the gain is about 1.5db so it is not bad. RX sensitivity i add a 680pf capacitor with R12 and it is significantly improve the sensitivity. i give a try with 10R resistor but the gain was too much. For Mic audio i add a 47R resistor in parallel with R63 so no need to shout on the microphone. Choke balun at the output for RF feedback protection with FT-50-43 K1 relay replacement with ACOM D2N relay + additional -680nh inductors for IMD and spurious. Q90 was replaced with a TO92 2n3904 since the surface one hardly can sustain the heat. this mod really help for audio transmit quality. bear in mind that RF is everywhere and all wires may act as an antenna and will provide strange noise on your speaker during transmit. it will add a filtering for RF feedback via the microphone cable. Mic audio, i add a 680pf from the PTT and the ground. For C81 i add a 1nf capacitor in parallel in order to sort out the output power issue consistency.This flattens the 80 and 40M runaway power and helps the higher bands. Lower emitter resistance helps the gain and power out to finals. Replace or parallel R941,R911, R96,R942 to get 11 ohms each (I paralleled 22ohms across them). the output transformer was rebuild.ĭump the 3904s (Q911,Q912, Q92,Q93,Q96 and Q97) and use 2n22222(TO18), for those interested in 80-17M it works remarkably well and give a boost up high too. Alison’s Mod for output power enhancement and i can have up to 28w on 80/40, 20w on 20 and 15 and about 12w in 10m. the db9 IS dedicated for external amplifier switching (PTT). one push button to switch to DSP filter, in place of RF/Mic i will assign a 5 position switch.Īt the rear i add one bnc plug for the transverter. 6 push buttons for switching to band, Sdr etc etc it will be assigned with the memory manager Signal analyzer based on KD6CEC mod with an arduino nano

CW and SSB DSP filter with STM32F103 based on IK8YFW DSP filter. 100w amplifier with dedicated LPF filter driven by the Ubitx. 5″ Nextion Display (The NEXTION file from AJ6CU ) This one include inside the enclosure and full integrated = It was a long way with 8 month or development, testing and mods.

Dsp plug in nicecast agc