Will this balanced PSU work as intended?

[Will]

Hi,
I'm having 2 of these stepdown transformers (240V to 120V) that do not have center tap, but I would like to derive balanced voltage output.

Will this arrangement work ? It will be used for a linestage pre-amp.




Thanks.

[CBS240]

Hi Will

How many volts do you need for a SS line stage pre-amp?

Much less than 170, I presume.

If you are using those high voltage empty glass thingies, you're in the wrong forum. (not that there is anything wrong with 'em)


You need a resistor voltage divider to set the floating GND potential on the caps halfway between +/-. Also, You could build an active floating GND. (current amplifier for the floating GND reference)

[janneman]

Originally posted by Will
Hi,
I'm having 2 of these stepdown transformers (240V to 120V) that do not have center tap, but I would like to derive balanced voltage output.

Will this arrangement work ? It will be used for a linestage pre-amp.




Thanks.

Will,

You say you have two xformers. Why not put the primaries in series and use each secondary full wave rectification? You have then two voltages of about 40V that you can put in series with the connection point to ground, that are much lower and closer to what you will need. Or you can put the secondaries in series and use half-wave rectification.

Jan Didden

[Will]

Originally posted by CBS240
Hi Will

How many volts do you need for a SS line stage pre-amp?

Much less than 170, I presume.

If you are using those high voltage empty glass thingies, you're in the wrong forum. (not that there is anything wrong with 'em)


You need a resistor voltage divider to set the floating GND potential on the caps halfway between +/-. Also, You could build an active floating GND. (current amplifier for the floating GND reference)

Hi,
Yes it's used for a tube buffer linestage ala Joe Rasmussen's SLCF BUT the issue concern here is related to sand diodes




What values do you recommend for the resistor values to be at?

Cheers.

[Will]

Originally posted by janneman



Will,

You say you have two xformers. Why not put the primaries in series and use each secondary full wave rectification? You have then two voltages of about 40V that you can put in series with the connection point to ground, that are much lower and closer to what you will need. Or you can put the secondaries in series and use half-wave rectification.

Jan Didden

Jan,
If I have 2 of them in primary series, that should mean that both 240V primaries will receive 120V each, and hence each of the secondary will be at 60V, and with 2 transformers of secondary in series then I should have 60-0-60VAC right?


Cheers.