power transformer for C12 clone... which one?

[dmnieto]

I am building a C12 mic phone clone from scratch (without using a donor body), so I am trying to source a power transformer to fit in Dan's psu case.

The original alctron used a 220/110V primary to 200V/9.5V secondary, and I have not been able to find one like that. I would like to avoid having to buy two toroids (120V/9V and 12V/220V).

Does anybody know of any particular one I can use? It would be great if I could source it from mouser or digikey, but if they ship to the US for a reasonable price it will be fine as well.

 

[Woot]

I am in the same boat as you at the moment. I'll keep looking but interested to see what you come up with.

Matt  8)

 

[dmnieto]

I wonder if this one would be enough...


http://www.edcorusa.com/p/882/xpwr191

 

[poctop]

Look at Antek Toroid they multitap also
Best,
DAn

 

[dmp]

http://www.beesneezmicrophones.com.au/store/index.php?_a=viewProd&productId=114

 

[dmnieto]

I am looking at this one. I am not sure...
http://www.antekinc.com/as-05t200-50va-200v-transformer/

It should be enough to provide the 6.3VDC and the 120VDC, or not?

 

[dmnieto]

http://www.beesneezmicrophones.com.au/store/index.php?_a=viewProd&productId=114

Looks nice , wonder how much will cost to ship to US

 

[poctop]

I am looking at this one. I am not sure...
http://www.antekinc.com/as-05t200-50va-200v-transformer/

It should be enough to provide the 6.3VDC and the 120VDC, or not?

you could even tap the 2 * 6.3V to make out 12.6V so no worry .
Best,
Dan,

 

[dmnieto]

Call me mad, but tapping at 12V would mean that I would be dissipating a lot of heat on the heater regulator circuit

That is why I was wondering if the 6.3vac would be enough

 

[dmp]

Call me mad, but tapping at 12V would mean that I would be dissipating a lot of heat on the heater regulator circuit

The 6072 draws 350 mA at 6.3V (AC or DC). If you want to drop from 12.6 to 6.3 V, you would need ~18 ohms before the tube. Power dissipated in the resistor would be 2.2 Watts, same as the tube.
But you want to do some good filtering (that's the whole point of DC heaters), so you'd split that up, say three 6 ohm, 2 watt resistors with caps for PI filters inbetween.
So you would need some 2 watt resistors - not a big deal, you could even put in 5 watt resistors for not much more $.
If you want well filtered 6.3 vDC, you would want more than 6.3 vAC as a general rule of thumb. The more voltage you have to dump, the better you filter the DC.

Ohm's law V=IR
Power = VI

 

[dmnieto]

I ended up buying this one.

http://www.antekinc.com/as-05t160-50va-160v-transformer/

The 160VAC should give me about 225V rectified, which should be enough to provide the 120V on the rectification for the C12 and the 6072 B+

I'll tell how it goes