> As I began thinking about that, it occurs to me that any
> meaningful test would not be that easy. As soon as I
> remove the tuned input, the load for the exciter changes
> substantially, which means impedances and drive changes.
> Those things alone could change the imd sufficiently in
> the exciter to show a few db difference in the imd of the
> amplifier.
>
> That would imply that a lot more testing would be required
> to understand what is being tested. Perhaps one of those
> class A transceivers would be useful as a driver.
You either need to run two radios through attenuators into a
combiner and through a 50 ohm input class A amplifier into
the amp (I use a class A 8877/3CX1500A7), or find a radio
that by itself has -50 to -60dB IM products at full
amplifier drive.
73 Tom
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
|