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Hi Ashhar, From another post: "I am preparing a new messagijg system that works over ft8 protocol that is different from js8call. It is more like a messenger. It needs the radio to be on, 24x7 (and why not!). That will happen ay the FDIM." Any updates? 73 Wei AG6AQ

Built this wiring harness this afternoon to convert a HT Mic(Kenwood connector style 2.5mm/3.5mm) to the Zbitx, and I assume it would work with the sbitx. The microphone's speaker is amplified, I tested with a regular mic and found the sound levels were too low. The amplified audio on the mic really helps. The one thing to take note is that the speaker(EAR) needs to be connected as well because the MIC and PTT take the ground from the EAR's ground. If it's not connected you won't be able to TX. I haven't tried it on air, but listening to myself on my other radio and it sounded really good. About the same level as the internal mic.

Working on learning satellites for a few months now, building most of the gear, instead of buying stuff. TODAY for the first time, I heard my own CW by way of the satellite, monitoring an sBitx (V2) using a Ukranian transverter (neither of which seems to be terribly sensitive). JO-97, in its pass over the eastern USA around 11AM Eastern time. Main rig was older ICOM820H transmitting on 70cm through a homebrew yagi/homebrew dual axis rotator system controlled by homebrew PCB using K3NG controller, controlled by SAT32PC. With some effort I found my signal on THAT setup with a CAT correction of 5kHz (I don't know why that is so far off yet) SBITX SECOND RIG was a sBitx crudely "tee'd" in with simple PL259-Tee, so it got the same signal as the Icom820H. I was unable to provide suitable doppler correction to the sBitx, because Sat32PC doesn't seem to know how to use hamlib; however, I could have done so using Gpredict directly to the radio (which was on 192.168.1.10 in this experiment; the antenna rotator is controlled over wifi using a raspberry pi) The spectrum display on the sBitx was a HUGE help. I could easily see my own CW on the waterfall and therefore tune to my frequency! I would say as a first cut that the sBitx and the 820H were running reasonably about the same as far as receiving. These passes are ONLY 10 minutes long, but on he Sbitx I could SEE other SSB conversations going on (and they seemed to have more power than my signal.....) -- so I could QUICKLY tune to them on the Sbitx and receive them just fine! On the Icom820H (without a spectral display) you have to tune up and down the band. Signal Levels: I have the antenna system 50 feet out into the driveway. The 70cm transmitter is going through 100 feet of LMR400 to a crossed Yagi homebrew. The 2meter downlink goes first into a diplexer to protect it from 70cm pickup (https://www.dxengineering.com/parts/cma-cf-416a) and then into an inexpensive GaAs FET preamp Moonraker M-100 Professional (https://www.dxengineering.com/parts/mkr-20-001) turned all the way up, theoretically 20dB gain. At that level, both the 820H and the sBitx/transverter hear considerably more SIGNAL as evidenced by increased background noise. Without the preamp I'm pretty sure the Ukranian transverter and sBitx would hear nothing, and I'm not sure about the 820H -- haven't gotten good records on that. My experience with the used Icom 820H is that I generally do best by keeping that preamp at +20dB. WITH the preamp I have heard amazingly good SSB signals -- like full quieting FM quality! The sBitx was showing MY cw maybe 10-15 dB above the noise baseline (IF was set to 84 on the 10 meter band) but my recollection is that the SSB signals were 20-30 dB above noise -- stronger than my CW signal. (So maybe I need more oomph on transmit???) This proves that you can use an sBitx as a satellite downlink receiver with transverter and preamp. In fact, it would be a very nice one because of the spectral display!! I think it would be easiest to use a second sBitx or other transmitter to do the transmit side, with a second transverter, and possibly an amplifier to get some more power.....I was surprised that my signals looked weak compared to what I heard from SSB stations on the satellite. Photos below Gordon KX4Z

BitXers, Been playing with and learning my new zBitx and I am having a blast. I have made a couple CW contacts almost immediately after receiving my unit. I had a couple unexpected hiccups in that I wasn't prepared for the "Mini-HDMI". The other was the USB-OTG adapter that came with it was bad. Fortunately I had another stuffed in a drawer and decided to try it. Keyboard came right up and I was able to get the unit up in Host mode. I paired up my bluetooth keyboard so I no longer have to deal with the USB port for that. I am running a portable 16inch (USB powered) monitor along with the wireless keyboard and can run the rig on either 18650 batteries or my Bioenno 1212Ah based battery box. Got the clock sync'd up and started up FT8 on 20m and made my first contact within in a minute.... Great start so far. It's not a KX2 but this little unit is a lot of fun especially with all the build in apps which I still need to play with. Attached is a couple of photos. -- "POWER, WE DON'T NEED NO STICKIN' POWER" - EVERY KX2 OWNER Always respect the airwaves, 73 de KI7PBR, Gary

To find the root cause of the spurs, I worked in 2 steps: 1. I took the front panel board out of the case and connected it with jumper wires to the main board. My objective was to eliminate possible EMI from the Pi Pico into the RF board. This did not make a difference for the spurs, as they just went down by 0.5dB which is the resolution of the TinySA. 2. In the si5351v2.c code I changed 8MA to 2MA. This results in approximately 5dBm less output power (33.5 vs 38.1dBm) but also a relative reduction of the spurs by approximately 7.5dB from -28.1dBc to -35.6dBc: Reduced output power is most probably due to the fact that the zBitx uses a diode ring mixer instead of the KISS-Mixer used in the sBitx and the oscillator power to the ring mixer is provided directly by the SI5351 CLK2 output (in reality an MS5351). Also, the IF diode ring mixer gets its oscillator signal directly from the SI5351 CLK1, whereas in the sBitx there is a buffer amplifier with two 2N3904. It could be that the much higher load on the SI5351 outputs, results in some intermodulation in the SI5351, which finally shows up as spurs. Given that these spurs are a showstopper, to transmit with the zBitx as the spurs are not at least 40dB suppressed, I am looking forward to further investigation and direction by hfsignals. On Mon, Apr 14, 2025 at 11:39 PM, Ron, N6YWU wrote: -- 73, Joerg - DB2OO

Sbitx - antenna switch - swr/power coupler - antenna Previously radio showed power and 1.0 swr on 15, 20, and 40 meters with similar readings on the off board meter. As of this morning swr on the radio and the off board meter show high SFR 2 to 3:1. Removed the radio from the antenna line and replaced it with an antenna analyzer, it shows a perfect 1:1. Another radio shows 1:1 on the radio and the off board meter. Previously, maybe a month ago I had the same problem, spent time chasing down the antenna to no avail. Then one day all was well with no intervention at or in the radio. All bands that were workable for the antenna show the same behavior today. Trouble shooting help welcomed. Tim