Noisy JD regulator?

I've been happy with the charging voltage since installing the John Deere style regulator. I see 14.1 to 14.2 V with the engine running, and it's nice and steady. The battery is happier, all's good. Pretty much.

It's noisy though. I notice a good amount of noise in the headset, a constant low level buzzing hash that varies in tone with engine RPM. Poor filtering, I am guessing. It gets a little annoying, especially on longer flights. I'm not terribly surprised, it's some of China's finest. Probably no worse than Italy's finest. Still... have you guys who are using the JD style regulator noticed the same thing, and have you found a particular supplier that is significantly better? Every ad for that part that I see shows what looks like the same identical part, at prices ranging from $25 to $40 or so. I haven't tried hanging a nice fat filter capacitor on the output yet, but I may try that next.

I had thought about putting the Ducati regulator back in and keeping this one as a spare, but the voltage with the Ducati installed is lower than I'd like to see it.

You could try putting the Ducati regulator back in to see if the noise goes away and that the John Deere regulator is actually the cause the of the noise. If it is, maybe you just got a bad one. Mine is not noisy.

Mine is not either.

HOWEVER.......

I recently had my AV-50000 box repaired by Van's. Since installing the repaired unit, I now hear a slight buzzing and the ping of the strobes in my headsets. It is barely there, but there nonetheless. It wasn't there before.

Just another data point.

There was always a slight buzz or whine with the Ducati regulator, but it's much worse with the new one.

I think I'll try a filter capacitor at the regulator, along with a better ground... if that doesn't work, I'll try another regulator and see if that's any better. They're pretty cheap.

My money is on the 50000A. Pull the audio fuse and see if it disappears.

Well, crud.

I was going to take my wife up to check out the fall colors. She's not a big fan of flying and is pretty much terrified of the RV-12. About two minutes after takeoff, still climbing to get above the low level bumps, I got a high voltage alarm. The bus voltage was 15.5 to 16, and I caught a brief whiff of electrical smoke. It almost immediately went away and the voltage dropped to 14.0, then 13.9 -- about .3V less than it has been since I put the new regulator in.

Turned around, landed, parked it. I'll put the original regulator back in, and order a new JD style from a different and hopefully better source to keep around as a backup in case the Ducati regulator ever fails. To be honest, my confidence in either one is about as close to zero as you can get.

Stay with it Dale, there's a fix possible. I put my JD regulator right back in the same spot as the old one, but I re-worked the cooling shroud to cover the whole unit. It has been flawless for the past 160 hours. BTW, I bought my regulator at my local NAPA auto parts store. Don't know if it's any better than the cheap Chinese knock offs I see on FleaBay.

I pulled the regulator yesterday -- there was no question that the magic smoke had escaped. I dug out the rubber potting compound for a little post-mortem evaluation. Forgot to write down part numbers or bring the carcass home, but there are three large semiconductors and a few smaller SMT parts. Two of the large devices appear to be bipolar power transistors - 2N58xx part numbers, if I recall correctly. The third was unreadable because half the device was gone. It had obviously self destructed, which was the source of the tell-tale magic smoke smell.

All in all it doesn't look like a horrible design, but the physical implementation seems somewhat ill-advised. The manufacturer could have bonded the high current devices to the case/heat sink and potted the board -- but no. The PCB is stuck to the case, and the high current semiconductors are potted in rubber of some sort, sans heat sink. Maybe a cooling shroud and blast tube would have helped, maybe not. It's hard to tell.

For now the Ducati regulator is back in.