Where is this "master cal" to be found? I have a uBITX V4.3 stock that is way out based in what I'm hearing. Perhaps the BITX20 is entirely different. I'm not very familiar with the Raduino so,

Thanks for your kind words, Allison ;P Agreed on both comments. Pursuit of the "All Band Antenna" is the albatross around the neck of many newer hams, and many OMs as well. The antenna with the

It appears that I have solved the problem! While analyzing the circuit further, I realized that the large capacitor C52, which is charged during receive, would feed back through R52 and R18 keeping

Raymond, Nobody was ever able to explain to me what that Master Calibration number represents, so I never knew what number to add or subtract to nudge it one way way or the other, so I decided to

Would they not just need band pass filters for whatever the desired band is? I kind of see where you might be able to suppress spurious emissions in a tuner, but why? My limited understanding is that

Hi Joel, I am having a similar issue and just can’t seem to hit on the sweet spot. I am right now only .050 off frequency but it is enough to make it annoying. My master Calibration is 143000

Arv seems he was rather confused. I possibly should have spotted same before I wrote my detailed explanation. cheers

Generally 10-20MS is fast for a relay. Keep in mind for 80M, 5 relays have to switch so you always plan for the slowest which in the case of this is a cascade of two. To go to transmit The Raduino

A possible firmware fix for the LPF relay delay would be to add a pipeline delay to all CW code elements, not just the starting edge of the transmission. The sidetone could happen immediately, so the

The inductance meter reads 97uH to antenna, and 38uH to ground. The first one I bought that looks like this model and is a 1:1 balun has shielded cable to the toroid and shrink wrapped magnet wire

IT is likely a verbatim copy of THe EARC design copy enclosed.

I'd be fine with constantly powering the LPF relays on my rig. And may be the best solution. Though does raise power requirements a bit during receive, an issue for those running from a battery.

There are a great many articles available on-line for Gama Match Antenna. Do a Google search for "gamma match antenna" to see what is available. Arv K7HKL _._

Thanks a lot, that will help !! Kind regards

Jerry, There is a simple mod for that. Rather than a delay in the code that might mess with the first CW character just apply DC to the relays. It requires an etch cut between kt3 and K3 and a wire

Okay you got a trasformer. If you have an LC meter, which inductance values do you read across the SO239 and across the two terminals for the antenna and the ground?

it happened to me, i just turned the unit off and back on, and it was fine. kevin

The LPF relays only get powered when TX_RX is asserted, which puts 12 on the TX rail. So there should be a delay in there between when TX_RX is asserted and the first time that CW_KEY is asserted.

The earlier versions changed the USB to LSB when tapped.

I just received my 1:9 unun today and opened it up and saw white silicone trying to hide insulated CAT5e cable wires, colored stripes and all wrapped around the toroid, can't even see how it was