i think i biased it a little too much seems to consume 3W at idle.
I would breadboard the circuit first for any fault finding and fine tuning. You may find C1 is of little or no benefit. ensure R3/R4 are low enough not to current starve the output BJT's, but high enough to manage there heat dissipation. All transistors should be mounted to the same heat sink for temperature compensation.
I think this circuit is simple, but if it works it should work very well indeed for a low wattage amplifier. 😎
I think this circuit is simple, but if it works it should work very well indeed for a low wattage amplifier. 😎
breadboards suck, or at least the ones i have they never cotact and putting in any resistors is pain, i should buy a bunch of goldpins and make my own breadboard.
I found the same, especially with 1/4W resistors. I found cutting of excess leads and bend them back double, so there 2x lead width really helps. Just watch your fingers 😉
Some picture of a solderless protoboard was removed here, so my remark does not apply any more.
I my view breadboarding in general means a hard wired test structure (even on breadboard wood), without dedicated pcb, but solder experimental boards and copper planes are also included.
Source : https://www.electronicdesign.com/te.../jim-williams-battery-stack-monitor-prototype
https://www.edn.com/honoring-the-late-analog-great-bob-pease/
I my view breadboarding in general means a hard wired test structure (even on breadboard wood), without dedicated pcb, but solder experimental boards and copper planes are also included.
Source : https://www.electronicdesign.com/te.../jim-williams-battery-stack-monitor-prototype
https://www.edn.com/honoring-the-late-analog-great-bob-pease/
The protoboard you had as a picture (in post 1?) will get you into trouble.
This is mainly due to contact integrity.
In the past I made experimental circuits with Hirschmann board which is
of high quality, can be cleaned easily and repaired, but if you do not need
to use integrated circuits, old style breadboarding is easier.
"Refined" examples made by Joachim Gerhard can be seen in this forum.
Picture source : https://holgerbarske.com/allgemein/schattenwurf/
Your bias (post 1) is dependent on R3 and R4.
This is mainly due to contact integrity.
In the past I made experimental circuits with Hirschmann board which is
of high quality, can be cleaned easily and repaired, but if you do not need
to use integrated circuits, old style breadboarding is easier.
"Refined" examples made by Joachim Gerhard can be seen in this forum.
Picture source : https://holgerbarske.com/allgemein/schattenwurf/
Your bias (post 1) is dependent on R3 and R4.
You might consider bootstrapping R3 and R4. That should improve available drive current to the outputs, especially if you are increasing their values for reduced bias current.
i breadboarded a bunch of diamond buffers before, i just want an nice solution for an cheap amplifer that i could built for cheap
It is my favorite technique even if it is a bit difficult to maintain afterwards. It is not nice but the performances in noise and high frequency are excellent.
Thank you for the link about Bob Pease. It reminds me the time of my first job in an analog electronic design team when we were waiting for his new article in EDN.
Like I said, your design should work very well. It's cheap enough, if your PCB is < 100mmX100mm then JLC makes these much cheaper.
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The easiest is to put their top face on the ground copper surface.( up side down?). The decoupling capacitors with short leads will help to keep it in place the time to add the other components.
It is fine for prototype, one or 2 samples. Not more.