Topic: feeding 5V gear with 9V batteries?!

[sunjan]

I got thrilled reading deadheaded's post about powering his MR-1 with a 9V wally world batt:
http://taperssection.com/index.php/topic,125404.msg1666951.html#msg1666951

If the MR-1 can take 9V, maybe there is other 5V gear that can also be "over-powered" the same way?
That would make the powering a lot easier for other portable gear (iriver, JB3, EMU 0404 USB etc etc)

What would be the best method to test this?
deadheaded just took his chances and connected it - win or lose - but maybe there is a more scientific approch?

Looking at the guts or the circuit diagram of various gear, is there any way to spot if it's more forgiving to high voltage, or whether it would fry?
Would it make sense to connect a steppable AC/DC transformator at home, just go gradually upwards from 5V-6V-7.5V-9V and notice the behaviour of the gear in the mean time.

Any other ideas?

[JasonSobel]

In general, I don't think it's a good idea.  there was a post about someone powering their PMD-661 with 9V (it wants 5), and thought it was fine throughout a whole show.  at the end of the night, the deck was wicked hot.  too hot to pick up or touch.  all that extra voltage will get converted to heat, and I think he had to send the deck back to oade for repairs because something had fried on the inside.  I'm sorry I can't find the exact post now, but it's somewhere in the PMD-661 threads (either in the team boards or the two long threads in the recording gear section).  so, to sum up, while it may work for some gear, I wouldn't risk sending any other voltage to a piece of gear other than what is specified.  it's easy to enough to find a power solution that meets the specs exactly, so why bother?

[mtokheim]

how about just building yourself a cable using one of these in a project box:

http://www.lightobject.com/7805-5V-Regulator-P90.aspx

http://www.lightobject.com/Universal-DC-Power-Regulator-P112.aspx

then you can avoid any problems altogether!?

just a thought?

[cottle]

In general, I don't think it's a good idea.  there was a post about someone powering their PMD-661 with 9V (it wants 5), and thought it was fine throughout a whole show.  at the end of the night, the deck was wicked hot.  too hot to pick up or touch.  all that extra voltage will get converted to heat, and I think he had to send the deck back to oade for repairs because something had fried on the inside.  I'm sorry I can't find the exact post now, but it's somewhere in the PMD-661 threads (either in the team boards or the two long threads in the recording gear section).  so, to sum up, while it may work for some gear, I wouldn't risk sending any other voltage to a piece of gear other than what is specified.  it's easy to enough to find a power solution that meets the specs exactly, so why bother?

Yeah, that was me.  I can't remember which forum I posted it in, but I also would not recommend using more power than what the unit calls for.  Luckily it wasn't severly damaged, but had it run for another set or so, it could have easily fried the machine.  Turns out all I had done was overheat it, and the innards weren't compromised.  The AA's that were left in the deck expanded, and caused the battery compartment and cover to warp.  The battery connects were loosened, but Doug was able to glue in some spacers and get it working again.  We're still waiting for D&M to ship the replacement bottom case.  The unit works fine now, but every time I see that warped battery compartment, I'm reminded of my failure.  I've since invested in a Tekkeon, and it was money well spent.  In fact, I just got a $20 paypal refund from Newegg that I didn't even expect.