Built a custom D8B external power supply

[arjepsen]

I personally used a seperate 48V supply. I took it out again, because it gave some high-pitched whiny noise - and I didn't use phantom power anyway.

[RJH_MUSIC]

What are the ratings? 48v how many amps? Watts?

[arjepsen]

The one I tried was rated for 1.1A - but mind you, I didn't try it with anything needing phantom power...
I would try to figure out how much power you would need, if you use phantom power on all mic preamps, and then scale it up a bit for a safe margin.
But again, you might also want to give a thought on how to avoid noise issues - you might need some filtering between the different supplies.

[RJH_MUSIC]

I found a few on the internet but i need to be careful of Amperes and wattage. I see one for 4.3A but the wattage output is 203 watts and i thnk that is way too much. I have decided to rebuild the remote CPU into 2 separate boxes. GOing to mount the existing motherborad and componenets for the computer into a low profile jury rigged ATX rack case. I will have to obviosuly do some cutting of metal, but determined to do it.

Second, I am going to use the posts here to build a 1U rack console power supply. The other issue i need to solve is that i could use the rack chassis power supply to generate the +/- 12V but the Amp ratings are different. Was looking at a low profile or mini pwer supply but again amperes are are around 20 AMPs for a 300 watt power supply.

RJ

PS - Thanks for the info

[arjepsen]

just a note: the Ampere and Wattage rating are not something you "force" into the system - it's a rating of how much energy you can pull from the power supply.

[RJH_MUSIC]

Studying schematics ad service manual today and want to clarify what I said yesterday.

1. 12V PC Power supply handles main power and powers PC as well as main power distribution board +/- 5 V and +/- 12V
2. Power distribution board with fuses distributes AC mains to LPS-152, and Transformer
3. Transformer generates +/- 16 V on Linear Power Supply Board
4. ASTEC LPS-152 generates +5V
5. Linear Power Supply board regulates +/- 16V from Transformer (J-1), + 5V from LPS-152 (J-5 and J-6), and generates + 48V out on pins J1-6 and J1-7

[RJH_MUSIC]

on the Amperage and Wattage, that sounds like good news. I think what you are saying is that as long as the power supply generates the minimum AMPs needed for the circuit, I should be fine?

[arjepsen]

yup.

[RJH_MUSIC]

Thanks much. Does the same concept apply to the computer power supply? I am finding a lot of low profile atx power supplies online, but none so far match the ouput ratings of the existing power supply. I do not want to blow up the motherboard. I found one that is close but may not fit in a 2U rack case.

[RJH_MUSIC]

Getting my parts in the next week or so to do this build. Excited to get started. One question remains. In the d8b psu there is a circuit board just behind the Remote PSU that contains about 4 - 5 fuses on it. These are in line in from of the connections to the other power supplies, Linear Power supply, LPS-152 and transformer. In the picture posted here for the build, i do not see any fuses other than the one supplied in the power connector and wondering if I should add one. On that note, wondering if i can just use the one that is in the Remote CPU unit as is. Any thoughts?

RJ