Simple, Cheap, Broadband, Linear, Power Amplifier Circuit Designs...?

[tim123]

Hi Gyula,
  thanks for your reply, and the links, I'll check them out in a bit...

I did anticipate the range might be a problem, and I thought it might need a different set of mosfets for each application...

I suppose what I'm asking is: There are thousands of amp design out there - is there a particular circuit configuration / architecture which anyone would recommend from experience?

- Few components, easy to build
- Inverting output...
- Driven by a signal generator
- Run from DC supply

Commercial RF amps are expensive, and seem to need a large input signal too (i.e. from a pre-amp...?)...

Regards, Tim

[tim123]

I built this today - it's a single MOSFET amp - from this page, for running my Vialle generator replication...:
http://jnaudin.free.fr/rvproject/html/ugentest27.htm

It's not an inverting amp... But it's pretty

So, guys, suggestions, links, recommendations, experiences - for a simple inverting one?

[mscoffman]

Tim,


Usually in amplifier theory one simply swaps the load
from the source to the drain or emitter to collector.
The load is a resistor so it has two ends and attachment
to either ground or Vcc is possible. In the real world
the load maybe has one "end" and the other must be grounded.
Once the load has been swapped the designer may
have to "clean up"  the device gate or base drive and bias
so that it "steps over" the load.


In an AC amplifier a capacitor or transformer can
be used to couple of one stage to another
or the load. If one must have DC coupling then
there is usually a PNP or PMOS complement
device that can be used to help simplify the (non) inverting amplifier.
The complimentory device has similar specs but often
times the positive versions are slightly less efficient
then the negative version which are then used more
often.


:S:MarkSCoffman

[tim123]

I'm sorry Mark, but I don't understand a word of what you just wrote... Load swapping? 'Stepping over'? Coupling Stages? Say what?

I was hoping for simple circuits people have built and found to be good, or links to similar... Something practical to build... The theory is endless - it seems - and I just looking for something practical to start off with... I need to build things to understand the theory...

[Qwert]

http://www.tuks.nl/pdf/Reference_Material/Magnetic_Amplifiers/Platt%20-%20Magnetic%20Amplifiers%20Theory%20and%20Application%20-%201958.pdf

http://teslapress.com/magamp.pdf
This link is to a short document "Magnetic Amplifiers". On pages 4 and 5 (6 and 7 / 24 of the pdf) you find this (the first page):
"With the addition of two rectifiers (5), the device generates and controls a d.c. load from an a.c. supply."...
and on another page:
"Figures 6 and 7 show further developments with the addition of feedback. Gains of up to several million per stage have been obtained with these circuits."