Topic: Two devices of 1 tekkeon?

[tgakidis]

So I have a tekkeon on the way.  My question is can I build a spliter to run my v3 & pmd661 off of one tekkeon battery at the 6v setting?  Also can I run the pmd661 off of the 5v USB out on the tekkeon?  I will know soon enough when it's in my hands but just wanted to know if anyone has tried these possibilities.

Opps, the PMD-661 is a 5v Device.  Still would like to know if you can run two devices of the same voltage of of one battery with a spliter cable.

[fobstl]

I have the same question about running 2 devices off of a Wally World 9 volt. I'm wondering if I could run my EAA-PSP2 and Tascam DR-680 off of the same battery.

[page]

So I have a tekkeon on the way.  My question is can I build a spliter to run my v3 & pmd661 off of one tekkeon battery at the 6v setting?  Also can I run the pmd661 off of the 5v USB out on the tekkeon?  I will know soon enough when it's in my hands but just wanted to know if anyone has tried these possibilities.

Opps, the PMD-661 is a 5v Device.  Still would like to know if you can run two devices of the same voltage of of one battery with a spliter cable.

What's the mA draw on the pmd? (why not use the USB out if the PMD will function on 1mA) which would solve the problem. (ala V3 & MT2 off of the single battery)

[edtyre]

I run a V-3, AD2K+, R-44 and MT2 all off one Tekkeon 3450 double battery with a custom cable shoepsnbox made me.
All at 12 volts (the MT2 runs off the usb port) I have a 6 volt V-3, but Grace told me to run this way...just a little extra heat.

Get 5-6 hours with this setup.

At Mountain Jam, i ran just the V-3 and R-44 off of it and got 15 hours the first day!! Thats right, i taped from noon
till 3:00 am without shutting anything down. Nice!

[yug du nord]

At Mountain Jam, i ran just the V-3 and R-44 off of it and got 15 hours the first day!! Thats right, i taped from noon
till 3:00 am without shutting anything down. Nice!

Nice!!!  Was that with 2mics or 4mics receiving phantom?  Either way, that's great!

[edtyre]

At Mountain Jam, i ran just the V-3 and R-44 off of it and got 15 hours the first day!! Thats right, i taped from noon
till 3:00 am without shutting anything down. Nice!

Nice!!!  Was that with 2mics or 4mics receiving phantom?  Either way, that's great!

2 mics, phantom on the V-3, digi-in to R-44

[jibooer]

Ted, I'd go with the Tekkeon double battery idea, as long as you can make yerself a cable that will power the two as the USB on the 661 does not provide power. Just the single battery pack will power the 661 for 15+ hours.  In addition you'll never have to buy another battery! Maybe this can be a new custom GAKable?

[page]

Ted, I'd go with the Tekkeon double battery idea, as long as you can make yerself a cable that will power the two as the USB on the 661 does not provide power.

But will the 5v in on the 661 accept 1ma or less? If it requires 2ma (for example), then my idea of hacking a usb cable to go from the tekkeon to the 661 is shot as you'd just be getting 1ma out of it.

[tgakidis]

Ted, I'd go with the Tekkeon double battery idea, as long as you can make yerself a cable that will power the two as the USB on the 661 does not provide power.

But will the 5v in on the 661 accept 1ma or less? If it requires 2ma (for example), then my idea of hacking a usb cable to go from the tekkeon to the 661 is shot as you'd just be getting 1ma out of it.

The USB out of the tekkeon seems to provide enough power to run my 661 or R09-HR with one of my usb > "b" tip power cables.  I plan to do a longer test to make sure.

[SmokinJoe]

Normally, a gizmo with a 5V USB host port (such as a computer) can be expected to supply up to 500ma (1/2 an amp).  That is a published USB standard.  I've got a little battery brick with USB ports on it, and I use it to power an H120 or a MR1.  The recorders have their own internal battery so this brick "helps keep them charged."  When you boot up the recorder and the hard drive starts to spin up, it uses more than the 500ma (MR1 is quoted as more than 1 amp), but the recorder's internal battery makes up the difference in the short run.  If you have a device without an internal battery, and you are JUST running it off the USB port you have no built in shock absorber, and depending on the device you might exceed that 500ma rating and it might drop out.  Hard to know until you try it.

Then there is the whole "ground loop" consideration...  I see it mostly in industrial equipment.  I doubt it's an issue here, just pointing out that when you take 2 devices that aren't at a common ground, and you decide to tie them to a common ground, you create a potential problem (no pun intended).  This is the main reason I don't try to run different stuff off the same battery.

This is all generic, and none of this specifically pertains to the Tekkeon, but I expect the same rules apply.

[AHappyHourHero]

Joe brings up a valid argument about ground loops when running two devices from the same battery.  Once I got the Tekkeon, I immediately went to work on a Y-cable to supply power to both my 660 and h4n.  My goal was to leave the bulk of the rechargeable AA's at home, and un-tether myself form the battery charging electrician job.  I can confirm that in the case I have, there is ground loop noise, and quite bad.  I am able to cleanly power the two using the USB power option in addition to the DC switchable output, but as Joe also stated, the need to keep AA's in the units to act as a buffer is a precaution that I use.  Neither decks have a spinning HDD, so start-up current is not a major issue, but I do not want to test the circuitry too often.
Ted manufactures custom cables to support multiple units from a common external battery, using a black box in the circuit that I will assume is a form of isolation circuit to prevent the ground loop issues.  You can find his very professional cables on the Retail space thread on here.  I have seen Ted's work in person, as well as his new addition to the Stone Church (in pictures only so far), and can attest to his fine craftsmanship.  There is no worries in having Ted manufacture a cable for your equipment.  If I wasn't such a DIY guy, with a desie to learn new things, I would have had him build me one already
Best practices apply:  use balanced, shielded cables whenever possible, keep unbalanced as short as possible, check your battery voltages from time to time, and keep all hands in feet in the bus at ALL times.

[bobbygeeWOW]

I'll just chip in to say "what he said"
The right thing to do is isolate the two devices from each other.

...but when I first got my (ridiculously immortal) battery geek battery, I immediately hacked up a straight-up splitter cable and have been using it ever since with my v2 through several deck evolutions, running at 12v.

(The difference between a 6v and 12v grace pre is only what the low battery light is set to react to - v2/v3's run off anything from 6v to 12v and probably beyond.)

[taperj]

I have run a Korg MR-1(5V) off of the USB side and simultaneously run a mixpre on 9v off of the swichable side many times. This, I believe, also keeps them isolated. I would think you could run any 5V device off of the USB side and run whatever else off of the switchable side. This was done on a MP-3450, battery life is long.

edit: Ah, I see AHappyHourHero already mentioned this. My apologies for restating.

J

[jibooer]

I can confirm that running a UA-5 9v out tekkeon + 5v USB running a PMD-661 (24/48,coax) gives me over 7 hrs on a single, and over 15 hrs on a double, with no line noise that I can discern. The GAKusb makes it happen.

[DigiGal]

So I have a tekkeon on the way.  My question is can I build a spliter to run my v3 & pmd661 off of one tekkeon battery at the 6v setting?  Also can I run the pmd661 off of the 5v USB out on the tekkeon?  I will know soon enough when it's in my hands but just wanted to know if anyone has tried these possibilities.

Opps, the PMD-661 is a 5v Device.  Still would like to know if you can run two devices of the same voltage of of one battery with a spliter cable.

What's the mA draw on the pmd? (why not use the USB out if the PMD will function on 1mA) which would solve the problem. (ala V3 & MT2 off of the single battery)

Just checked this thread now...

The PMD661 itself is rated for 5 VDC at 1.4A which is 1400mA. 

The AC Adapter unit that Marantz included is rated for 5V at 1.5A which leaves room to spare.

I have run with a hacked USB to Marantz plug before but will stick to the Tekkeon cable to eliminate any potential limitations that could pop up from USB spec current limitations.

[H₂O]

There are a few issues that can arrise when running 2 DC devices off one power source:

1. Grounding Loops (already discussed) - when one device has a different grounding or negative voltage - this can cause current to flow in the wrong direction and potentially add noise or damage equipment - To resolve this you need to use a ground isolating DC-DC converter (typically a fly back converter) or build one yourself with the right controller and xformer. 

2. Ripple Noise - if one device has a noisy power supply and the other device does not have a very robust filtering network then noise may be induced on the other device.  - To resolve add filtering between sources (can be added indirectly by a Voltage Regulator or DC-DC Converter in between).

I would be willing to bet that what Ted's box is filtering is the Ripple Noise indirectly and not isolating a ground loop as ground isolation can be expensive especially at current levels to power a deck or pre-amp.
 

[page]

So I have a tekkeon on the way.  My question is can I build a spliter to run my v3 & pmd661 off of one tekkeon battery at the 6v setting?  Also can I run the pmd661 off of the 5v USB out on the tekkeon?  I will know soon enough when it's in my hands but just wanted to know if anyone has tried these possibilities.

Opps, the PMD-661 is a 5v Device.  Still would like to know if you can run two devices of the same voltage of of one battery with a spliter cable.

What's the mA draw on the pmd? (why not use the USB out if the PMD will function on 1mA) which would solve the problem. (ala V3 & MT2 off of the single battery)

Just checked this thread now...

The PMD661 itself is rated for 5 VDC at 1.4A which is 1400mA. 

The AC Adapter unit that Marantz included is rated for 5V at 1.5A which leaves room to spare.

I have run with a hacked USB to Marantz plug before but will stick to the Tekkeon cable to eliminate any potential limitations that could pop up from USB spec current limitations.

poo, that's too high then. So either split the big cable or get a second battery. bummer.

[audiosf]

Would the Tekkeon MP3750 work fine with a SD USBPre 2 and a Tascam DR680?

[jibooer]

That will certainly work, however keep in mind that the capacity is 4100mah at 12v which isn't an incredible amount of run time. http://www.tekkeon.com/products-mypall-specs.html. However, the extended power pack is available which could double your capacity. The usb power will draw a bit too.

[jibooer]

I can confirm that running a UA-5 9v out tekkeon + 5v USB running a PMD-661 (24/48,coax) gives me over 7 hrs on a single, and over 15 hrs on a double, with no line noise that I can discern. The GAKusb makes it happen.

Well that worked for the UA-5, but...I was experimenting last night with my new  Naiant Bigbox and tried running it via DIN-3 to a Tekkeon and 5v USB to a R-09HR with terrible results. The noise was ugly. I tried it this with two different Tekkeons as well. I also tried it with different voltages, and high and low power from the Naiant, but still sounded like crap.  Whether or not it is Ripple or Ground loop noise is unknown to me, but it ain't a good sound. Just thought I would share this finding with ya'll.

Separate power sources eliminated all problems, and I think the 20v option (low power) on the Naiant running the Tekkeon on a low setting like 6v will yield some killer recording times.

[jibooer]

Thanks Jon! Much appreciated! Suffice to say that I don't have any qualms about isolating the Naiant's power source, especially after hearing that god-awful racket.

Nonetheless, it is still good to know that it could be possible to run the Naiant and another device off the same battery provided that proper cabling is used.

[jibooer]

Point taken.

Furthur testing has been done, the original scenario was repeated (Tekkon 9v DIN-3 to Naiant and 5v USB to r-09hr), but this time, I ran line-in XLR to my pmd-661 which was running on internal AA's at the same time. I got the same noise on the devices. When the USB cable was removed from the equation, noise was gone.

Well, as far as this thread is concerned, maybe someone else can chime in who has had issues like this.

[Fried Chicken Boy]

Would the Tekkeon MP3750 work fine with a SD USBPre 2 and a Tascam DR680?

I think acidjack runs this exact setup from time to time.  Check with him to confirm.

It sounds like the Edirol is the device injecting noise then.

Like the R-44, I think the R-09/HR has reversed polarity on the DC input.  Would that, in itself, cause the noise?

I have run a Korg MR-1(5V) off of the USB side and simultaneously run a mixpre on 9v off of the swichable side many times. This, I believe, also keeps them isolated. I would think you could run any 5V device off of the USB side and run whatever else off of the switchable side.

Just stumbled across the following blog post/article (link below) about using a Tekkeon to power a MixPre and Zoom H4N at the same time.  Since the H4N runs off two AA batteries, I'm sure this can be applied to any other deck that also does: Sony M10, Edirol R-09/HR, Tascam DR-2D, etc.  And the author gave a shout-out to taperj and linked to TS.com, too.

Rewire a Tekkeon battery to power MixPre and Zoom H4N