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If the diode were open, there would still be voltage across it in circuit. In SSB, there is 13.8v feeding the 3.3k/1.5k divider putting 4.3v on the emitter of TR26. With R131 supplying current to the base of TR26 from the 8v source, there would still be about 5v at the base (4.3v+.7v Vbe). You need to lift a leg and test the Vf of the diode out of circuit.

If I misunderstood the schematic and one leg of VR12 is tied to the wiper and not floating, the 500Ω of the pot with the wiper not making contact could also cause this because 500Ω may be too much resistance allowing the base voltage to remain too high.

[QUOTE="brandon7861, post: 833215, member: 53724"] If the diode were open, there would still be voltage across it in circuit. In SSB, there is 13.8v feeding the 3.3k/1.5k divider putting 4.3v on the emitter of TR26. With R131 supplying current to the base of TR26 from the 8v source, there would still be about 5v at the base (4.3v+.7v Vbe). You need to lift a leg and test the Vf of the diode out of circuit. If I misunderstood the schematic and one leg of VR12 [B][I]is[/I][/B] tied to the wiper and not floating, the 500Ω of the pot with the wiper not making contact could also cause this because 500Ω may be too much resistance allowing the base voltage to remain too high. [/QUOTE]

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