I think I may have fried D1 in the circuit below, if that seems plausible? (During my initial testing, with up to 15W of input power, I had an open circuit after R4. I really don't understand how this circuit works but I figure if half of it was missing the other half could have felt some pain.)
Testing D1 still in circuit, I do measure a 0.321V drop in the forward direction however I also measure 2.209V in the reverse direction — this seems unexpected. The other diode, D2 measures 0.320V forward and OL in reverse. So I think I should replace D1.
The problem is I'm not sure what I can replace CDSH270 with. Digikey does not find results for it; Mouser says it is discontinued with 1N276 BK as a "possible replacement"— it is also a non-stock part afaict. Even if I could track some down, how likely is it to work? On what basis would I make that call? They have the same forward voltage drop, but e.g. the replacement has only 40mA maximum forward surge current instead of 0.75A (!?).
Also, I have on hand some 1N5711 Schottky diodes. They certainly seem even more different in specs, but again I'm wondering if use as an RF power detector in the <30MHz range is all that picky?
Basically I'm looking for a pair of easily attainable replacement diodes for this circuit. This is in a recently-purchased kit, and I'm worried that if there was a more affordable component they'd have used it instead :-(
