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AMfone's Online AM Handbook => Transmitters => Topic started by: WO1U on March 10, 2024, 12:11:15 PM



Title: 40 meter Class D
Post by: WO1U on March 10, 2024, 12:11:15 PM
Hi,

Attached is a PDF design for a 1/2 Bridge VMCD amplifier with test data. I hope someone finds it useful.

73
Mike


Title: Re: 40 meter Class D
Post by: kb3ouk on March 12, 2024, 09:17:06 PM
What, if any, components are frequency dependent? I'm assuming C1 and L1 and L3, C5, and C6 form input and output tuned circuits. Looks like a very simple design to put on the air, especially since it would be nice to have a rig that can put out some power on 40 without the heat for summer time use.


Title: Re: 40 meter Class D
Post by: WO1U on March 24, 2024, 04:48:43 PM
Hi Shelby,

The band specific components are L1, C1, L3, C6.  L1C1 is for VSWR reduction, and L3C6 are tuned impedance matching. You should be able to scale this to lower bands using values with the same reactance on the desired band. I doubt you could get higher than 40m with these devices.

Hope this helps,

73

Mike
AMfone - Dedicated to Amplitude Modulation on the Amateur Radio Bands