Burning Amplifier BA-1

Switches things on and off again
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Hi Gyuri - my fault entirely, Mark pointed me to your post 2 days ago!

We will do everything we can to get you the boards, even take funds with WU!

I have a lot of experience with WU in the past - of note one time when I was stuck in the middle of Laos on a motorbike without enough money to buy petrol to the nearest ATM which was 600 kilometers away (there were only 3 ATM's in the country), or to pay for the room I was staying in, or to pay to get back all my clothes which I'd got washed the day before losing my wallet. I think I had $2.50, and there was no such thing as a collect call, even collect calls cost 60c a minute from the "town telecommunication center".

If you can get us some USD, we'll work it out. Mark's sent you the details.

Summary - we don't normally accept WU but will rise the occasion if it's a genuine need and you don't mind covering all the sending costs (which are right up there!).
 
Thank you very much, guys!

This helped to smuggle some happiness in my life.
It could not be too comfortable in the Laos case.
Of course, the expenses incurred on me.
And I try to look into that, anything I can do so in the future (because the future will be) the future projects to be made by PayPal.
I remember my poor son is helped me to discuss with Steenoe at the time of delivery the LU1014-ers.
Payment happened with WU, and it was not so easy, because they are mixed with the reference numbers. Finally succeeded. Thanks, Steenoe!
Moreover, recently I finished my ZV9.
Maybe I can show it here, if someone is interested.
The deepest reverence:

Gyuri
 
Switches things on and off again
Joined 2000
Paid Member
Just to mention something which is not entirely obvious (because they want you to sign up for paypal), but you don't need paypal - just a credit card (visa, or mastercard).

For all card payments or bank transfers click "Continue" where it says "Don't have a PayPal account? Use your credit or debit card to pay". That may of course be disabled for some countries...

Thanks!
 
Thank you for the tip, Jason!

I have completed the process will, it seems to have succeeded.
I think I will get the feedback.
If this works, do not have to bother my poor Variac.
Who would otherwise thank you very much for your help, as well as yours, my dear Jason!

You guys are great!

Gyuri
 
Yesterday I got the boards::D

BA1&BA2 - Windows Live

Thank you for all you guys!:)
I do not know when these boards will be ready amplifier.
Indeed, while somewhat unexpectedly robbed me.:mad:
The tax office was the culprit.:(
I am slightly underestimated their expected prey.:eek:
So, not only that I had no money, but a substantial debt was incurred.:eek:
While we practically destitute.:h_ache:
But at least the outgoing government will be sufficient severance pay.:devilr:
Then, we earn the next. ::crazy:
I do not know, this was just now the forbidden politics?:rolleyes:

Gyuri
 
Member
Joined 2006
Paid Member
BA-1 backend

Well, I got the follower up and running with two FET's. Seemed pretty simple to get rid of DC offset like this, but I didn't have it powered up too long.

Well and without the gain board there is not much gain.:p
 

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I think lowering C203 will act as a high pass filter. But I am unsure of the Resistor value associated with it, possibly R14. I was shooting for 180-200hz for my lowthers.

Popped a Semisouth into the Q101 position, and was able to stablize bias with the fixed Q102 .6v.

Time to get a front end built.
 
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Joined 2009
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.....some news building BA-1! :sax:

My outputstage is only 3 devices deep, so I took 0,47 Ohm as a source resistor.

The voltage over the source resistor must be in my case only 0,3 Volt?
To get the bias current down, I had to start at 22 k with R 219 instead of 47 k.

I had some difficulties when setting the amp under fire, for instance I could not regulate the DC output to 0 Volt.
Later I remarked the holes to fasten the board have a very small distance to the voltage rails. My metal screws and the counterpart shortened something.
I would suggest for the second version of the boards to enlarge the distances or .... you use nonmetal parts to fasten the board.

The sound? (only the outputstage driven by pumpkin directly):

very good! really still better than F4 in many aspects, but less dynamics! (hi ZenMod:wave2:)

4 Ohm loudspeaker! Mister Nelson:cool: was right, sonically more pure, but more suited for impedances at 8 Ohm.

Nevertheless I will hear the next days BA-1! Returning to F4? Don´t know yet!

Maybe J2 is coming?:)