Icom ic-736

[VA3vjc]

I have a Icom ic-736 ..very pleased with it  , still learning the split mode ..    .. my Problem is the "Auto Tuner " packed it in today . meter pegs and 10 0r so seconds it kicks out ant shows   THRU.. before to day it tuned without  any issues ..a mobile or base ??

Thanx   Richard

[njvprodux]

Richard, did you ever get the tuner in your IC-736 sorted? I have fixed a couple of these so might be able to help. regards Paul G3NJV

[njvprodux]

This is an old thread and maybe no-one will see this but in case anyone else has the tuner problem and comes here, the first thing to check on the tuner is the motors, they can come apart inside resulting in noisy or intermittent operation. I discovered a youtube video covering this on a different radio. They can be repaired. Remove the motors and carefully open them up - the plastic parts on the rotor come unstuck. Carefully clean and glue them back together - I used superglue. I used a dot of solder to hold the casing together once finished.

I also had a blown RF diode in the phase - amplitude detector section of the circuit, IIRC there are four detectors and one diode was bad. I found it by using 3 different dummy loads, one 50 ohm, one 50 ohm with a capacitor and one 50 ohm with an inductor. I used 4 different frequencies and measured the four outputs going to the CPU, 16 readings in all, then compared those readings with a similar set taken from a working tuner. This revealed the bad detector and a replacement (I used 1N7411) restored normal operation.
73 Paul G3NJV