The IC-706MKI is too noisy (adjustment)
The IC-706MKI has a fan running permanently – when receiving at lower speeds, after keying it starts in full. As the fan wears, it becomes more and more noisy. It is advisable to buy a new one and replace it. Even after this operation, however, the noise, especially when the device is quenched, is disturbing.
That it's quite annoying, evidenced by the number of adjustments. However, most are complex. If you do not bother the IC-706 at full power in FM, RTTY or SSTV on KV, a very simple solution is offered. Insert a precipitation resistor into the fan inlet, which reduces both reception and transmission speeds. The procedure is relatively simple…
- Turn off TCVR
- Disconnect all cables
- Assemble the bottom cover of the IC-706 by loosening the base of the screws
- Two wires lead to the fan from the printed circuit board
- Break one of them and plug in a trimmer there 100 ohm
- Connect the power cord. Set a lower voltage on the source (approx. 11V), so that the fan later starts under all conditions
- Turn the slider to find the point, at which the fan stops. Try turning TCVR off and on, whether it will run.
- Determine the resistance value with an ohmeter and replace the trimmer with a fixed resistance. Don't forget to insulate everything precisely! In my case, it was 18 ohm
- Cover the TCVR
The temperature of IC-706 will rise only unnoticed, while the reception noise drops by half, when broadcasting by a quarter. I did not register any problems with overheating.