Hello Renron,
Please measure the voltage on the divider with the 47uF cap when you put on the amp. Than swap for a smaller size cap. You'll notice the difference.
Even with a slow turn on, which is actually a delayed upcoming of the high tension, loading the cap will be significant slower than the upcoming of the high voltage. Remember that an "empty" capactitor is like a sort of short-circuit, so the voltage on the divider will slowly rise to the wanted point as the cap gets filled. I've seen elevated heater supplies which took about 30seconds to reach the aimed voltage due to too large decoupling caps...
It's just meant to fine-tune the supply: It really is not a "bad design"! 😉
Please measure the voltage on the divider with the 47uF cap when you put on the amp. Than swap for a smaller size cap. You'll notice the difference.
Even with a slow turn on, which is actually a delayed upcoming of the high tension, loading the cap will be significant slower than the upcoming of the high voltage. Remember that an "empty" capactitor is like a sort of short-circuit, so the voltage on the divider will slowly rise to the wanted point as the cap gets filled. I've seen elevated heater supplies which took about 30seconds to reach the aimed voltage due to too large decoupling caps...
It's just meant to fine-tune the supply: It really is not a "bad design"! 😉
dhtrob said:
Tested voltage at the HT at turn on. With the uF47 cap it took ~13 seconds to reach 294V steady. As expected due to the valve warm up time.
Tested Bias at heater to chassis ground (NOT H-) and it came up to 104V.
Sorry, I'm not sure what exactly you would like me to measure.?
Before and after the cap replacement. Please be specific. I'm noob.
More than happy to measure and report back. Lemme know..
Ron
Hi guys,
I just got my Aikido kit 5687 and also Bas's psu today. Brilliant!
You are discussing this board at just the right time for me. So I see you are just using the B+right from the psu and emitting C5 and R3 as the 5687 board has just one B+ connection?
You are also using 2 transformers, one for the rectifier heater and B+, and the other for the 4 heaters(V1-4)?
I've got some 6N1P which I understand I can use for V2 and V3. And I need to buy some 5687's.
Cheers
I just got my Aikido kit 5687 and also Bas's psu today. Brilliant!
You are discussing this board at just the right time for me. So I see you are just using the B+right from the psu and emitting C5 and R3 as the 5687 board has just one B+ connection?
You are also using 2 transformers, one for the rectifier heater and B+, and the other for the 4 heaters(V1-4)?
I've got some 6N1P which I understand I can use for V2 and V3. And I need to buy some 5687's.
Cheers
Yup.
Yes again. But that is not necessary. If your 6,3V tap can supply enough current you can power all heaters from that tap.
Bas Horneman said:
Absolutely, I am using 2 tx because I was going to use a delay tube for the heaters then turn on the B+. Many people very experienced with tube amps and Preamps told me that with this voltage (~300) a delay was not needed. OK by me just that much easier to build my Aikido.
Ron
Thanks BAS ! Great PS board, works a charm.
The cathode resistors are R3/9 and 10??
What values do you recommend for 6N1P/5687 config at 300V B+?
Also 300V B+ is a good voltage to choose? or 240V standard?
Now to clarify some doubts I have:
I would use a tap of 12.6 V to supply the heater voltage on the main board.
The 6N1P draws 600mA right and the 5687 450 mA? So with 2 x 6N1P's and 2 x 5687's I would need min 2.1 Amps?
I would also need a second tap of 6.3V for the 6X5 rectifier? How many amps? Is this just 210mA?
What values do you recommend for 6N1P/5687 config at 300V B+?
Also 300V B+ is a good voltage to choose? or 240V standard?
Now to clarify some doubts I have:
I would use a tap of 12.6 V to supply the heater voltage on the main board.
The 6N1P draws 600mA right and the 5687 450 mA? So with 2 x 6N1P's and 2 x 5687's I would need min 2.1 Amps?
I would also need a second tap of 6.3V for the 6X5 rectifier? How many amps? Is this just 210mA?
Heater for the 6x5 requires at LEAST 600mA. @ 6.3V +/_ 10% ac or dc.
In the back of Broskie's guide he has recommended listing(s) for voltages of most tubes.
I would use a tap of 12.6 V to supply the heater voltage on the main board.?
Only if you have the board set up in serial configuration.
The 6N1P draws 600mA right and the 5687 450 mA? So with 2 x 6N1P's and 2 x 5687's I would need min 2.1 Amps?
Figure on the safe side for your TX at least 1.5 x 2.1
Ron
In the back of Broskie's guide he has recommended listing(s) for voltages of most tubes.
I would use a tap of 12.6 V to supply the heater voltage on the main board.?
Only if you have the board set up in serial configuration.
The 6N1P draws 600mA right and the 5687 450 mA? So with 2 x 6N1P's and 2 x 5687's I would need min 2.1 Amps?
Figure on the safe side for your TX at least 1.5 x 2.1
Ron
Latest revision to my sketch - some may find it helpful.
Thank you JPS!!!
I have been playing with PSUDII and with the following values:
C1=33uF
C2=180uF
C3=180uF
C4=47uF
6H 200mA 150ohm choke
R2/R3 = 1.8K 5W
I get a B+ of 255.3 Volts.
Thank you JPS!!!
I have been playing with PSUDII and with the following values:
C1=33uF
C2=180uF
C3=180uF
C4=47uF
6H 200mA 150ohm choke
R2/R3 = 1.8K 5W
I get a B+ of 255.3 Volts.
Hi,
I have a big doubt here. Maybe a dumb question.
We´re using DC for the B+ but for the heater supply?
Are you guys using AC or using another rectifier to convert the AC to DC for the heater 6.3/12.6V?
JB recommends strongly to use DC for the heater filamants or am I missing something big here?
I´m still a newbie to this.
Cheers
I have a big doubt here. Maybe a dumb question.
We´re using DC for the B+ but for the heater supply?
Are you guys using AC or using another rectifier to convert the AC to DC for the heater 6.3/12.6V?
JB recommends strongly to use DC for the heater filamants or am I missing something big here?
I´m still a newbie to this.
Cheers
Most are I think.
Does he? Are you sure it's not for a phono stage only? That is probably the only place where it is "strongly recommended" usually.
For 9 out of 10 situations AC is fine. Makes your line stage more robust. No rectifiers...no extra caps..no extra semi-conductors. Less stuff to go...kaput.
Bas Horneman said:
1) I'm using DC for JB's board heaters, bought the board from his tubecad website, makes the build that much easier......A/C for Bas' board heater
2) He does. Just one more thing to ensure there is no hum.
Please, don't beat me up on the A/C vs. D.C. thing here. It's easier for us newbs to screw up with AC, Ask C. Butterworth..or read his Aikido thread.
3) Your right, no doubt about it...but see #2 above.
Ron
Edited for name
Isn't D1 & D2 on the PS board for rectifying Heaters?
If D1 & D2 is not for DC heaters (they are for SS rectification of B+), I guess the 6X5 rectifier tube would not be required then...correct...
Either D1&D2 OR the 6X5 tube for rectification of B+...
If D1 & D2 is not for DC heaters (they are for SS rectification of B+), I guess the 6X5 rectifier tube would not be required then...correct...
Either D1&D2 OR the 6X5 tube for rectification of B+...
RockysDad said:
Bas Horneman said:
All your questions can be answered by reading through this thread again.
Not being rude, but that's how I found your answers above.
Ron
edited for spelleng
I have the 5687 Aikido board and trying to work out how to configure it to use the 6.3V 6N1P with the 5687.
I'm getting a quote on a transformer and need to decide whether I want 6.3 or 12.6V.
If I use 6.3V does this board allow me to set up the 5687 in parallel to get the 12.6V?
I'm struggling with this one.
In the manual it says to use 12.6V. I will set up the 6N1P in series to get the 6.3V right?
Brit01 said:
The way I read the manual is the 5687's must have 12V for V1 and V4. Then it is a question of V2 and V3. I am using a separate 12.6V xformer for the heaters so I will use J2 only to run in series for the 6CG7 tubes. If I were to use 12V tubes in V2 and V3 I would use jumpers J1 and J3 only to run in parallel.