Ashhar Farhan farhanbox@gmail.com via groups.io
Tue, Feb 5, 10:33 PM (10 hours ago)
to bitx20
We have pushed the ubitx v5 into production. The intial 100 boards are here. I will update the website soon too. See the scans on https://groups.io/g/BITX20/album?id=84174.
I have uploaded the new Arduino firmware and the schematic on https://github.com/afarhan/ubitx_v5/. The new firmware breaks backward compatibility with the previous firmware as the Intermediate Frequency is now 11.059 MHz and the relay switching is different. Probably, is it is possible to patch the new code to switch between the two LPF relay switching schemes as well as the IF with some #define statements.
The new 'features' are :
- LM386 is back. All hail the cross-over distortion sickness!
- The IF is now 11.059 MHz, these crystals are easily available, with 68 pf, they give a pretty good 2.7 KHz band pass. As their frequency is away from any spur of 16 MHz and 25 MHz (the two crystal oscillators on the Raduino) hence, no spurs!
- The relay switching scheme is different. The 30 MHz LPF is now always on, the individual LPFs for lower bands are switched in or bypassed (by default). It is easily understood in the circuit diagram.
- The CW wave-shaper uses 1 uf capacitor in place of 0.1u, this reduces the key-clicks.
73, f.
