- #Icom 756 pro ii changes mode in transmit problem pdf
- #Icom 756 pro ii changes mode in transmit problem mods
- #Icom 756 pro ii changes mode in transmit problem software
For TX/+12V and RX/RF use some short and isolated wires. Both ground connections can be re-used from the SO-239 solder point. The relais (use one w/o free wheeling diode) must be mounted on the top side because there’s not enough room underneath (metal sheet cover of the tuner). Also, be very cautious with the three printed flex cables. For removing the CONTROL UNIT one has to de-solder both SO-239 connectors from the PCB.
Specifications are subject to change without notice or obligation. 1st: 64.455 MHz (for all modes) 2nd: 455 kHz (for all modes) 3rd: 36 kHz (for all modes) Sensitivity (typical): Frequency range (MHz). Remove the top lid, detach the speaker cable and remove a second internal shielding lid. ICOM 756 Pro II Specifications Discontinued Amateur HF Transceivers 756 Pro II Specifications. The best place for this patch-relais is directly on the CONTROL UNIT. For here a tiny reed-relais can add up several tens of dB decoupling. adding a short circuit for the ports in off-conditions. But there’s also a fourth method iv) that is both most effective and simple:Īs known from VHF/UHF antenna relais technique one can achieve huge decoupling values when earthing unused pins, i.e. Their cure effect, and worse their side effects too, are hard to estimate. A third method iii) is to increase the input damping of the final amp (there’s already a 3R-pi input attenuator). Two alternatives curing this ICOM implied design flaw are i) replacing the antenna relais and ii) replacing the decoupling diode by a better one. Even the antenna tuner changes the phase relation and can cause several go/no-go situations. When one of the attenuators is on (for sure not the default for 6m!) the decoupling might be ok. Depending on part tolerances the IC-756 oscillates on 6m or does not. On 6m the decoupling of both the antenna relais and the decoupling diode D131 is no more sufficient. Hereafter the RX path joins the TX small signal route via IC151 to the final amp. This is caused by a loop-back from the antenna relais (TX/RX decoupling) via the RF board, passing the persistently switched input attenuator (2 relais) and the RX/TX isolator diode D131.
Some IC-756PRO (-2) tend to oscillate on 6m. Icom IC-756 PRO II (IC 756 PRO II IC756PROII) technical specifications Icom IC-756 PRO II (IC 756 PRO II IC756PROII) technical specifications :
#Icom 756 pro ii changes mode in transmit problem mods
Icom IC-756 PRO II (IC 756 PRO II IC756PROII) TX mods 100 Khz - 60 MHz Icom IC-756 PRO II (IC 756 PRO II IC756PROII) TX expand on IC 756PROII #23 EU models Icom IC-756 PRO II (IC 756 PRO II IC756PROII) 6M oscillation problem Mods for Icom IC-756 PRO II (IC 756 PRO II IC756PROII) : Schematics for Icom IC-756 PRO II (IC 756 PRO II IC756PROII) :
#Icom 756 pro ii changes mode in transmit problem pdf
PDF Adjusments Procedures Manual with schematics for Icom IC-756 PRO II (IC 756 PRO II IC756PROII) : PDF User Manual for Icom IC-756 PRO II (IC 756 PRO II IC756PROII) : Icom IC-756 PRO II Instruction Manual
#Icom 756 pro ii changes mode in transmit problem software
Programming software for Icom IC-756 PRO II (IC 756 PRO II IC756PROII) : Programming interface schematics for Icom: Icom IC-756 PRO II (IC 756 PRO II IC756PROII)