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In the Forum: Melquiades Amplifier
In the Thread: Bias help
Post Subject: Go after transformers maker.Posted by Romy the Cat on: 8/19/2013
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Well, they did not meet your specification, that is simple as that and they shall be taking care of all international shipping cost , import tax , VAT. I am a bit surprised as if it is more or less serious company then they shall not be able to miss the specs in this way. They clearly were trying to save money by making for you transformer with lover VA. What the scams, who those assholes are?

if you are with Lundhal 1627am /200mA  the n stay with your 180-190mA and run ~ 200-210V. That is if you need a full power. If you have very sensitive load to driver them you might not need it and might go for a half plate and use 150-160mA. The proper way to raise voltage of cause is by use of higher voltage transformer but if you do not have this option and if you use a very high volume of C10 then you might drop the volume of R22. If the C10 is too high then the C11 and R22 do not really do anything and you can bypass them. 200mA over 50R resistor will not give you too much voltage gain however.
 
The drift over +- 2-3mV is OK and it will go much better if you load your gas tubes harder – the gas tubes do not have good stability at 5mA. Still, if the 2-3mA are drifting very slow then it is not a big deal.
 
If you got screwed with transformer then there is some way to selvedge the project by introducing a very mild input capacitor before the input chokes. That will swing voltage higher but this also will/might have some sonic effect. I would not do it as you will always feel fucked and compromised.  I am sorry that the transformer situation had happened to you but I think you have very legitimate complain to the transformers maker.
 

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