some more PXXX 😀 😀
got yet to solder those little upside down bastxxxx... but I've a cunning plan😎
regards,
CarcasS
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.
got yet to solder those little upside down bastxxxx... but I've a cunning plan😎
regards,
CarcasS
"buena instalacion" good instalation
Man that installation look great and the coil inductor look neat, the heat sink is just right 😀 hell yeah !
Regards
Juan
Man that installation look great and the coil inductor look neat, the heat sink is just right 😀 hell yeah !
Regards
Juan
transistors soldered already 😀😀
now... I'm out of fuse holders.... I can only buy them Monday... oh well, got to drill now...😎
now... I'm out of fuse holders.... I can only buy them Monday... oh well, got to drill now...😎
An externally hosted image should be here but it was not working when we last tested it.
it's getting late here...
no fuses (even temporary 😛) for today, but at least one heatsink fully drilled and tapped!!!
😎😎
no fuses (even temporary 😛) for today, but at least one heatsink fully drilled and tapped!!!
😎😎
An externally hosted image should be here but it was not working when we last tested it.
man you got skills wow 🙂 sorry don't worried about the fuses, is better to wait lol
Regards
Juan
Regards
Juan
SUCCESS!!!!
IT'S ALIIIVE 😀😀😀
it bias ok now, AFTER I've replaced my wimpy 250mw (or maybe it was 500mw) 10V zener for a 1.3Watter... it was giving me headaches...
now I've forgotten to replace the 68r to 82r as Carlos suggested and I'm finding that BC556 (B) hot at ~44ºC... so dunno if I'm removing the resistor or simply soldering another 10r over it (78r should be close enough?!)...
anyway ... I'm going slowly, so maybe tomorrow I'll inject it some audio 😱😱
IT'S ALIIIVE 😀😀😀
it bias ok now, AFTER I've replaced my wimpy 250mw (or maybe it was 500mw) 10V zener for a 1.3Watter... it was giving me headaches...
now I've forgotten to replace the 68r to 82r as Carlos suggested and I'm finding that BC556 (B) hot at ~44ºC... so dunno if I'm removing the resistor or simply soldering another 10r over it (78r should be close enough?!)...
anyway ... I'm going slowly, so maybe tomorrow I'll inject it some audio 😱😱
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.
Can't wait to see the results bro 🙂 and yes that particular transistor BC556 it does get hot a bit but I have been using my Dx Super A since last year and no problem, let me know how you find the music, looking good indeed sir, about Carlos I haven't seen any more post from him maybe he is sick or something like that I hope he is ok.
Regards
Juan
Regards
Juan
Carcass,
what current was passing the Zener?
What power was it dissipating?
A low power Zener is OK if you don't overload it.
You have to check what you are passing through it.
what current was passing the Zener?
What power was it dissipating?
A low power Zener is OK if you don't overload it.
You have to check what you are passing through it.
my guess is that on powering up (with a 60W bulb and 2 10r resistors) there is some sort of initial "surge" that overwhelms it... doing the math (with no input) gives me just a few picowatts of consumption...
With 1 multimeter across the 10r resistor I got the bias climbing, soon as I connect the other 10r resistor with 2nd multimeter, bias "reseted" to ~0.1v and didn't change no matter how I turned the 200r pot and no voltage arrived at the emitter resistors.
So my guess was to change the 10V zener (BZX79-B10 500mw) to a higher rating and presto the boards started to bias ok with the 2 multimeters attached, and I got that nice soft glow from the bulb confirming the current draw...
With 1 multimeter across the 10r resistor I got the bias climbing, soon as I connect the other 10r resistor with 2nd multimeter, bias "reseted" to ~0.1v and didn't change no matter how I turned the 200r pot and no voltage arrived at the emitter resistors.
So my guess was to change the 10V zener (BZX79-B10 500mw) to a higher rating and presto the boards started to bias ok with the 2 multimeters attached, and I got that nice soft glow from the bulb confirming the current draw...
Now measure the Vdrops and calculate the currents. Use that to determine the dissipations in the resistors and LEDs and Zener.
I'll do that later on for sure, eager to try the data record feature on my new multimeter, maybe it saves my "suspected" initial surge until it settles down.
Hey carcass! I like the detail of bending those parts the way they do not have sharp 90 degrees 😉 I have seen it only a few times. Excellent job
thanks lanchile, it's been a breeze to build (nice work from Juan) and taking my time it's nice to "not" use pliers for bending... I mostly use a small screwdriver, hence the curves 🙂
updates now, I really have to change the 68r, it's getting bloody hot, even though far away from the 150ºC Max rating...
I've tested it with 4 8r (32r) 10W resistors and injected 770mv 1KHz sinus several minutes, and after several volume up/volume down, bias remain stable always under 1mv across the .22r resistors (the slow matching payed off 😉 ) I'm using a cheap android tablet with a signal generator (voltages measured from the tablet's output)
dc offset with no input varies from 1 board circa 7~10mv and the other 12~14mv, very happy with it... so tomorrow time for a speaker and some music...finally!
For the rest of it I'm in need of €€€ again, missing the case and the VU meters and drivers, already sorted the filter, soft start, dc protection and some other bits 😀😀
I'm eyeballing an used 30Mhz scope, so maybe I'll torture test it some more...
regards,
CarcasS
updates now, I really have to change the 68r, it's getting bloody hot, even though far away from the 150ºC Max rating...
I've tested it with 4 8r (32r) 10W resistors and injected 770mv 1KHz sinus several minutes, and after several volume up/volume down, bias remain stable always under 1mv across the .22r resistors (the slow matching payed off 😉 ) I'm using a cheap android tablet with a signal generator (voltages measured from the tablet's output)
dc offset with no input varies from 1 board circa 7~10mv and the other 12~14mv, very happy with it... so tomorrow time for a speaker and some music...finally!
For the rest of it I'm in need of €€€ again, missing the case and the VU meters and drivers, already sorted the filter, soft start, dc protection and some other bits 😀😀
I'm eyeballing an used 30Mhz scope, so maybe I'll torture test it some more...
regards,
CarcasS
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