The JSCARC EOC tuner saga



I’ve been working on trying to repair the Building 30 Emergency Ops Center external tuner.  This is a big deal since our club is  chartered to support the center emergency radio capability.  Thanks goodness it wasn’t needed during Harvey.

The defective tuner is an MFJ 998RT full KW remote tuner unfortunately with a known speckled reputation of reliability.

Our EOC capability is currently inop due to this broken device, likely hit by lightning.

After valiant clever attempts to fixed the “No Interface PIC” and “Wake up” circuitry and after a  replacement of a a PIC controller, the tuner is still not working.

I have to admit when I opened up the lid, the workmanship was poor.  Evidence of rework and poor solder joints were obvious.  It was not an impressive sign of good quality.

Yesterday, MFJ had kindly provided me the direct phone number of their ATU engineer, which was possibly my last hope to get this going along with their consultation.

But…. by happenstance, this Monday,  John Maca calls me and asks if I would like the look at one of the previously failed tuners also which fell victim to the EOC rooftop years ago.

Wow, this one was an SGC 235.  SGC products are one of the Cadillacs of the the tuner business with huge reputation of solid design and fabrication.  This was worthy of a fix.

John mentioned that he saw some carbon near some caps.

Here’s what I found tonite:





Stay tuned of progress.

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