + so your music source device doesn't burn up. Those caps need added.
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Thank's Mark (and Daniel), speaker return was moved (centerpoint of the 220u)..
Ground Loop Breaker ? you are right, I don't know, at this time, it is useless..
First time I want to have a "separate" between 0 volt and input ground !
Maybe attached schematic was better..
Phil.
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