[sdiy] Prebuilt bipolar 15v supply?

[Sam Ecoff]

Hi John,

On Oct 12, 2007, at 1:43 PM, John Luciani wrote:

> I am assuming that the power supply meets your voltage/current  
> requirements.

Voltage, absolutely... Ray says the sequencer will run successfully  
on anything from 9-15 volts. For most of his designs, he has posted  
typical current requirements, but not for the sequencer. So... this  
raises two additional newbie questions: 1. how does one go about  
figuring out the current requirement from looking at the schematic?  
2. Would it be reasonable to just purchase one of the supplies I  
think I'm going to use and try it and see if it works? (Given that I  
know the voltage is correct and the current is enough to power a  
typical module, is there a potential for damaging the unit? I don't  
think so, but then again, I'm still too new to really know....)

> The other disadvantage that you mentioned was the potential mixup  
> in the
> DIN connectors. You also need to verify that the lack of trimability
> won't be a problem
> with your load.

And again, this would be a matter of just trying it out? At only $20,  
I'm willing to pop for one and see if it works assuming that I'm not  
going to destroy anything.

> A couple more things to look at ---  Is there a minimum load?
> What is the response to faults like a short circuit. Make sure you
> select protection
> based upon the amount of current your circuit will draw.

Again, newbie mode <<on>>. Given a power supply like this,  http:// 
tinyurl.com/2238oa, how does one tell? Some of that info appears on  
the catalog page that links from the main page about this supply, but  
sadly, that supply isn't listed on that page.

O.k..... just called Jameco, I have some answers. First, the catalog  
# shouldn't be listed on that page since it's a web only item which  
doesn't appear in the catalog. Second, the person I spoke to was able  
to give me the minimum load info: 1 amp on the +12v line, 500 mA on  
the 12v line, and 3 amps on the +5v line. Given that I wouldn't be  
using the 5v line, this suddenly seems like a no go. Also... I don't  
know much about this, but it seems highly unlikely to me given what  
typical modules draw that the sequencer would draw 1 amp on the  
positive line.

So.... it seems like I'm sort of back to square one... phooey.

Thank you so much for sharing your time and knowledge, John. You have  
been most kind and patient!

Best wishes,

Sam E.