Try a Handmade Electronics H3007 (60H @30ma): they mate very well with the 12B4 and won't break the bank.
pm
Does anyone have a schematic of a tube regulator circuit for the 12b4?
I have 2 OA2 tubes on hand, can they be used?
Can anyone point me to the datasheet for the oa2?
Thanks
Lawrence
I have 2 OA2 tubes on hand, can they be used?
Can anyone point me to the datasheet for the oa2?
Thanks
Lawrence
Mark A. Gulbrandsen said:
Mark, do give the plate chokes a try. I have, and I ain't removing them anytime soon! I am using 100H 50mA. I have to add "wider and deeper soundstage" to what Zen_mod has mentioned too... 😀
I had a humming on one channel initially and just could not figure it out. Until I moved my PSU choke. Orientation didn't matter, physical distance did...
lawbadman said:
Are you going to use plate chokes? If you are, then you can use 1 OA2 on each side giving 150V regulation. If not, then you're going to need 300V and (recommended) 2 OA2s per channel (total of 4). Look for Zen_mod's schematic some posts ago...
I guess I dont understand how tube regulators work, but why would I need two per channel? Dont they work like zener diodes???
They do work like zeners.... You have to stack them in series to get the needed voltage.
I will try plate chokes as soon as time permits. The KSA-100 thread is comming back alive too and I have very limited time....
Mark
I will try plate chokes as soon as time permits. The KSA-100 thread is comming back alive too and I have very limited time....
Mark
lawbadman said:
One 0A2 with regulate to 150V, so to get 300V, you will need 2 stacked together as Mark mentioned. If you use plate chokes, you need only one for the required 150V.
On the topic of plate chokes, what are the sonic differences between a setup using plate choke and that which is using a OPT? I guess plate chokes still has the effect of the output capacitor, and higher output impedance?
Mark A. Gulbrandsen said:
Unlike Zeners they need a higher voltage to fire up, after that they drop voltage down to a regulated level. Slightly different resistors across them is the way to fire them up one by one and make resulting fire-up voltage less, if you connect them in series.
Wavebourn said:
Could you post a rough schematic? I wasn't aware that VR tubes needed resistors across them. I do know that they need a resistor above them eg.
http://www.tpub.com/content/neets/14178/css/14178_150.htm
Thanks
zobsky said:
Connect 2 gas tubes in series. Slowly rize voltage on them, of course through a current limiting resistor. Now connect pair of high ohm different bleeding resistors across them and compare. You may use a variac in the primary of your PT to check what voltage is needed to fire them up if you don't have a laboratory source of regulated voltage.
Alright, I will ask Zen Mod or anybody who can simulate this:
I bought a transformer just for this project to run those OO3 gas regulation tubes. Do I need a choke or filter arrangement for this transformer to run those tubes correctly???
Transformer: www.edcorusa.com Model: XPWR106
115V 60Hz. 275-0-275
125mA 6.3V, 4A
Primary Voltage:
115VAC
Primary Frequency:
60Hz
First Secondary winding:
275-0-275VAC, 125mA
Second Secondary Winding:
6.3VAC, 4A
http://www.edcorusa.com/classx/power/xpwr/Xpwr106.htm
I bought a transformer just for this project to run those OO3 gas regulation tubes. Do I need a choke or filter arrangement for this transformer to run those tubes correctly???
Transformer: www.edcorusa.com Model: XPWR106
115V 60Hz. 275-0-275
125mA 6.3V, 4A
Primary Voltage:
115VAC
Primary Frequency:
60Hz
First Secondary winding:
275-0-275VAC, 125mA
Second Secondary Winding:
6.3VAC, 4A
http://www.edcorusa.com/classx/power/xpwr/Xpwr106.htm
you bought it before you know it's good or not?LuckyLyndy said:
which schematic?
like Mark's -with R on anode?
preliminary - that xformer is on the edge here..... if I presume that you want R loaded stage,with two OD stacked per channel.....
Mark A. Gulbrandsen said:
in that case
xformer
then two schotkys (even from PC supply) as full wave rectifier ,common for both channels
then muuuucho of capacity
then same schmtc as for Mark's (one I drew it here..........http://www.diyaudio.com/forums/attachment.php?s=&postid=910671&stamp=1147048038
mebbe just slightly smaller resistor in front of gass toobz,just because your (Lucky's 😉 ) voltages will be smaller than 400V before gas stabz
anyway-I can bet that xformer will be warmmmmmmmmmmmmm
Mark-did you tried your super reg variant?
Not yet... time factor, time is a 4 letter word. Working on KSA-100 and then this 12B4 line stage or he is going to come to hunt me down!
Mark
