Pars

Went up to Madison, WI on the 28th to see Garbage (and Noel Gallagher, not so much for him). Concert was cancelled due to smoke, but my friend's daughter found a Zappa tribute band from Milwaukee playing at a local venue called Crucible. Opening band was from Madison, and was pretty good. The Zappa tribute band was quite good, though I didn't hear any recognizable Zappa songs. Note the Zappa effigy behind the guitarist (T-shirt on it said titties something). One of the guys said they are going to Germany to play in a Zappa competition. First 2 pics of the opening band, second 2 of the Zappa band. Made up (kind of) for the concert being cancelled. Also, some really good pizza up there (Ian's and Grampa's). My wife said that Grampa's might be the best she's ever had. Close for me.

How about the XLR shield going to chassis, with pin 1 being only signal ground? I know that probably goes against Rane, but in my mind, if you don't want signal ground connected to PE/chassis ground, you should be able to do it. I know there are Neutrik XLRs that do not connect pin 1 to chassis, but allow for shield to chassis.

Finally got around to casing this (also posted in the What are you building thread. Needs a bit of wiring cleanup, and the transformer needs to get bolted down, but sounds great.

FInally got around to casing my DynaFET. I ordered the case from Modushop in November of 2021. I will probably clean up the wiring, particularly the output wiring. Also need to bolt the transformer down. I wish I would have done the lettering a bit smaller, but overall satisfied with how it turned out, and it sounds great, even though it is single-ended.

If I bother looking at the CFA3 thread on HF, there is a lot of talk of using tube preamps in front of a CFA3. I agree, don't understand it.

Happy Birthday Jose!

Happy Birthday Birgir!

Digikey shows a VIshay SS14-E3/5AT or a Diodes Inc. B140-13-F as direct replacements.

Happy belated Birthday Greg!

Happy Birthday Justin!

So how long before another Russian mysteriously falls from a balcony? Or is that too subtle in this instance?

Very sorry for your and family's loss Al.

When the cheapest GA tickets start at $199, what the hell does this that is posted above mean? all tickets start at $19.99 down!

Happy Birthday Kerry! I hope you have a great one!

My DynaFet isn't in a state that I could try my protector board w/30V GRLV (casing it). Maybe I could rig something up this weekend to try to see how it behaves?

I take it that you have checked to make sure all components are the correct value and in the right place? From your voltage measurements, everything looks more or less identical until you get to the servo area. What are the voltages on the inputs to the opamp? Also, in your picture previously, 2 of your output devices appear to be missing screws into the heatsink. At this point, I would probably replace all the 15030s/31s given your probe slip just to make sure. These boards are pretty easy to rework.

Had a recommendation from a UK user on diyaudio for this probe system for probing small pins etc. Seems like it could be just the thing for SMD shit. https://www.amazon.com/PCBite-SP10-probes-test-wires/dp/B08FGG1QWD/ref=sr_1_10?keywords=pcbite&qid=1685552010&sr=8-10

So sorry for your loss Todd. Sounds like she was a neat lady to have as an aunt.

It almost sounds like something is oscillating. Do you have a bench supply you could power the protector with to see how it behaves in that situation? I've only built one protector board and haven't used it yet in an application. I was saving it for a CFA3. On my DynaFET (30V GRLV), I use one of Amb's boards since it is SE only.

What are the voltage in pins on the LM339s (3 and 12) at? 30V inputs seem a bit excessive for the 12V regs, but not sure about that. And you have all unused inputs grounded it seems? You don't need to do anything with the unused outs I don't believe.

A Chinese parts vendor that actually seems to be legit, LCSC. Recommended to me by a guy on Diyaudio. They are associated with jlcpcb and provide all of their parts. Needed some TPS7A3001DGNR, which are currently out to Aug. 2023 (they were out further than that when I ordered these) at Mouser. Ordered some from LCSC and they appear to be genuine (and function so). Shipping is expensive, and the more economical options take awhile to get, so I will only use as a last resort, but good to have.

Happy Birthday Brent. And yes, have a biscuit.

Happy Birthday Rob!

I haven't had any issues with the 25K, but I'm using JFET input on the DynaFET (only option). If you use the THAT BJT quads on an SS input stage, that would probably be a problem as those require low input impedance. CFA3 with JFETs is probably not a problem, though Kevin could clarify.

I don't know what the normal temperature is, but it shouldn't be running really hot. I have an SE DynaFET running with a single GRLV at +/-30V using a 120VA SumR transformer. I've never even checked the transformer for heat (never even thought about doing so), and it has run fine since about 2017 or whenever I got this thing working. The DynaFET is biased at 140mA, with 2 pairs of output devices per side. It is on 300mm 2U Modushop heatsinks, with both DynaFET boards on one heatsink and the GRLV on the other. The GRLV side is cooler than the DynaFET side, but I can hold my hand on either heatsink for as long as I want after running for an hour or two. They both definitely get warm, but not say Nelson Pass normal operating temp (i.e., hot, with you only being able to hold your hand on them for a few seconds).