What happened me was during my build of SYs red district EL84 amp. I was using one of those transformers for the B+ - the heaters and a second B+ were coming off a different Tx.
What was happening was that the voltages were all over the place. I'd hook up one of the transfomers and get the right voltage, attach it to the circuit and it would be way off. Really difficult thing for someone inexperienced to figure. Anyway, thanks to shoog - he copped it right away. Once I replaced it the thing worked pretty ok. I think it was saturation or overloading or something (even though the current draw was very small - 10mA or something).
The ones I bought were supposedly pulls from working equipment - and in fairness the seller sent me 2 more to replace the first 2 ones which were bad - but they were bad too.....
I only mentioned it when I saw your pic of the Tx and thought oh oh! Look yours may be AOK.
To be honest I would like to hear a high voltage aikido as both of mine are the 24V type with 6GM8. These sound really good and yes, they have been put up against some really good gear and with a variety of experienced ears too.
If the worst comes to the worst, you might be able to get a 9V Tx and rectify and drop the voltage and run the heaters off that and a simple isolation transformer for the B+ - the one from a junked PC power supply might just do the trick. Ususally bathroom strip lights (ones with a shaver socket) have 20VA isolation transformers that could be pressed into service too. Not the highest quality, but they would allow you to get the thing working until you found something better.
Good luck with the build!
Fran.
ps somehow snag yourself a nice cap for the output position - a nice PIO or blackgate etc would be nice there.
What was happening was that the voltages were all over the place. I'd hook up one of the transfomers and get the right voltage, attach it to the circuit and it would be way off. Really difficult thing for someone inexperienced to figure. Anyway, thanks to shoog - he copped it right away. Once I replaced it the thing worked pretty ok. I think it was saturation or overloading or something (even though the current draw was very small - 10mA or something).
The ones I bought were supposedly pulls from working equipment - and in fairness the seller sent me 2 more to replace the first 2 ones which were bad - but they were bad too.....
I only mentioned it when I saw your pic of the Tx and thought oh oh! Look yours may be AOK.
To be honest I would like to hear a high voltage aikido as both of mine are the 24V type with 6GM8. These sound really good and yes, they have been put up against some really good gear and with a variety of experienced ears too.
If the worst comes to the worst, you might be able to get a 9V Tx and rectify and drop the voltage and run the heaters off that and a simple isolation transformer for the B+ - the one from a junked PC power supply might just do the trick. Ususally bathroom strip lights (ones with a shaver socket) have 20VA isolation transformers that could be pressed into service too. Not the highest quality, but they would allow you to get the thing working until you found something better.
Good luck with the build!
Fran.
ps somehow snag yourself a nice cap for the output position - a nice PIO or blackgate etc would be nice there.
Brit01 said:
Hi Chris!
John Broskie offers boards for both octal tubes, and 9-pin!
6N1P is a 9-pin tube. Choose boards for 9-pin tubes if you use 6N1P
About the power transformer: Some transformers can be wired for both 110V and 220V
This might be good choice if you want to use it in both 110 and 220V countries!
On the secondary you will need a 6,3V winding for the heater. One 6N1P draws 0.6A. Four of them = 2,4A
Choose a transformer that can deliver some more current! 4A or more should be good i think...
Then you need a winding for the anode voltage!
Some transformers are center-tapped, some are not!
The power supply circuit (and board) decides which power transformer you need!
How is it designed?
Great info. Thanks Olle.
I will hopefully be getting hold of the psu by Bas Horneman designed for the Aikido Line stage.
I believe it is like the one here:
http://www.diyaudio.com/forums/showthread.php?s=&threadid=60585&perpage=25&highlight=&pagenumber=11
I will have to confirm once I receive it.
What I would suggest is something like 250V secondary with say 150mA current.
And as ollebolle says "Choose a transformer that can deliver some more current! 4A or more should be good i think... " for the 6,3V
Since the voltage in Uruguay is the same as in Europe...specify a 230VAC primary. So that you can use it in the UK as well if you ever move back there.
And as ollebolle says "Choose a transformer that can deliver some more current! 4A or more should be good i think... " for the 6,3V
Since the voltage in Uruguay is the same as in Europe...specify a 230VAC primary. So that you can use it in the UK as well if you ever move back there.
Hi Bas,
Thks for jumping in.
I didn't want to bombard you with questions to your personal email.
So I need a transformer: 230 VAC input(primary) with 2 outputs, one of 6.3V DC with 4 amps and the second output with 250V DC with 150 mA?
The anode voltage is the B+ voltage?
Sorry as you can see I have a lot to study but very little time at the moment.
Thks for jumping in.
I didn't want to bombard you with questions to your personal email.
So I need a transformer: 230 VAC input(primary) with 2 outputs, one of 6.3V DC with 4 amps and the second output with 250V DC with 150 mA?
The anode voltage is the B+ voltage?
Sorry as you can see I have a lot to study but very little time at the moment.
The 150mA is a little extra. With all 6n1p's you'll probably be closer to a total current draw of 30-40mA or so. (7-10mA per tube)
B+ is the power supply voltage. It comes from the old b for battery. Batteries were some of the first power supplies used with tubes.
The anode voltage is Va. It is the voltage across the anode measured from the cathode.
As you may or may not know between the b+ and the anode there often is a load in most driver stages.
This load is often a resistor but can also be choke/transformer or ccs.
So often from b+ -> resistor -> anode. If the tube is drawing a current is a voltage will develop across the resistor. In other words b+ is often much higher than Va.
B+ is the power supply voltage. It comes from the old b for battery. Batteries were some of the first power supplies used with tubes.
The anode voltage is Va. It is the voltage across the anode measured from the cathode.
As you may or may not know between the b+ and the anode there often is a load in most driver stages.
This load is often a resistor but can also be choke/transformer or ccs.
So often from b+ -> resistor -> anode. If the tube is drawing a current is a voltage will develop across the resistor. In other words b+ is often much higher than Va.
Here is an excellent primer to brush up on your tube electronics
http://www.basenjes.de/tubes/data/neets_ch6.pdf
PS...this is not to prevent you from asking questions...but something you could download and peruse every now and then...in between c# courses
http://www.basenjes.de/tubes/data/neets_ch6.pdf
PS...this is not to prevent you from asking questions...but something you could download and peruse every now and then...in between c# courses
Hi Bas/Olle,
I've seen this new power board from JB:
http://glass-ware.stores.yahoo.net/hps1.html
Would this match well with the Aikido 9 pin stereo kit?
6.3 V right?
Thanks
I've seen this new power board from JB:
http://glass-ware.stores.yahoo.net/hps1.html
Would this match well with the Aikido 9 pin stereo kit?
6.3 V right?
Thanks
AFAIK,
you can use that board to give you any voltage upto the limit of the LM317. I use one to give me 25V for my 24V aikido. Yes, you could use it for the heaters - but you're looking at an amp or so total IIRC. The parts might need to be adjusted to give you the correct output range though. I would have thought that something simpler would do for heaters though....
Its a nice board, with facility for cap bypasses on the diodes and nicely built.
Fran
EDIT: I see he says its good for upto 2.5amps!
you can use that board to give you any voltage upto the limit of the LM317. I use one to give me 25V for my 24V aikido. Yes, you could use it for the heaters - but you're looking at an amp or so total IIRC. The parts might need to be adjusted to give you the correct output range though. I would have thought that something simpler would do for heaters though....
Its a nice board, with facility for cap bypasses on the diodes and nicely built.
Fran
EDIT: I see he says its good for upto 2.5amps!
Aikido are out of stock for the 9-pin stereo kit.
But they do have the 5687 kit.
Any opinions on this for a newbie?glass-ware.stores.yahoo.net/aiam56stkit.html
But they do have the 5687 kit.
Any opinions on this for a newbie?glass-ware.stores.yahoo.net/aiam56stkit.html