Yeas FT-817nd Repair


The FT-817 is a low power portable rig with HF and VHF capability.


This unit was handed in for repair with the owner saying they think something happened with wrongly connected power leads.

First inspection showed straight away that the ground connections for the DC Input on the pcb, and he common mode choke had burnt out. You can see the damage in this photo (one input electrolytic has been removed already).






Luckily I managed to find an exact replacement for the choke on Mouser (Part No, 80-SH-322).  So the repair was straightforward.


With this done the set powered up ok and was working fine on receive. Nice.

However, there was no output power at all on transmit. On this version of the 817 (the earlier ones don't have it) there is an on-board fuse (2.3A) in the feed line to the PA. This, it turned out, was open circuit. Happily, with this replaced the transmit side was also working fine.

(Sourcing an exact replacement for the 2.3A smd fuse was not easy, so in the end I fitted a standard 2.5A fast acting fuse.)

The blown fuse is highlighted below (the 3-pin connector is the power feed to the PA Unit).



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