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That a challenge?

Or, here... I'll let the cat outta the bag. You have to modify the bias circuit. Using a REAL zener diode, and set the circuit up accordingly. Those little 'circuits' consisting of a silicon diode and a pair of resistors fall apart when it comes to the dynamics of a class AB (read, drawing base current at times) vs switched mode.

The 29 and other chassis run the finals class c, as does the 148 chassis in AM (to an extent, it's really b).... On SSB, you need to be able to have ACCURATE bias, which implies LOW IMPEDANCE..... Meaning, those resistors that lift the diode above DC ground automagically cause the bias to drift, causing the SSB signal to sound like a 12 watt radio on sideband being fed into a 12 pill Davemade......

--Toll_Free

[QUOTE="Toll_Free, post: 255787, member: 1736"] That a challenge? Or, here... I'll let the cat outta the bag. You have to modify the bias circuit. Using a REAL zener diode, and set the circuit up accordingly. Those little 'circuits' consisting of a silicon diode and a pair of resistors fall apart when it comes to the dynamics of a class AB (read, drawing base current at times) vs switched mode. The 29 and other chassis run the finals class c, as does the 148 chassis in AM (to an extent, it's really b).... On SSB, you need to be able to have ACCURATE bias, which implies LOW IMPEDANCE..... Meaning, those resistors that lift the diode above DC ground automagically cause the bias to drift, causing the SSB signal to sound like a 12 watt radio on sideband being fed into a 12 pill Davemade...... --Toll_Free [/QUOTE]

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