Lampizator question

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NO! This would be exceedingly dangerous. You need a transformer for isolation from the AC line. Should the line be reversed for any reason or neutral goes open the chassis will be energized with possibly the full line voltage. Small inexpensive isolation transformers are readily obtainable on eBay and elsewhere. Further you will need filament power anyway.
 
Oh OK

Oh, ok.
The filament needs a decent current ? Not for heating element, see I have the 6.3v around, its the 110 I dont have.

Would a fuse or a zener diode work to isolate the thing ? I am just ignorant of the electronics behind much of this. Thanks for your help.
Thanks.
Srinath.
 
You want to build a tube device and have no experience in electronics... I would say that you have zero chance to have it working properly.
Try to replace the OpAmps on the players output, maybe the capacitors - something closer to your expertise.

Should the line be reversed for any reason or neutral goes open the chassis will be energized with possibly the full line voltage.
Well, in US we have the polarized plugs so the eventuality that neutral and hot get reversed "accidentally" is zero. Also, if he uses the ground to connect the chassis, the most it can do by reversing the hot and neutral is a short circuit. And even if it doesn't ground the chasis, that would be already grounded in his device. And last... it's just 120V, not like in EU 240V.
 
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Well, in US we have the polarized plugs so the eventuality that neutral and hot get reversed "accidentally" is zero. Also, if he uses the ground to connect the chassis, the most it can do by reversing the hot and neutral is a short circuit. And even if it doesn't ground the chasis, that would be already grounded in his device. And last... it's just 120V, not like in EU 240V.

:cop:

:attn: You're making several assumptions, all of which are deadly dangerous. There is NO SAFE WAY to do a direct connection to the mains, and it endangers not only the fool who tries it, but innocent people who happen to unknowingly touch the wrong thing at the wrong time. That's why we have a rule at diyAudio that direct mains connections are the only technical topic which may not be discussed.
 
You want to build a tube device and have no experience in electronics... I would say that you have zero chance to have it working properly.
Try to replace the OpAmps on the players output, maybe the capacitors - something closer to your expertise.


Well, in US we have the polarized plugs so the eventuality that neutral and hot get reversed "accidentally" is zero. Also, if he uses the ground to connect the chassis, the most it can do by reversing the hot and neutral is a short circuit. And even if it doesn't ground the chasis, that would be already grounded in his device. And last... it's just 120V, not like in EU 240V.

I built one as a complete beginner & it worked except I could not get rid of the hum, although you couldn't hear it when playing I knew it was there which annoyed me enough to rebuild it three times to try & remove the noise. finally on the third rebuild I killed the PCB somehow:D.

Also because I have sensitive speakers & the tube picks up every little thing I did end up with the odd noise in the music. hile it was working it sounded great.

David
 
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Well, in US we have the polarized plugs so the eventuality that neutral and hot get reversed "accidentally" is zero. Also, if he uses the ground to connect the chassis, the most it can do by reversing the hot and neutral is a short circuit. And even if it doesn't ground the chasis, that would be already grounded in his device. And last... it's just 120V, not like in EU 240V.

I respectfully disagree on all three counts; Most cheap cd players have class 2 insulation and two wire line cords, I've encountered outlets with open neutrals in my own house, and I have also encountered outlets with hot and neutral swapped in various situations. Accidents can and do happen, ask any electrical inspector. Any of these combinations under the right conditions could be lethal.

This guy is a newbie and doesn't understand the need for a power transformer - until he does he shouldn't be messing around with anything mains operated IMHO.

I'm not scared of 120V mains either, but I do know largely what I am doing...
 
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K I may have over pornounced my ignorance.

I have about a dozen amps, cd players and other general electronica fixed by basic trouble shooting and some very tricky replacements of components. I've done some serious amps by means of looking into schematics and troubleshooting. I also have built a few chip amps out of kits etc. So having said that ... I am pretty sure I'd get it done without really screwing up. The question was if the trafo is needed. My skill is pretty much where I can get it done ... if it works.

The inline GFI line is fine, I also have the cd player on a GFI strip, and it has a polarized plug. Its a kenwood cd player, but its also weighs 35 lb has a 7 cd capacity, and it has a tda 1541 dac. It was made and bought new in 1992/3. I also have a sony that has 1 cd capacity and weighs 40lb. Also with the tda 1541 dac. I wanna do the tube-i-zator in it cos its better for music. The DVD player is getting a fet mod. Its better for voices.

Cool. Srinath.
 
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Srinath, the fact that you need to ask whether a transformer is needed tells me at the least you should read the safety thread in the tubes forum. It's a fundamental safety issue that you don't quite seem to grasp (yet), and I'm sure you will.. It's just that I don't want you or someone else to get hurt in the mean time so don't take it the wrong way please.

Brdgs, Kevin
 
I am using some of the lampizator designs in current project and so far am satisfied with results. Having built valve amp previously and modded various bits of kit I am reasonably happy with my abilities, safety kit and approach. However caution is something am keen on being a rank amateur so could do with reading the safety thread myself - if I could find it..... where is it? Out of interest why does a tranny make things safer? There's still enough power in a valve amp to kill a herd of horses.
 
If you are using AC from wall socket then it is neccesary to have a transformer because your circuit like dvd player only needs 5v - negative 28V for display and it is easy to step down using coils of wire to make tranny.At the same time as you know a transformer works by electromagnetic induction meaning the primary coil does not need to touch or make contact like wires to complete an electrical circuit.This is what is called isolation.It's like you have flu and you don't want to pass it to your wife so you sleep in the next room.:D another way of saying isolation.;) or simply separation or put a distance from... something "dangerous".:p With regards the high voltage in a tube amp that's another story which is one that you are fully aware and alert that you know that high voltage can give a nasty shock or kill so you treat it with proper respect and not be foolish to disregard or dismiss the potential danger.

Regards.
 
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Allied electronics. Thanks.
I have a few trannies here and there from DOA amps. I am tempted to use them, though they all look like they would stick out 3 inch over the top of the player - which in my situation is a no no. I dont have rack space for that. The cd player has to get modded and still have the exact same exterior size/shape dimensions.
Cool.
Srinath.
 
Its been a long time, in fact I have had no audio related fun for over 2 yrs.

I did a fet mod that I put onto the opamp and didn't do any trafo for that.
It gave me better and sharper sound if I recall, but also induced some hiss. I repeated that mod to a onkyo 6 cd player and I don't remember what happened but that CD player died and - well I tossed it or something and gave up on it.

Thanks.
Srinath.
 
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