Last evening, I finally got my version of the T41 on the air for an extended period of time on 75M. Talked all over the US and even down to British Honduras with my home brew amp running about 800W.?

?

I call it the "Franken" T41 because the RF portion is not a T41. This is my FPGA implementation with a DSPic CK doing the actual demodulation/modulation.? Sensitivity is such that I can hear a -127dB signal; low, but it is there. On all bands the antennas generate way more noise than the rig. The FPGA splits the RF signal two ways: One set to a DAC for the panadapter and one set to the DSPic via I2S. Other than the panadapter signals, all analog "audio" is at high-level. No calibration is needed; the beauty of getting to digital as soon as possible.

?

The UI is run by the Teensy using much of Al and Jack's code for noise reduction and equalization displaying on a 7" capacitance touch screen using an 8bit bus. The panadapter only displays +/- 48K as I like that display format the best. The display is not the ones used in the T41 as the capacitance touch "areas" of those displays are much larger than the one I am using and I need that resolution. No buttons on the front panel. Touch panel handles all "buttons" including band and mode changes.

?

CW keying is crisp and the rise/fall times are handled totally via software in the DSPic. Built-in Iambic keyer.

I'll get some internal pics up later today.

?

I should receive a PCB today that has the Teensy in place of the DSPic...? Next project and we'll see how that goes.

?

I am using Bill's BPF, LPF and control board. The control board is modified slightly to provide for a receive antenna so I can attach my Beverage. The BPF is only on the RX path as my transmitter is squeaky clean before the 100W PA. The PA board is one I got from Glenn, VK2PE many moons ago for another project.

?

I want to thank Al and Jack for putting this out in the public domain and for Bill and Oliver doing the boards.? I get great compliments on the audio and the cleanliness of my signal.

?

Russ NQ0U

Last evening, I finally got my version of the T41 on the air for an extended period of time on 75M. Talked all over the US and even down to British Honduras with my home brew amp running about 800W.?

?

I call it the "Franken" T41 because the RF portion is not a T41. This is my FPGA implementation with a DSPic CK doing the actual demodulation/modulation.? Sensitivity is such that I can hear a -127dB signal; low, but it is there. On all bands the antennas generate way more noise than the rig. The FPGA splits the RF signal two ways: One set to a DAC for the panadapter and one set to the DSPic via I2S. Other than the panadapter signals, all analog "audio" is at high-level. No calibration is needed; the beauty of getting to digital as soon as possible.

?

The UI is run by the Teensy using much of Al and Jack's code for noise reduction and equalization displaying on a 7" capacitance touch screen using an 8bit bus. The panadapter only displays +/- 48K as I like that display format the best. The display is not the ones used in the T41 as the capacitance touch "areas" of those displays are much larger than the one I am using and I need that resolution. No buttons on the front panel. Touch panel handles all "buttons" including band and mode changes.

?

CW keying is crisp and the rise/fall times are handled totally via software in the DSPic. Built-in Iambic keyer.

I'll get some internal pics up later today.

?

I should receive a PCB today that has the Teensy in place of the DSPic...? Next project and we'll see how that goes.

?

I am using Bill's BPF, LPF and control board. The control board is modified slightly to provide for a receive antenna so I can attach my Beverage. The BPF is only on the RX path as my transmitter is squeaky clean before the 100W PA. The PA board is one I got from Glenn, VK2PE many moons ago for another project.

?

I want to thank Al and Jack for putting this out in the public domain and for Bill and Oliver doing the boards.? I get great compliments on the audio and the cleanliness of my signal.

?

Russ NQ0U