sorenb

@mwl168: I'm in for two sets

@Joamat: have had many wet dreams rgrd the TI59 back in the days ... I really miss the red rube like display - had some magic to it

I hope you did remove the batteries before storing? or at least they haven't leaked ... there a few articles in PPC rgrd synthetic programming on the HP15C ... not of much use, but rather entertaining if you want to fiddle a bit with the intrinsic of Saturn

@Grinding Thud ....oh yeah .....from back then ... actually my first ... bought it when it came out ... switch from Texas TI57 (miss that disply anyways) ...I don't collect ....but manged to have a few anyways: Actually its been years since I last did a program on the 15C ...did it today, matching some transistors ...a small program calculating the Hfe ....funny how things get stucked in your mind ....took less than 30s and off I went ... loving this flashing "running" when it steps through ten lines of code ...

Finished populating my KSA5 today. Tried to match transistors since I had a stash of mpsw06/56 from my dynalo builds ... it really takes a considerable amount of time if one lets the transistor stabalise before testing the next. The build it self wasn't particular complicated, but one has to take care that all transistors get into the right place and have the right orientation ... well, I guess everybody here knows that, but with so many trannies it is easy to miss one or two ... I did do that fuck-up building one dynalo ....ending up having 10V on the output ...anyways I manged to get through without any errors this time....that is almost ...turned out that I missed a 39pF and two .1uF when doing the BOM. Hook it up to a Sigma22 PSU at 2x24V ....without any smoke .... less than 50mV on the output (input grounded) ....put a load on and a signal ....everything seems fine .... this bastard gets hot when running ... I dare think of how hot it will get when ever I get around to boxing it A first listen using my HD800 sounds very promising. But so does the dynalo Thanks to Kevin/Birgir for bringing this clone to the community

@Kevin: Yup...right heatsink on the boards I have is not grounded @Kerry: Thanks in rgrds to boxing the amps I have a few observations, one is that the almost square boards forces to be mounted horisontal (unless you want something bigger than 2U) that is why I asked Kevin to do a split version of the golden ref psu HV and LV, one side is less than 2U. The teflon sockets I use for the tubes in the KGST makes it impossible to cram the amp inside a 2U ...using 10mm standoffs ....the height is 950mm ....I really admire your KGST but since I am currently short of a CNC and don't have any experience in doing PCBs that is really not possible 4me to copy

1kw Xenon strobe in a cardbox??? ....have you seen "Glasslinger" on Youtube doing a 50kV power supply?

Couldn't trim the 100pot to get 10mA from the CSS ...had to change the 250ohm -> 100ohm ... used JimL method of adjusting ....apart from using the LV rather than a battery and measured the drop across the 100ohm at B+ rather ...the method works fine .... had to lower the 1k5 -> 800ohm in order to offset adjust the amp again .... Sound impression: well for what it's worth, I find it sounding super tight and fast ... expected to get some hum/noise from using the 'open architectur chassie' having heater wires lying around ...but the amp is dead quiet ....no hum, no hiss, just dead quiet Don't know whether it will change sound signatur over time ... have limited expereince with tubes...

Forgot to mention, that this is apparently the first KGST build using the boards with cascoded CCS from MWL168 GB. /S 7 july 2015 Began building my KGST friday, starting with the PSU (using the one from KGSSHV). Powered up the PSU HV sunday. All seemed honkydory ....hit +/- 351V ....and stable using 10k loads ....had it running for an hour or so, no problems. Powered up the LV +/-15V ...then I got the crazy idea of checking the BIAS ....480V ....what?? hmmm ... found my fuck up ....had mixed up some zeners. After replacing those, I got 581V. Then the amp boards .... assembled pretty quickly ....it is a lot easier than the KGSSHV onboard in my opinion ...anyways ....finalized them this evening, and powered both up. Apart from starting out having -350V on the output and then in 30 secs or so quickly falls it seems stable. Adjusting the balance/offset it sits at 0-5V at all outputs ... Here's a few photo's

PM sent; I'll go for the two SMD boards

@joamat: - why did you change the servo? - do you do your own Stax jacks? ...looks like that from your pic??

I like that chassie a lot ...reminds me a bit about that kids toy where you have to balance a ball through a maze using some handles on the side ....nice wood work ...did you use a router/template or did you do it be hand?

@spritzer: the KGSS you sold me does actually get quite hot ... and does sound lovely

Thanks Kevin for inspiration ;-)

Very nice indeed ... do you have any carbon boards 4 sale?

@pars what are those connectors you're using for PSU and input/output? btw nice airy chassie you have there .... have one almost similar ...please don't comment on my dips Par

almost look like the amp can fit inside the pot ...

@nopants: sounds like its easier to drill those out?

Wouw ... emerging from steel, glass and rocks ...very nice. Con grats :-D @Pars: DIPs rated at 1000V and 3A ....

@n_maher: not kiddin, and also aware but totally forgot ...thx!

@nopants: I see that you have left the 'open architecture' of the Megatron :-D ....looks promising though!

Stumbled across this: I guess you would be able to regulate the BIAS from 350-580V using this?

@luvdunhill: nice little utility PCB ... ...could we get a PCB containing all the neat utilities? ....XLR in/out combined with alps ....the Stax jacks PCBs ... on/off switch ....bla bla, and so forth ...if someone would do the gerbers I'd do a GB on that ;o)

ok ok ... my bad .... if you build your zener string to get 580V from something that gives you 230 somewhere ....why not tap the NB from there using a few R/C's before the balast resistor? can't be more noisy than the 580V since is would be a dublicate of what is going on there ...or do I completely miss the point here?

what would be the downside of building the zener string from some values that have 280V and tap the NB from there using some r/c+r/c and a balast resistor? 130V + 150V + 150V + 150V = 580V 130V + 150V = 280V 100k/100nF + 100k/100nF + 5 4M7 as balast?