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## Re: [Amps] Need for bias switch (CW/SSB)

 To: , "Joe Subich, W4TV" Re: [Amps] Need for bias switch (CW/SSB) "Carl" Sun, 17 Jan 2016 13:12:59 -0500 mailto:amps@contesting.com>
 Which is why saying Deep Class B signifies a variation and has been used for ages. ```Real old manuals used B/C Not accurate for a purist but fine for real world use. Carl KM1H ```----- Original Message ----- From: "Joe Subich, W4TV" ```To: Sent: Sunday, January 17, 2016 9:09 AM Subject: Re: [Amps] Need for bias switch (CW/SSB) `````` > Instead it is in fairly Deep Class B in CW with a much lower > idle current which also works well in AM. Class B is defined as a conduction angle of 180 degrees exactly - therefor one can not be "fairly deep Class B". It might be deep into Class AB2 - i.e., well beyond the point at which the tube starts to draw grid current - but class B is a specific operating point not a range like AB1, AB2 or C. Class A = conduction angle 360 degrees Class AB1 = conduction angle between 180 and 360, no grid current Class AB2 = conduction angle between 180 and 360, with grid current Class B = conduction angle 180 degrees Class C = conduction angle less than 180 degrees 73, ... Joe, W4TV On 1/13/2016 12:41 PM, Carl wrote: ``````The FCC did it! Originally the rule was 1000W DC input for any mode. Then it changed to 2000W PEP for SSB only so the plate transformer was tapped and a switch added, Some of those older amps have a pretty wimpy transformer and not suited for heavy duty CW use in the SSB position. The Ameritrons with that switch change the bias but it never goes into Class C. Instead it is in fairly Deep Class B in CW with a much lower idle current which also works well in AM. The HV doesnt change. Carl KM1H ``````_______________________________________________ Amps mailing list Amps@contesting.com http://lists.contesting.com/mailman/listinfo/amps ----- No virus found in this message. Checked by AVG - www.avg.com Version: 2015.0.6176 / Virus Database: 4489/11423 - Release Date: 01/17/16 `````` _______________________________________________ Amps mailing list Amps@contesting.com http://lists.contesting.com/mailman/listinfo/amps ```
 Current Thread Re: [Amps] Need for bias switch (CW/SSB), (continued) Re: [Amps] Need for bias switch (CW/SSB), n8de Re: [Amps] Need for bias switch (CW/SSB), Jim Garland Re: [Amps] Need for bias switch (CW/SSB), Carl Re: [Amps] Need for bias switch (CW/SSB), Steve Flood Re: [Amps] Need for bias switch (CW/SSB), Vic Rosenthal Re: [Amps] Need for bias switch (CW/SSB), Carl Re: [Amps] Need for bias switch (CW/SSB), Joe Subich, W4TV Re: [Amps] Need for bias switch (CW/SSB), Carl <= [Amps] Need for bias switch (CW/SSB), Jim Thomson Re: [Amps] Need for bias switch (CW/SSB), Gerald Williamson via Amps [Amps] Need for bias switch (CW/SSB), Jim Thomson