The MFJ-945E tuner repair and N connector swap


I purchased this tuner a while back because it was cheap, it has served me well for a good long while. I noticed that I was occasionally getting crackling and silence, I figured something must have come undone inside as I use this tuner outside a fair bit and it gets moved around, I had a peak inside and sure enough the output terminals PCB track had lifted off the circuit board.

Here is a picture of the tuner in question :

Here is a picture of the wire which connected the circuit board to the "Antenna" terminal on the back of the tuner, note the part of the PCB track that has lifted off :

What I decided to do is since I mostly use N connectors for my coaxial cables was to replace the UHF receptacle on the back of the tuner with an N connector, I started by removing some of the coating near where the PCB track had lifted off the circuit board and soldered on a twisted copper wire, I soldered the other side into the replaced N connector. The wire was originally just one strand but I thought it better to twist two together for better handling of higher power levels. Here is a picture of the connection to the new N connector:

The tuner is now working nicely, no more crackling or sudden drops in signal. I will eventually change the tranciever connector receptacle to N style too but currently all my patch cables have UHF connectors.

Here is a picture of the rear of the tuner with the N connector for the tuner output :

-pork9000 19/02/2014

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