ecc99 - 6C19n PP, (6S19P)

[Shoog]

I always implement a time delay on my +B which is a very simple little relay driver circuit. My approach is always to make everything as automatic as possible in order to avoid user error. One transistor, two caps and a few resistors is all it takes.
I have family who use my amp and they get annoyed enough with the complexity of my whole system to not be prepared to deal with two on switches. I even have it wired such that my Preamp on switch controls a none fused jumper mains lead to my power amp - that way one press and everything comes to life in a nice safe sequence.

Shoog

 

[piano3]

Hello Shoog,

Will the line hash still bleed through with the heater at an elevated potential?

Best wishes,N.A.

 

[Shoog]

Yes. It is an AC component so will be coupled by the transformer. It is the poor AC performance of EI's that makes them better at suppressing line hash.

Shoog

 

[tinitus]

hey, a redrawn schematic

just silly, but I thought it looked better this way 😛

 

[tinitus]

C3g

 

[tinitus]

ok
I have looked at Edcor trafos, and several others
ok prices, but shipping, custom and taxes eats on any bargains
I decided to better use the exstra expences to get better quality
or at least trafos with optimal specs

I contacted the Dutch trafo company AutomaticElectricEurope
by making it simpler I could get ok prices from them too
that means potted PP C-core OPTs without UL tap, and lowish powerhandling
multi tapped main supply trafo without heater winding
and center tapped 5A heater trafos with both 6.3V and 6V CT

regarding interstage Im in contact with Per Lundahl

I cant get any further until I have all trafos
due to long delivery time this thread may on hold for a while
maybe a month or two
as said, this is a winter project
and hopefully by then I may have forgot how much it costs 😛

see you later 🙂
cheers

 

[tinitus]

btw, am I right presuming that ripple voltage on each coil is about half of total, when series connected, as shown in schematic ?

I suppose that what is said in Lundahl spec sheet
quote
ripple voltage is approx. 0.42 x input voltage

http://www.lundahl.se/pdfs/datash/1685.pdf

though, I still dont know which to choose
I get a bit confused when it says recommended DC current
well, in my book it means the closer the better, or ?
maybe to load it better ?

any ideas which to choose ?

 

[tinitus]

hmm, I need to post this, so I dont forget it

C3g has huge gain in pentode
and only slightly less in UL
ok
I need to deal with that
looks like my IT may be something like 4:2+2
in other words, its a 2:1 step down configuration

and next move, away with cathode decoupling cap

additional info
http://www.diyaudio.com/forums/tubes-valves/174449-understanding-cathode-decoupling.html
http://www.angelfire.com/electronic/funwithtubes/Basics_05_Multigrid.html
http://www.diyaudio.com/forums/tubes-valves/149195-whats-advantage-e-linear.html

 

[revintage]

You need to load the C3g transformer secondary to make it work. Then Ra*Gm will be gain. Off course you also have to take the turns ratio in account when calculating. Ra should probably be something like 2-10k. Check the Ua/Ia curves!

 

[tinitus]

trying to understand

http://vrps.org/documents/Gm vs mu.pdf

http://www.tubes.mynetcologne.de/roehren/daten/as_triode_e.html

http://mysite.du.edu/~etuttle/electron/elect27.htm

 

[tinitus]

You need to load the C3g transformer secondary to make it work.

I remember you said that
but wont it upset the BlumleinGarter ?

I suppose the resitors of the BlumleinGarter needs to be taken into account too ?

 

[tinitus]

Revintage, we/you "found" a way to do the cross referenced BlumleinGarter with interstage

I can see why it was needed, with the relatively small resistor coupling

But if we look at Broskies active BlumleiGarter version

Resistors to ground are much larger
Wouldnt this not be exactly what we need, loading the IT secondary

or what am I missing ?

 

[tinitus]

looking at different bias, with CCS
I know it proably doesnt work, yet
but Im working on it

 

[tinitus]

or maybe somehing like this

man, this must seem more like poking around in a ** with a stick 😱 😛

 

[revintage]

Resistors to ground are much larger
Wouldnt this not be exactly what we need, loading the IT secondary

Wrong, they must be smaller (5-10k) to load the driver properly! Go triode and they should be larger.

 

[tinitus]

hey Revintage, nice to see you are still around

my latest version
I dont know, but I have a lot more variations
The last one I did twice, without knowing
but my first thought was hey, drawing the same schematic twice within minutes, without knowing, it could mean thats how it should be
but its probably just stupid, and I dont know for sure, as usual

whatever, trafos are still the same
and I cant do nothing but wait

In the meantime Im looking at the weird tube OPS JohnBroskie is doing right now
And he has promissed more on the subject tube OPS

 

[tinitus]

hey, I just got trafos, and shot a few pictures 🙂

 

[adamus]

try the d3a too, i think i prefer it to the c3g

 

[piano3]

Goodness,you had a long wait for these-you must be very patient. Looking forward to see project progressing.

Regards, N.A.

 

[tinitus]

thanks
yeah, and a bit more expencive than planned
sure hope I can make it work

but I need a little help
it confuses me with double secondary 😕
any of you know how to connect this OPT ?