Poll..anyone interested in an Aikido linestage PCB group buy?

[Bas Horneman]

Try a 0,22uF or something as C1 (With 600V rating). If you have a couple of 0,22uF or something. Start with that and keep adding until you have the required voltage.

Remember that your psu needs to be connected to a working circuit. Otherwise there is no current draw and therefore no voltage drop over the choke and resistors.

Kind regards,
Bas

 

[Bas Horneman]

I have (2) 10 watts resistors, is this okay?
Then to confirm, I just hook them to the (2) filament wires and to the Heater Bias point?
thanks guys

10 Watt resistors are fine. But waaay overspecced. 1 Watt is sufficient.

Hook them up to the filament wires...and where the 2 resistors are connected...that is the part that you should connect to the heater bias point.

 

[nvrgdenuf]

Thanks Bas!
Another Q? When using a separate transformer for the Aikido tube heaters (which I want to run AC) it is a center tap, would I also hook that to the same heater bias connection point as the resistor ends of the other one?
Thanks in advance for your assistance!
andy

 

[Bas Horneman]

When using a separate transformer for the Aikido tube heaters (which I want to run AC) it is a center tap, would I also hook that to the same heater bias connection point as the resistor ends of the other one?

That is correct.

Thanks in advance for your assistance!

You are welcome.

 

[nvrgdenuf]

Thanks Bas,
In an OT, how do you like that tube x-over on you site? I looked at one from Marchand and the $$$ makes it unrealistic.
thanks

 

[Bas Horneman]

In an OT, how do you like that tube x-over on you site? I looked at one from Marchand and the $$$ makes it unrealistic

I never got around to building it. You can have them for free if you like. Just mail me your address. And I'll try to find them in the mess I call my "workshop" and I'll send em.

 

[nvrgdenuf]

Sent you an email Bas, THANKS!
andy
and if you need any aleph boards from briangt, I have several of those.

 

[Burnedfingers]

Would it be possible to use a 5Y3 in place of the 6X5 if you put a jumper from pin 3 to pin 4, pin 5 to pin 6, and pin 7 to pin 8?

 

[nvrgdenuf]

high voltage

Hi Bas,
I now have a total of 128uf attached to C1 which has lowered my voltage to 342 volts. The Hammond is rated at 275-0-275 but I am getting 304-312 volts from it. Any more recommendations to lower it to 300 volts? More capactors? Different transformer?
thanks for your help.
andy
p.s. just to add that it is measured while running the aikido which then runs a Pass F4.

 

[Bas Horneman]

Hi Andy,

128uF is a lot for c1. Have you tried something like 0,22uF. That is bound to lower the voltage.

Regards,
Bas

 

[kvardas]

I am using a center tapped transformer, such that I do not need D1 and D2 diodes. Should I use jumpers for D1 and D2, or leave empty?

Thanks

Kris

 

[maxdd_nj]

see above post...

http://www.diyaudio.com/forums/showthread.php?postid=1457773#post1457773
Looks like no jumpers are needed.

 

[kvardas]

I think I made a serious error. To allow the PSU PCB to be mounted such that I could read the connection labels from under the bottom of the preamplifier chassis, I mounted the 6x5 rectifier tube socket to the bottom of the PSU PCB, such that the top of the PCB faces down, while the tube socket faces up. As such, the tube is reversed. I presume this will cause it to not work properly.

Is that the case?

Thanks

 

[Bas Horneman]

Hi Kris,

Unfortunately that is the case.

Pin one will be in the place of pin 8...etc..etc.

I've made the same mistake before on a different pcb. Soldering the transformers to the wrong side...took a while to loosen.

The pcb I made a mistake on had metalization all the way trough the hole. (Not sure what the proper term is)

In the case of your pcb. Try not to heat the solder too long otherwise the pcb tracks may come loose.

Kind regards,
Bas

 

[kvardas]

I received my custom transformer with the following specs:

Output 1 - 0-290 V 50mA
Output 2 - 3.15-0-3.15V, 2A
Output 3 - 3.15-0-3.15V, 2A
Output 4 - 0-6.3V 1A

I will connect the heater bias to the CT of the two 6.3V supplies. The output 1 (high power supply) is not center tapped. I will use D1 and D2 diodes. Do I need to add two resistors to the high power supply? If so, what value? Also, where should I connect the two resistors?

Thank you

Kris

 

[kvardas]

Aikido up and running

I finally got my Aikido line stage up and running. Yah! I used the PSU PCB designed by Bas, used a choke, and a Heyboer transformer to run the PSU plus provide dual 6.3V heater supply.

The line stage sounds great. No coloration, bloom, or glare. Just clean, pleasing music.

Thanks all for the advise and insight.

Kris

 

[Bas Horneman]

Congratulations Kris!!!

 

[Renron]

Re: Aikido up and running

I finally got my Aikido line stage up and running. Yah! I used the PSU PCB designed by Bas, used a choke, and a Heyboer transformer to run the PSU plus provide dual 6.3V heater supply.

The line stage sounds great. No coloration, bloom, or glare. Just clean, pleasing music.

Thanks all for the advise and insight.

Kris

Kris,

Couple of questions for ya,
Did you use the default ratings on the PS board? ie: Caps / Resistors / Choke size?

Did you check your final voltage after it was completed?
Asking because most others have a 275 0 275 transformer and you stated you have a 290 0.
I've got a 300 0 300 ............just talking secondary HV.

Thanks,
Ron

 

[Renron]

Anybody try different size caps in C2 /C3 /C4 /C5 /C6 ?
I've got a few 68u I could substitute.


Is there a working PSUDII simulation of this board? Then I could manipulate the sizes myself. I got to the 5AR4GRAET Hybrid rectifier and C1 then Choke, 68uF cap then what?

Thanks for the help,
Ron

 

[Bas Horneman]

Anybody try different size caps in C2 /C3 /C4 /C5 /C6 ?

68uF would be fine. Since you have a choke. It's best to do your own psud simulation.