Humax 5000C HDMI repair.

This repair was a bit longer ago. I’m just posting this because of the lack of current projects. It might be worth sharing for anyone having the same problem. This DVB-C tuner had some picture output problems on the HDMI cable, especially when the connector was touched or wiggled a bit. (no or interrupting signal on the TV set)

I suspected the HDMI receptacle to be a surface mount variant, and maybe problems with lead free solder. Such solder was a bit problematic when it first entered the market (and sometimes still gives issues).

So I opened the case, and the connector seemed still an old through-hole style. (On the pciture right hand, just below the network jacks.)

Humax 5000C with cover removed

Solder time!


Mainboard under inspection

This was in my lunchbreak at work, so I can use the microscope to inspect the solder joints more close by. Unfortunately don’t own such equipment myself (yet).

And a random fact, the microscope is probably a dutch invention. An exact inventor is unknown but guys like Zacharias Janssen might have contributed to its design.

Close to the connector must be the HDMI cable driver/interface IC. So for certainty I touched up it’s solder joints on top side of the PCB.

Also the through hole connector solder joints I touched up, just to be sure. At first sight they didn’t look broken or malformed. But sometimes it’s just hard to observe and re-soldering does the magic. Such as in this occasion!

Cable driver IC, placed close to the HDMI connector.

Through hole HDMI connector solder joints

At last the cable was suspect as well, since it was moved and messed with too much. Those cheap HDMI cables are basically not happy with any form of bending. Replacing it, fully resolved the picture problems. Instructed the owner to never bend such cables again.

Comments

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