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THE AM BULLETIN BOARD => Technical Forum => Topic started by: g4jqt on May 04, 2022, 08:53:39 AM



Title: Using cardinal CPP oscillator with IRF510
Post by: g4jqt on May 04, 2022, 08:53:39 AM
I'm attempting to modify my 1 watt (approx) QRP 160m IRF510 (http://)AM transmitter to be driven from a Cardinal CPP oscillator. Most designs require a VMOS driver between the CPP and the VMOS gate, but they seem to be for designs with output powers in the tens of watts.

My configuration shown attached seems to work, but would an NCP81074 driver be advantageous? Am I overlooking something? (The 50k pot is adjusted for a compromise between most linear mod and highest power.)

Thanks.

Ian

Edit: Mods may remove this as I have reposted in Class-E section.


Title: Re: Using cardinal CPP oscillator with IRF510
Post by: DMOD on May 04, 2022, 04:20:06 PM
You might get more visibility in this Forum:

http://amfone.net/Amforum/index.php?board=76.0


Title: Re: Using cardinal CPP oscillator with IRF510
Post by: g4jqt on May 05, 2022, 04:34:03 AM
You might get more visibility in this Forum:

http://amfone.net/Amforum/index.php?board=76.0

Thanks OM. Will do.

73,

Ian


Title: Re: Using cardinal CPP oscillator with IRF510
Post by: M0VRF on May 05, 2022, 03:05:44 PM
Yes using the NCP driver will be preferable and also looks like you've not discovered class E yet!

No need for bias on the gate.

I've got PCBs for the exact same design, CPP, NCP, IRF.

Best to use a 640 as way more power and less heat.

Not sure what you doing with 1W when you can get a 20W carrier just by adding a driver and running in the correct mode.

If you want less power just use a lower voltage.

Saves wasting all that energy!!

PM me..

JB.


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