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Glad to help Eagle. As I looked at it some more I think you should add one more of those .01 caps directly across the bias diode. This is to keep RF off the diode. Because of the polarity of the diode, if RF is present across it's junction, only the positive half of the cycle will be shunted to ground through the forward biased diode. The negative cycle will remain and effectively reduce the forward bias. One more cap will prevent it and keep clean DC at the transistors base.

Mack points out another good one. That bias should definitely be switched on in TX only. It's wasting power and keeping the transistors heated between keys. The 10 watt resistor won't get hot because it's only dissipating about a watt and a half.

[QUOTE="Shockwave, post: 265146, member: 10882"] Glad to help Eagle. As I looked at it some more I think you should add one more of those .01 caps directly across the bias diode. This is to keep RF off the diode. Because of the polarity of the diode, if RF is present across it's junction, only the positive half of the cycle will be shunted to ground through the forward biased diode. The negative cycle will remain and effectively reduce the forward bias. One more cap will prevent it and keep clean DC at the transistors base. Mack points out another good one. That bias should definitely be switched on in TX only. It's wasting power and keeping the transistors heated between keys. The 10 watt resistor won't get hot because it's only dissipating about a watt and a half. [/QUOTE]

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