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Philco model 70 users clean up that power detector
morzh
Odobenus rosmarus
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#12

09-01-2020, 10:19 PM
This is why I try to not improve the original schematics, add AGC and such. I want my radios as close to original as I can get them. But I am OK with folks trying to improve things.
After all, 20, 70 and 90 do sound a bit raspy.

I even think, one could take a 24A dud, extract the envelope, cut the bottom, assemble a SS detector in the base, pot it and glue the envelope back.

A bit of raining on the good sound parade though: same as achieving better quality of sound by reducing the cathode feedback cap from, methinks, 0.5uF to 200pF, any such technique results in killing the PD gain. PD is, after all, a Class B amp. If it no longer amplifies, the sensitivity of the set will be noticeably reduced.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
(This post was last modified: 09-01-2020, 10:28 PM by morzh.)
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RE: Philco model 70 users clean up that power detector - by morzh - 09-01-2020, 10:19 PM



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