Thinking about providing 2 supplies from 1 tranny.
I can get a step down tranny 220/110 with 1000 watts supply.
Could I run ~120 volts 300mA and also a 25V 3.5 Amp from this 1 amp?
If I calculate correctly:
1000/110= 9 Amps available
How would I drop 110/120 volts to 25V to supply 3 amps from this tranny?
I use PSUII to do simple circuits but never attempted to take off a tap at a much lower voltage with much higher current.
I can get a step down tranny 220/110 with 1000 watts supply.
Could I run ~120 volts 300mA and also a 25V 3.5 Amp from this 1 amp?
If I calculate correctly:
1000/110= 9 Amps available
How would I drop 110/120 volts to 25V to supply 3 amps from this tranny?
I use PSUII to do simple circuits but never attempted to take off a tap at a much lower voltage with much higher current.
Thats a big transformer. You will get about 150-170V if you full wave rectify it.
To get the 25V at 3A you have several options:
(1) linear regulator = lots of power dissipation (maybe 500W continuous).
(2) Switching Regulator = better efficency with the risk of noise
(3) inductor input filter = lots of cost for the iron 20H 3A is a big choke!
Cheaper to get the right transformer(s) to begin with.
To get the 25V at 3A you have several options:
(1) linear regulator = lots of power dissipation (maybe 500W continuous).
(2) Switching Regulator = better efficency with the risk of noise
(3) inductor input filter = lots of cost for the iron 20H 3A is a big choke!
Cheaper to get the right transformer(s) to begin with.
Thanks Gimp.
There is also a 500w version. More manageable giving about 4.5 amps.
I can't get a 25v 3.5 amp tranny here.
Even difficult to get a 12V more than 1 amp.
Trying to see other options.
There is also a 500w version. More manageable giving about 4.5 amps.
I can't get a 25v 3.5 amp tranny here.
Even difficult to get a 12V more than 1 amp.
Trying to see other options.
What kind is this? 50 watts at 12V? that's 4 amps!
TRANSFORMADOR LAMPARAS ALOGEN DIMMABLE 240V AC, 12V AC - $ 80.00 - MercadoLibre
I see it is this type:
http://www.airlinktransformers.com/electronic-transformers.asp
I guess this is a big NO NO as its a hf electronic tranny.
TRANSFORMADOR LAMPARAS ALOGEN DIMMABLE 240V AC, 12V AC - $ 80.00 - MercadoLibre
I see it is this type:
http://www.airlinktransformers.com/electronic-transformers.asp
I guess this is a big NO NO as its a hf electronic tranny.
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In reading the second link, it appears that they are switching regulators that may operate all the way down to 10KHz. I would be concerned about coupling noise into the amp, but if they are operating up at 100KHz it might not be as much of an issue.
At that price I'd grab a couple. look at the output with a scope to see what the frequency is. If they are up in the 100KHz range it should be fine, you can always rectify it and regulate it with a 3-Terminal regulator to filter the noise.
Also just found a sale for 5 trannies , 28 v 3 amps each, for 35 USD all 5!
This could heat 4 x 6080 tubes in series with a little left over. I imagine I'll lose a little headroom.
This could heat 4 x 6080 tubes in series with a little left over. I imagine I'll lose a little headroom.
Would I be able to modify one of these to reduce it to 12 or 6 volts by unwinding?
Would it still maintain it's 3 amp rating?
Or is it easier to reduce 28v to 12 volts through a series of high wattage resistors or recitify and filter?
Would it still maintain it's 3 amp rating?
Or is it easier to reduce 28v to 12 volts through a series of high wattage resistors or recitify and filter?
If you are driving more than one tube, put them in series. Four 6.3V tubes will work on 28V with a small series resistor to drop the remaining voltage.
Or use a NTC thermistor to help hold down the inrush current and drop the remaining voltage.
Or use a NTC thermistor to help hold down the inrush current and drop the remaining voltage.
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