Re: Class-E Amplifier Woes
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Hi Jim,
R8/R9 seemed to reduce the ringing, but I never proved this definitively.
The symmetry adjustments were included as a "just in case" feature, but I never did any further work to determine if it was actually needed, or not.
The amp's purpose really is just to provide RF for an AM signal.? So, apart from from turning on and off at the start and end of a transmission, the amp isn't being keyed as one might do for CW operation.? Never the less, there is ramping provided via C1, R1, and R2.
- Jeff, k6jca
On Sunday, June 18, 2023 at 08:42:06 PM PDT, jim conrad <conr2286@...> wrote:
On Sun, Jun 18, 2023 at 03:25 PM, Jeff Anderson wrote:
Building an 80-Meter Class E/F RF Amplifier...
Jeff, Your 80m amp inspires several questions...
- Is the purpose of R8/R9 to protect U8/U9 from excessive peak current, or to mitigate ringing, or...?
- Did you find the symmetry adjustment (R3/R6) necessary or was it more just-in-case?
- Did you ramp up/down the PA ON signal to minimize key-clicks? ?I've been thinking of doing something similar to minimize clicks when the PA turns on/off.?
-- JimC (KQ7B)
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