How to get +48V

Hi all,

I'm just messing about trying to build a basic mic amp, but I don't have a 48V supply for phantom - could someone point me in the right direction? I have a bunch of available voltages - 12 and 15 being the most robust - what simple solution is there? Preferably I'd like something I could assemble on a breadboard.

Any links to solutions for this, or advice would be great.

Thanks,

If you have access to the 15VAC you can use a voltage tripler to generate 45VAC, and then rectify and filter that into your phantom supply.

edit:  voltage tripler output _is_ dc, 60 some volts unloaded.  Sorry for my brain lapse.

dfuruta said:

If you have access to the 15VAC you can use a voltage tripler to generate 45VAC, and then rectify and filter that into your phantom supply.

Click to expand...

You could look at Gyraf's implementation in the G9 circuit. Its easy to follow. Bottom left corner of the schematic, where it says "Voltage Tripler".

http://www.gyraf.dk/gy_pd/g9/g9_sch.gif

You could replace the TIP121 portion with an LM337 for regulation, but there may be benefits to using the TIP121 I am not aware of.

In any case, this shows you a tripler at work providing phantom from a 15V supply source.

Gustav

Thanks for this example Gustav,I hope i'm not hijacking this thread but i'm looking for an example of dc doubler. I have a 24vdc
supply to power the modules and i'd like to generate  48vdc  for phantom . Many Thx

ubxf said:

Thanks for this example Gustav,I hope i'm not hijacking this thread but i'm looking for an example of dc doubler. I have a 24vdc
supply to power the modules and i'd like to generate  48vdc  for phantom . Many Thx

Click to expand...

You can see an example of a doubler for this same purpose in Keiths 9K PSU schematic/documentation.

http://www.studio21.ch/diy/neeno/ssl9k/DIY_9k_Preamp.pdf

Page 5. LM317 regulator.

I probably shouldn't recommend this as a read on the topic, since I dont fully understand it yet, but I haven't had a read through without gaining some insight yet.

http://www.electronics-tutorials.ws/blog/voltage-multiplier-circuit.html

Gustav

Thanks Gustav, much appreciated

> I'm just messing about

Many-many "Phantom" mikes will work fine with 12V or 18V Phantom.

My AKG 414s would work with 9V supply.

Yes, to handle "any" condenser mike the band drags in, 48V is wise. But for "messing about" you don't need it.

PRR said:

> I'm just messing about

Many-many "Phantom" mikes will work fine with 12V or 18V Phantom.

My AKG 414s would work with 9V supply.

Yes, to handle "any" condenser mike the band drags in, 48V is wise. But for "messing about" you don't need it.

Click to expand...

Messing about with the aim of not messing about eventually!

Thanks all, I'll go have a read.

The "doublers" Gustav is talking about work from an A.C source.
You can not "double" your 24v DC without using some sort of  switching convertor.

Maybe a "step-up" or "boost" dc-dc-converter could work: http://www.banggood.com/LM2577-DC-DC-Step-Up-Power-Module-3_5-35V-To-5-56V-Boost-Module-Red-p-89342.html

..but it would depend on actual noise and step-up abilities - I haven't tried it myself yet..

Jakob E.