3 ms·
I had to do design and build almost exactly this for a lab in college (I did computer engineering and the first two semesters of analog design were required).
by krupan 12y ago
I had to do design and build almost exactly this for a lab in college (I did computer engineering and the first two semesters of analog design were required). It was impossible to make it work with discrete components like this due to things like uneven heating of the components. Now, in that class we were using a bread board and not a pcb and none of us thought to trim the leads on the components to keep it as neat looking as this. I'm curious how much of a difference that would make.
- analog31 12y agoThe electronics lab course that we took (in the physics department) placed some emphasis on designing circuits that were forgiving of the issues such as you cite. This led to circuits that were not as sophisticated as e.g., a modern op amp chip, but forced us to think pretty hard about how the circuit should behave. Also, maybe the breadboard was a rite of passage. ;-)
- quarterwave 12y agoThe 741 has quite a few current mirrors for bias/gain, so the bias points would be much more sensitive to transistor parameter mismatch than to wiring neatness. Also, discrete PNP transistors tend to be different from the lateral PNP's in a bipolar transistor IC process. I suppose the value in ordering such a kit is that the devices shipped are pre-matched etc, so the hobbyist may reasonably expect a first-pass success. The 741 is dominant-pole compensated, so even if there were wiring-related phase shifts at high frequencies there will be no loop gain in that region to cause instability.