Lightning strike at NM9P

Tim - W4TME

Yes, the ESD protection ICs designed to be sacrificial during an EMP or static discharge into the radio to protect the SCU did their job very well.

Ken - NM9P

Glad they were there! No telling how expensive the repair might have been without them. Too bad there isn't an internal test routine that displays "You fried it! Front end now unprotected!". When that happens! Ha ha!

Mike NN9DD

I had similar issue they thought caused by. Lightening and it toook out the antenna relays. About the same price to repair and very quick Mike

Steve K9ZW

Wish the good practice of sacrificial-protector ESD Diodes was more widely used.  Wrote off much gear back when back-feed on the power line from a neighbor's tree 75 ft from the service easement being blown up by lightening.

Antenna protection didn't matter in this case, as one side of the 240v service and the ground were super-energized.  Looked like an arc-welder had been fired off inside the cases when we opened the gear up.

73

Steve K9ZW

Gary Wise

As Ken wrote above, if the symptom of diode damage is an elevated noise floor, is it possible (or could it be) for the radio to tell the owner what has happened? Ken was attentive, but also considered other external possibilities for the elevated noise level.

I'd hate to think I'm listening through damaged diodes and not knowing it.

Worked Ulrich, VP6AH, on Pitcairn today. I was 5x7 with him, while he was 4x4 with me. Don't want to be an Alligator, all mouth and no ears.


73,

Gary W4EEY

Ross - K9COX

Perhaps the 7300 was performing very well (tongue-in-cheek)

Tim - W4TME

Gary - there is no way for the radio to inform you that the ESD diode is blown other than having an elevated noise floor that what is usually normal for your QTH.

You could put a signal of known strength into the radio and read the output and if they differ significantly, then I would send the radio in for service.

Gary Wise

Thanks Tim!

Gary W4EEY

Tim - W4TME

I have an Elecraft XG2 that I use for providing a (mostly) known signal level into the radio.

Doug g4ovr

Why  mostly  Tim?
Doug g4ovr.

Tim - W4TME

Because, for the price, it was not designed to be a high precision signal generator.  You will have to use it to determine the actual signal level so you have a known quality before you use it to determine the amount of attention.