Skooby

Noob question to all. On Kerry's 1.4 Dynalo v1.4 SMD board, on the bottom side, there are a couple of masked points with silk marker "AOT" and "0". What are these, jumpers? Thanks for any pointer!

That will be another option. But bend once right? Multiple bends may snap the lead.

Bummer, you're correct. The TKD footprint's too small for the mini dynalo board. Since there will be no GB for the chassis, may be I'll do a generic eBay chassis and go off-board on the back (IEC, XLR, RCA) and front (TRS/4-xlr, vol, power, se/xlr sel.). Not pretty but will work.

Pots received, perfectly in time for the mini dynalo! Thank you, sir!

May be I should follow instructions here to get my own liquid gases:

I've tried B+ relay from this article, but haven't tried the AC relay: http://www.audioxpress.com/article/arduino-based-tube-power-amplifier-controller/9883 The included C code got temp. sensing, so you can adapt it to your need. I used Adafruit Pro Trinket, half price of the Arduino board and it uses the same IDE.

I've used Jensen transfo for XLR-2-SE. Not sure it's the best/cheapest method. May be a step-down transfo's better than 1:1

Not a fan of termination blocks, Wire fray and screw down are too iffy. I just solder 18 awg wires straight to the board.

Dang, pretty good deal. Wished you had this during v6 GB. Kemet caps costed me an arm and a leg.

Always admire you guys getting silk screen prints/engravings for volume/switch/name labels back and front faceplates. Look super professional! Wonder how to get the services done in my local area. Sending the parts out seems to defeat the idea due to weight.

Check the LT1021? Not the 5V or 7V versions?

EC Studio is parallel SE -- I have his 445. On the 445, the OPTs got tertiary windings for feedback; hence extra wires. Studio uses 2A3 instead of 45, not sure if the tertiary feedback windings are still there or not. Most of the $7K is in those Tribute ITs, may be silver windings?

I put DIP switches on the jumpers. Try one at a time to see what works best. I used 'switch 2' now. Pretty stable offset and balance voltages.

Agree, Birgir 100%. This phase splitter measured like shit on the scope. But there are situations that I need SE. Like for testing, it's a pita to haul my Yggy out , so a SE CD player would have to do. Will switch the power to the splitter off when using XLR when all tests are done.

Another Carbon powered up. The chassis a tad bit long/deep but too lazy to chop 2-3 inches off to size. A phase splitter sits on top of the trafo for SE input (a power switch off when use balanced). Going cheap with Alps R27; will upgrade later. Thanks, Dr. Gilmore and everyone else for designing the Carbon. Thanks to sorenb for organizing the group buy!

Thanks!

Hi all, I'm in the process of building the Carbon (I believe the amp boards are v6) and in need of a pointer. "Servo 1" and servo 2" jumpers should be connected? Thanks.

Expertly built! Where's the volume pot?

I'm one of the guilty ones who didn't use isolated diodes; used a non-blessed BOM which specified non-isolated diodes. Blew a lot of fuses before realizing the problem. Seeing the outlet wires go directly to on/off switch, no fuse on the 120V main line? Should put one on in case of shorting (like non-isolated diodes). Also, two-prong outlet plug? Where's the ground/third prong or how do you ground the whole amp? Is there a chassis ground?

Ok, thanks...I actually can change the trafo windings to get any VAC value. If 25VAC works, no need to hassle then; hope not too much heat to dissipate.

If use GR for Carbon with 15VDC out, what's the best/optimal AC in (minimize heat/voltage drop)? I currently have 25VAC source but that will be too much heat dissipation to drop to 15VDC?

I too have used MPSW/As instead of SC/SA (my board is rev 1.0). My LED between the MPSW/A's didn't light up at first but need to adjust the 2K bias pot to get 0V between +/- outputs. May be want to adjust the 1K offset pot too. Things survived the first 30 sec, sounds promising. 63mm height heatsink?

Thanks! A/C relay or soft start as Birgir suggested would work too. But I'll stick with the 4A fuse, way cheaper solution than other options.

I just built a KGSSHV with Birgir's rev 1.0 boards. Everything runs fine, just that I have to use a 4A slow-blow fuse on the main AC. Is this a tag bit too high, any issue to be concerned with? I've tried 3.15A and 3.5A slo-blo but none worked. I used two 4700uF caps on the +/-15V rails instead of 3300uF caps (but can't imagine these created the problem). Thanks for any pointer.

Payment sent for two boards. Thanks.