Icom IC-2KL Achilles heel

Note to all Icom IC-2KL Linear amplifier owners! If you have a chance, inspect the soldering of the circuit board of the LPF in your amp. Solder have been known to fail (cracked or dried up) in certain units of this vintage. Solder should be reflowed as soon as possible. Although this model has many safety features, unfortunately a fault (mostly open circuit in case of cracked or "oxidized" solder) in the LPF bank could promptly result in damage to either or both PA modules and possibly the 40v power supply. Also make it a habit to turn the band selector switch to all positions once in a while to allow contacts of all band change relays to self clean. Do this specially when your operation is limited to 40m alone.

There is a method to actually measure with an omhmeter the Health of your LPF bank. On the main unit board: you will need a female RCA to female RCA adaptor and jumper P5 (small grey coax connected to amp input terminal) to the P1(LPF) (the big black coax going into the LPF board). Turn amp on, short the send line and merely connect the ohmmeter prods in to the input and antenna SO-239 terminals. and watch the readings as you switch from band to band. A consistent reading for all bands of about 2 Ohms is ok! If you discover any inconsistencies as you switch from band to band, your amp needs to be serviced and all solder joints re-soldered in the LPF board. (If you do it yourself, do it in a place with good ventilation.) 73 Mon DU1FV All rights to this work and drawing reserved. Many thanks!

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