>>The bands from 18MHz - 21.450MHz at least will have the offending spur stripped out in the LPFs after the finals.?? I agree that amplifying these spurs is not ideal and adds to the problem of drive...? I speculate that this is why there may be a low in power output around these frequencies?? <<
No.? The filter in use for 18mhz is the one used for 14mhz and has a lower cutoff around 20-21mhz and
the firmware selects the 35mhz cutoff filter for 21mhz or higher.
They have no impact on low output.? Its simply the gain of the amp at 80m is around 61DB and by 10M its barely 50db
and the IRF510 are not the offenders.? If the amp were perfect the spur would be greater.
Allison
