Re: Info on my new NS40 Board

Johnny AC0BQ

Gm Robert
Glad you like the kit.
The credit for the design goes  to Dave Cripe NM0S.
Dave did a wonderful job of designing a "no wind toroids to wind concept"
Dave has designed several other 4SQRP kits, and keeps something on the burner most all of the time. Keep an eye out for new kits in the next few months, in the mean time, enjoy the line up we have on hand!,
Tnx 72
Johnny AC0BQ
"More smiles per Watt!"
Sent from my iPad

On Nov 28, 2013, at 9:18 PM, "Robert" <bob@...> wrote:


Happy Thanksgiving to all.

Well I was very impressed with the NS40 circuit and layout. It took about 30 minutes to build, worked as it should with an RF output of 6.2 Watts into a 53 Ohm resistive load at 12 VDC. The RF signal looked very clean on the oscilloscope and sounded great on the radio.

This is the curcuit I have been looking for for many years. A lot of us hams who got our novice license around 1958 built the standard 6V6GT tube transmitter which had an output of around 7 Watts. The 6V6 transmitter was a simple transmitter circuit and the NS40 is even a simpler circuit than that. Good show to the designers.

I measured the circuit inductors before I built the board and here are the results: L1 - 1.012 uH, L2 - .946 uH, L3 - .749 uH, L4 - .165 uH, and L5 - .480 uH. It will be fun to experiment with and modify this circuit. When I adjusted C4 from 462 pF to 590 pF, the output went from 6.2 Watts to 9.4 Watts with the 53 Ohm load.

I am basically a boat-anchor ham and my rig is shown on my QRZ page.

Thanks again to all involved with this NS40 design,
Bob Luetzow K9ZLU - Lytle Creek, California

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