On Tuesday a new tx (gw3uep design) was built and worked very well.
An IRFP140, sm capacitors and 1mm wire was used although L2 (7uH)
beacme quite warm. The 1 uF caps (type unknown... yellow and stamped
BEC C11C) did their bypassing without complaint.
Roelof had an O copy on yesterday morning (the 7th) during the
first on the air test.
G4JNT Andy's explanation of how the reactances are absorbed by the
L network which brings the drain impedance to 50 ohms is enlightening.
Is there a way to find impedance at the drain or is this just the
R value on Alan's G3NYK Class E spreadsheet?
The new TX will be on again 9 Apr. 0000-0900 utc
Hopefully this design will be merciful on FETs. If not, there's a
3-500 waiting on the shelf.
73's
Joe VO1NA
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