3/24/17 at 5:52am
Posts by tomb
3/23/17 at 10:45am
This may seem like cheating, but a longer relay time (~30 sec) also gives plenty of time for the NuTube to settle down before you can listen. A longer relay start cures a lot of ills ...
3/23/17 at 10:01am
JMHO, but the violence of the relay is reduced to almost zero if you increase the time for it to engage.I installed the 1K resistors on the output caps, but it had almost no effect. There is probably enough voltage remaining to leave the relay causing noise upon engaging. Again, JMHO, but upsizing the relay cap to 470uf will stop that.
3/23/17 at 9:36am
3/23/17 at 9:32am
Maybe there's a variance in microphonics from NuTube to NuTube as with glass tubes?I can confirm that mine is a bit easier to start ringing than I first reported, but I haven't experienced it going for 25 seconds. However, the ringing is sort of as you say - more of a high-pitched tone that is hard to distinguish as not being electronic in nature.
3/19/17 at 10:25am
Sorry, saw this passing through. Braid will easily get solder out of a hole, if used correctly. Use it on both sides of the pad. If that doesn't work, fold the tip into a point small enough to fit into the hole. If that doesn't work, add a bit of solder back to the hole and let the wicking action pull it out completely. Almost without fail, the solder inside of a pad hole is simply a thin film anyway. There is a place for a solder sucker, but most of the time with...
3/18/17 at 3:58pm
3/18/17 at 12:47pm
3/18/17 at 11:35am
OK. With the help of a very good friend - Dsavitsk of ECP Audio - we've solved the oscillation issue with the volume pot. There is now no noise whatsoever in my volume pot travel. Gate stoppers on the MOSFETs fixed it. A Gate stopper consists of a 1K resistor inserted between the Gate leg of the MOSFET (center pin) and the center pin connection on the PCB. It takes some solder acrobatics, but most of you will probably have an easier time of it than I did, since I had...
3/16/17 at 8:12pm
Here's mine so far: As I said, I'm waiting to clean up the bottom of the board before installing the NuTube, in case it's not moisture-proof. The smallness of the PCB surprised me. I was actually expecting something on the order of the revMH Millett Hybrid PCB, but this thing is about half the size. I used some left-over MiniMAX caps that are really too large for the space, but I got them in somehow. I also will install a couple of Vitamin Q's for the output...