Topic: Power-hungry V2?

[Sloan Simpson]

My 6-volt Lunatec V2 shut down after only about 3 hours of use last night. I assumed the battery had just died prematurely, so I switched over to a spare I had in my bag. Setting the battery to 6 volts, it would only stay on for a few seconds before the "low battery" light on the preamp would come on, and then it would shut down again. In desperation (I was missing the show!), I set the battery at 8 volts and it worked fine for the rest of the show.

Any ideas on what the problem is? Calibration on the V2? I checked the first battery when I got home, and it was showing half-full still. Am I subject to damage the V2 by feeding it 8 volts?

Thanks for any advice

[audBall]

Is it a Tekkeon battery?

The same thing happened to me so I switched the voltage setting to 7.5v and never had a problem after that.

[Sloan Simpson]

Is it a Tekkeon battery?

The same thing happened to me so I switched the voltage setting to 7.5v and never had a problem after that.

Yes, both batteries are Tekkeons (although different models). I was leaning toward it being a preamp issue, just because neither battery would run it at 6 volts.

[Brian Skalinder]

Vaguely recalling past discussions about running 6v V2s on 9.6v and 12v, including commentary from someone at Grace, I'm pretty sure you won't hurt your 6v-configured V2 running at 7.5v -- it will just generate a bit more heat.

I would guess the issue is due to possible voltage regulation imprecision by the Tekkeon.  The Tekkeon's voltage under load -- even when there's plenty of capacity left -- probably just drops below the threshold for which the V2 is configured to turn on the low battery light and to auto-shutoff.  Setting the Tekkeon to output higher voltage (e.g. 7.5v) will prevent the V2's low battery light from coming on and from shutting down automatically.  However, your V2 low battery light won't be a reliable indicator of remaining battery life (which it isn't now, anyway, so shouldn't really have an impact).

[Sloan Simpson]

Vaguely recalling past discussions about running 6v V2s on 9.6v and 12v, including commentary from someone at Grace, I'm pretty sure you won't hurt your 6v-configured V2 running at 7.5v -- it will just generate a bit more heat.

I would guess the issue is due to possible voltage regulation imprecision by the Tekkeon.  The Tekkeon's voltage under load -- even when there's plenty of capacity left -- probably just drops below the threshold for which the V2 is configured to turn on the low battery light and to auto-shutoff.  Setting the Tekkeon to output higher voltage (e.g. 7.5v) will prevent the V2's low battery light from coming on and from shutting down automatically.  However, your V2 low battery light won't be a reliable indicator of remaining battery life (which it isn't now, anyway, so shouldn't really have an impact).

Sounds good, thanks.

[page]

Vaguely recalling past discussions about running 6v V2s on 9.6v and 12v, including commentary from someone at Grace, I'm pretty sure you won't hurt your 6v-configured V2 running at 7.5v -- it will just generate a bit more heat.

I would guess the issue is due to possible voltage regulation imprecision by the Tekkeon.  The Tekkeon's voltage under load -- even when there's plenty of capacity left -- probably just drops below the threshold for which the V2 is configured to turn on the low battery light and to auto-shutoff.  Setting the Tekkeon to output higher voltage (e.g. 7.5v) will prevent the V2's low battery light from coming on and from shutting down automatically.  However, your V2 low battery light won't be a reliable indicator of remaining battery life (which it isn't now, anyway, so shouldn't really have an impact).

I agree.

I've used a handful of tekkeons with my 722 which has a voltage meter on it and while not all units, many do drop under load. I've seen as much as almost a full volt and as little as 0.1 or 0.2 volts. Of the 4 units I've tried, 1 maintained the selected voltage, the rest drooped a bit to varying degrees under differing loads. If you have a sensitive unit (the 722 switches over at something obscure like 9.75v), then a given battery may sag too much.

[F.O.Bean]

Yes, 7.5v is fine. I used 7.2v rc batts when I had my v2/v3 and they worked just fine

[Sloan Simpson]

Tonight it shut down again while I was running it at 9v  I turned it up to 12v and it ran for the rest of the show 

[Hypnocracy]

I run my 6v V2 for 4 day festivals solid with Tekkeons at 7.5v

Tonight it shut down again while I was running it at 9v  I turned it up to 12v and it ran for the rest of the show 

Having two Tekkeons failing is a stretch...but...The only other thing to do is try a friends Tekkeon at 7.5v...or it sounds like a call/trip to Grace may be in order...

[Brian Skalinder]

Again?  Ugh.  How long were you running at 9v before it shut down?  I wouldn't send the V2 off to Grace just yet, as in my mind we haven't determined the V2 is definitively the culprit.  While it's unlikely both Tekkeons failed at the same time in the same way (I've seen stranger things happen), we still need to attempt isolate each component in the chain with testing (as best we can) to find out where the problem lies.)  I would go about it in roughly this order:

• Are you using a single V2 power cable with both Tekkeons?  If so, check your power cable (between the V2 and Tekkeon(s)) for shorts / continuity.  (You'll need an inexpensive multimeter for testing, a tool all tapers should own, IMO.)  If there are any shorts, you've likely found the problem.  If you don't know how to do this testing, let us know and someone can help describe the process.  FWIW, I've seen shorts in cables before that aren't severe enough to shut everything down on the spot and flame out, but instead cause unpredictable behavior over time.
• If you have access to another power cable, test with the other power cable.  If the other cable works fine, then it's likely your original cable is the problem.
• Do you have a separate AC cable for the V2?  If so, try it -- see if it runs for a long stretch from AC or if it suffers from the same shutdown.  The AC wallwart converts AC to DC and provides a regulated DC voltage to the V2.  If this works fine, it suggests the V2 is not the culprit.  If the V2 still shuts off, it indicates the problem lies with the V2 itself.  If you don't have a wallwart, consider buying a generic one (they're fairly cheap) or borrowing one.
• Do you have access to another Tekkeon?  If so, try a friend's known-good Tekkeon to see if the problem repeats.  If the problem does not repeat, the Tekkeons are the likely culprit.  If the problem does repeat, the problem likely lies elsewhere.
• Do the Tekkeon's work fine powering other gear?  Try powering other gear to validate whether or not the Tekkeon's are okay (preferably, another V2).  If the Tekkeon's work okay with other gear (ideally with similar power draw, or for a sufficiently long period of time given the other gear's power draw), this suggests the problem lies elsewhere.  If the Tekkeon's have trouble powering other gear, they're likely the culprit.
• Consider testing the Tekkeons' voltage at intervals, under load, over a period of time -- say at 0min, 15min, 30min, 45min, etc.  This may provide insight into what is happening (e.g. is the voltage dropping off a cliff at a certain stage), which may help inform further testing.
  
• As a final consideration before sending the V2 off to Grace (which I wouldn't do until you validate the problem definitively lies with the V2), you might also try opening up the V2 and verifying the status of the 6v / 12v jumper(s).  Additionally, you could try turning the low battery / auto-shutoff calibration all the way down, so it takes the lowest voltage possible before the lighting up / auto-shutting off.  (Maybe a previous owners messed with them?)  Note:  this would render the low battery light and auto-shutoff unuseable in the field, but I don't know anyone who still uses these features with newer batteries, since they typically need to be re-calibrated for non-6v / non-SLA power sources.  There's a jumper diagram in the manual and instructions on voltage calibration on the Grace Design website.  (Though I have to say, it seems unlikely the voltage calibration is the culprit, but it's probably worth checking, even if not changing.)

FWIW, my money's on the cable.  Good luck and let us know what you find out, so we can help identify next steps.

[Sloan Simpson]

Again?  Ugh.  How long were you running at 9v before it shut down? Just a little over an hour this time. I wouldn't send the V2 off to Grace just yet, as in my mind we haven't determined the V2 is definitively the culprit.  While it's unlikely both Tekkeons failed at the same time in the same way (I've seen stranger things happen), we still need to attempt isolate each component in the chain with testing (as best we can) to find out where the problem lies.)  I would go about it in roughly this order:

• Are you using a single V2 power cable with both Tekkeons? Yes If so, check your power cable (between the V2 and Tekkeon(s)) for shorts / continuity.  (You'll need an inexpensive multimeter for testing, a tool all tapers should own, IMO.)  If there are any shorts, you've likely found the problem.  If you don't know how to do this testing, let us know and someone can help describe the process.  FWIW, I've seen shorts in cables before that aren't severe enough to shut everything down on the spot and flame out, but instead cause unpredictable behavior over time.
  
• If you have access to another power cable, test with the other power cable. A friend might, I'll need to check If the other cable works fine, then it's likely your original cable is the problem.
  
• Do you have a separate AC cable for the V2? No If so, try it -- see if it runs for a long stretch from AC or if it suffers from the same shutdown.  The AC wallwart converts AC to DC and provides a regulated DC voltage to the V2.  If this works fine, it suggests the V2 is not the culprit.  If the V2 still shuts off, it indicates the problem lies with the V2 itself.  If you don't have a wallwart, consider buying a generic one (they're fairly cheap) or borrowing one.
  
• Do you have access to another Tekkeon?  Maybe, will check. If so, try a friend's known-good Tekkeon to see if the problem repeats.  If the problem does not repeat, the Tekkeons are the likely culprit.  If the problem does repeat, the problem likely lies elsewhere.
  
• Do the Tekkeon's work fine powering other gear? Only other gear I have to try is my M10, they work fine with it. Try powering other gear to validate whether or not the Tekkeon's are okay (preferably, another V2).  If the Tekkeon's work okay with other gear (ideally with similar power draw, or for a sufficiently long period of time given the other gear's power draw), this suggests the problem lies elsewhere.  If the Tekkeon's have trouble powering other gear, they're likely the culprit.
  
• Consider testing the Tekkeons' voltage at intervals, under load, over a period of time -- say at 0min, 15min, 30min, 45min, etc.  This may provide insight into what is happening (e.g. is the voltage dropping off a cliff at a certain stage), which may help inform further testing. Will do
  
• As a final consideration before sending the V2 off to Grace (which I wouldn't do until you validate the problem definitively lies with the V2), you might also try opening up the V2 and verifying the status of the 6v / 12v jumper(s).  Additionally, you could try turning the low battery / auto-shutoff calibration all the way down, so it takes the lowest voltage possible before the lighting up / auto-shutting off.  (Maybe a previous owners messed with them?)  Note:  this would render the low battery light and auto-shutoff unuseable in the field, but I don't know anyone who still uses these features with newer batteries, since they typically need to be re-calibrated for non-6v / non-SLA power sources.  There's a jumper diagram in the manual and instructions on voltage calibration on the Grace Design website.  (Though I have to say, it seems unlikely the voltage calibration is the culprit, but it's probably worth checking, even if not changing.)

FWIW, my money's on the cable.  Good luck and let us know what you find out, so we can help identify next steps.

The cable seems like it makes sense, as it gets jumbled around in my gear bag and could've gotten damaged that way. I've been using the V2 for 10 years, the last 2 with the Tekkeons.  Thanks for your post, I've a cable-making friend I'll be looking at it with in the next few days. I've got another show tonight, gonna just set it on 12v at the start and hope for the best.

[page]

The cable seems like it makes sense, as it gets jumbled around in my gear bag and could've gotten damaged that way. I've been using the V2 for 10 years, the last 2 with the Tekkeons.  Thanks for your post, I've a cable-making friend I'll be looking at it with in the next few days. I've got another show tonight, gonna just set it on 12v at the start and hope for the best.

There are certain angles on my 722 cable that will cause the voltage reading to drop about 0.3v-0.5v or so on the read out.

[Sloan Simpson]

Battery A turned out to only be putting out .24 amps, while the V2 needs .48.  Battery B tests out fine, as does the cable, so I'm going to use Battery B going forward and see what happens.

Battery A is only one month out of warranty 

[F.O.Bean]

Battery A is only one month out of warranty 

Gotta love that when it happens

[Brian Skalinder]

Thanks for the update, SS.

While it sucks battery A is only one month out of warranty, at least you've removed it as a cause (or one of the causes) of your issues.  You might try calling in the warranty, anyway.  Some retailers / manufacturers are more generous than others when the warranty has only just expired.  If you do call it in, tell them you used it with a portable DVD player or some such.  They simply won't understand your usage and they may wrongfully assume you've misused the battery and then may not offer the 1-month extension of the warranty service (assuming they would have done so in the first place).

Please keep us informed on how your testing and usage goes with battery B.

[flipp]

Do contact Tekkeon. Their CS rep (I think Chris though with my memory I wouldn't bet on it) indicated their warranties aren't written in stone and they often extend it some. All they can do is say that it is out of warranty but it will only cost a bit of your time to see if it is still covered. One of mine was about three weeks out and they replaced it; had a new one out the same day they received the old one.

[Sloan Simpson]

Ugh.

Friday night: set up at a show with Battery B on the V2 at 6v. Only ran for a minute or so, the low-batt. light came on and it shut down  So something is bring besides/in addition to Battery A. I set Battery B to 12v, it ran for the rest of the night (about 2 hours).

Saturday night: started the show with Battery B at 12v, it shut down after 2.5 hours. Does running at 12v drain a battery that much faster than at 6v? I (obviously) know next to nothing about electricity. . .

Ended up fumbling back and forth with both batteries trying to get the whole show last night. Ended up with 3 cuts in my recording 

[audBall]

Bummer.  Is there a 7.5v setting on yours?  Regardless, I'd take the advice of contacting Tekkeon. 

[Sloan Simpson]

Bummer.  Is there a 7.5v setting on yours?  Regardless, I'd take the advice of contacting Tekkeon.

Both batteries do have 7.5v settings, but it shuts down quickly at that setting. 12v is the minimum that will keep it running for a while . . .

Starting to wonder if it's not Grace that I need to contact 

[F.O.Bean]

Hmmm, can you try the Tekkeons on anything else? Other gear? Do you have an old SLA 6/12v to run the v2 to see if it works w/ a NON-Tekkeon battery

[Sloan Simpson]

No, no other gear on-hand, and all my SLAs died long ago.

[jbell]

Could be a bad battery cable.

[Sloan Simpson]

Could be a bad battery cable.

My buddy who brought the multimeter over said the cable tested OK, but we're gonna get together tomorrow or so and try that again. That's the only other thing that makes sense to me, as the batteries are completely different models bought at different times, so I can't see them failing at the same time . . ..

[it-goes-to-eleven]

I'm betting on the battery cable having an intermittent short.  It is a common element in all of this, I recall.  And it has been described as being "jumbled around"....

When testing, I think you need to work it around, bend it, etc. You'll probably need a way to keep the probes firmly attached with some clips.

Can you post a pic of the cable?  Maybe we can diagnose it visually

[Sloan Simpson]

Cool, we'll have 4 hands when we test the cable so we can put the cable through its paces in the process 

[goodcooker]

Battery cables esp copper ones should be replaced every couple of years.

[tgakidis]

I'm betting on the battery cable having an intermittent short.  It is a common element in all of this, I recall.  And it has been described as being "jumbled around"....

When testing, I think you need to work it around, bend it, etc. You'll probably need a way to keep the probes firmly attached with some clips.

x2

[Sloan Simpson]

Anyone know offhand what the name of the connector is used to go to the Tekkeons? Gonna test out the cable tonight. Would just build a new one if we can figure out where to get that part. . .

[tgakidis]

Listed at the bottom of the first post in the thread.
 http://taperssection.com/index.php?topic=150794.0

The tekkeon web site sells straight and right angle cables for $8

[Sloan Simpson]

Listed at the bottom of the first post in the thread.
 http://taperssection.com/index.php?topic=150794.0

The tekkeon web site sells straight and right angle cables for $8

Thanks!

[Sloan Simpson]

Now almost positive the battery cable was the problem. I borrowed a friend's SLA and cable and run on it for four hours tonight without a shutdown.

[it-goes-to-eleven]

Cool...  That can be so frustrating.

I think many of us take our aging, years old, cables for granted.. Not just power, but audio.

It's always a good idea to once in a while do the "wiggle test" on all your cables with the rig setup and recording.. In the middle, on the ends, etc.  And then review the waveform for any blippage.

But sometimes too much heatshrink, etc, on a cable can actually make it more fragile than if it didn't have it (beacuse it can act as a lever and concentrate force). And a wiggle test may cause a cable to fail.

In your case you had a high current draw/short, so a wiggle test might not have revealed it.

[mepaca]

This http://www.ebtechaudio.com/swizzdes.html is a great $75 investment for anyone who works with audio.

[Brian Skalinder]

Now almost positive the battery cable was the problem. I borrowed a friend's SLA and cable and run on it for four hours tonight without a shutdown.

While it's impossible to definitely determine the battery cable is the problem - since the battery and battery cable were both swapped out at the same time -- I suspect you're right.  Cables are relatively cheap.  Have another made up and then try switching back to your Tekkeons.  I sure wouldn't want to keep using those SLA bricks!

[Sloan Simpson]

Now almost positive the battery cable was the problem. I borrowed a friend's SLA and cable and run on it for four hours tonight without a shutdown.

While it's impossible to definitely determine the battery cable is the problem - since the battery and battery cable were both swapped out at the same time -- I suspect you're right.  Cables are relatively cheap.  Have another made up and then try switching back to your Tekkeons.  I sure wouldn't want to keep using those SLA bricks!

Yeah, it definitely wouldn't pass the scientific method  I'm fairly convinced just because two different Tekkeons (different models bought at different times) failing at the same time blows my mind.

Gonna get a cable and hope to return the SLA ASAP! I frequently walk the few blocks downtown to tape shows with my rig, and that's not happening with the extra 10lbs or whatever it is 

[morst]

I had two SLA's fail after five years of use, and they failed within a few months of each other. These things don't last forever!

[F.O.Bean]

If you want, I have a brand new 6v/7.2a SLA that I got sent from B+H for free They missent it to me. But its yours if you want it!

[Sloan Simpson]

If you want, I have a brand new 6v/7.2a SLA that I got sent from B+H for free They missent it to me. But its yours if you want it!

Oh man, that's awesome of you to offer, but a friend gave me a SLA when this problem started, so I'm good. Thanks!

[Sloan Simpson]

The problem returns  Have been running a brand-new SLA for the last few weeks, with a newly made cable for it. At about 3 hours usage the other night I noticed the V2 had shut down at the end of the show. Turned off the power and then turned it back on successfully (only lost 1 minute of music this time). When I got home I tested the battery and it still showed mostly full 

It's failed with 3 different batteries and 3 different cables at this point, I'm thinking the problem is with the V2 itself. I'm not technically-minded, so this is really confusing me.

[jbell]

Might be time for a trip to Grace!! 

The problem returns  Have been running a brand-new SLA for the last few weeks, with a newly made cable for it. At about 3 hours usage the other night I noticed the V2 had shut down at the end of the show. Turned off the power and then turned it back on successfully (only lost 1 minute of music this time). When I got home I tested the battery and it still showed mostly full 

It's failed with 3 different batteries and 3 different cables at this point, I'm thinking the problem is with the V2 itself. I'm not technically-minded, so this is really confusing me.

[JD]

The problem returns  Have been running a brand-new SLA for the last few weeks, with a newly made cable for it. At about 3 hours usage the other night I noticed the V2 had shut down at the end of the show. Turned off the power and then turned it back on successfully (only lost 1 minute of music this time). When I got home I tested the battery and it still showed mostly full 

It's failed with 3 different batteries and 3 different cables at this point, I'm thinking the problem is with the V2 itself. I'm not technically-minded, so this is really confusing me.

I had a similar problem with my V2 a few years ago, it kept shutting down with almost fully charged 6v SLA's. After talking with a tech at Grace, it was determined that the V2 just needed to be re-calibrated.
They sent me a PDF with the process. Basically there was a couple of potentiometers inside that needed to be adjusted. I believe one set the low voltage threshold that would shut the unit off.

I'll look and see if I can find the PDF file for ya.

[JD]

Found it on their website..... http://www.gracedesign.com/support/v2_voltage_cal.pdf



Edit to add...They had quoted me a price to do the re-calibration, I do not recall how much it was, but I do recall thinking that it was a reasonable fee.

[Sloan Simpson]

Found it on their website..... http://www.gracedesign.com/support/v2_voltage_cal.pdf



Edit to add...They had quoted me a price to do the re-calibration, I do not recall how much it was, but I do recall thinking that it was a reasonable fee.

Thanks! I've got a buddy who's good with this kind of thing so I'm going to show this to him and see if we can DIY it.

[markrsmith]

I just sent mine in to Grace for 75$  plus 15$ s/h, and got it back in about a week.  They performed a bench test and calibration, also PSU update(whats that?), and electrolytic caps replaced...  They were very communictative and nice to deal with.  I bought mine used, and this made me feel better to get a clean bill of health. 

[Sloan Simpson]

I just sent mine in to Grace for 90$ and got it back in about a week.  They performed a bench test and calibration, also PSU update(whats that?), and electrolytic caps replaced...  They were very communictative and nice to deal with.  I bought mine used, and this made me feel better to get a clean bill of health.

Hmm, that's probably something I should do, but money's tight, so hopefully my buddy can get it working for me short-term, and I'll send it in for the full service later when I have more cash.

[drewloo]

Try running it w/ VR7 turned all the way counter clockwise.  This won't protect your SLA from going too low anymore but SLAs are cheap.  See how long it runs now.   

[Sloan Simpson]

Try running it w/ VR7 turned all the way counter clockwise.  This won't protect your SLA from going too low anymore but SLAs are cheap.  See how long it runs now.

That's an idea. I'm interested in switching back to the Tekkeons if I can, any idea if running that fully counter-clockwise would damage them?

[drewloo]

Try running it w/ VR7 turned all the way counter clockwise.  This won't protect your SLA from going too low anymore but SLAs are cheap.  See how long it runs now.

That's an idea. I'm interested in switching back to the Tekkeons if I can, any idea if running that fully counter-clockwise would damage them?

The Tekkeon probably has some sort of circuitry protection to protect itself but I'd check to be sure.

[Sloan Simpson]

Try running it w/ VR7 turned all the way counter clockwise.  This won't protect your SLA from going too low anymore but SLAs are cheap.  See how long it runs now.

That's an idea. I'm interested in switching back to the Tekkeons if I can, any idea if running that fully counter-clockwise would damage them?

The Tekkeon probably has some sort of circuitry protection to protect itself but I'd check to be sure.

Will do, thanks.

[Sloan Simpson]

Try running it w/ VR7 turned all the way counter clockwise.  This won't protect your SLA from going too low anymore but SLAs are cheap.  See how long it runs now.

One more thought on this, would I be at risk of damaging the V2 by doing this and then running low?

[JD]

Try running it w/ VR7 turned all the way counter clockwise.  This won't protect your SLA from going too low anymore but SLAs are cheap.  See how long it runs now.

One more thought on this, would I be at risk of damaging the V2 by doing this and then running low?

I doubt it would harm the V2, but it might not perform within it's specs at a lower voltage.

[drewloo]

Try running it w/ VR7 turned all the way counter clockwise.  This won't protect your SLA from going too low anymore but SLAs are cheap.  See how long it runs now.

One more thought on this, would I be at risk of damaging the V2 by doing this and then running low?

I wouldn't think so but that's probably a question for Mr. Grace. 

[Sloan Simpson]

Try running it w/ VR7 turned all the way counter clockwise.  This won't protect your SLA from going too low anymore but SLAs are cheap.  See how long it runs now.

One more thought on this, would I be at risk of damaging the V2 by doing this and then running low?

I wouldn't think so but that's probably a question for Mr. Grace. 

Yeah, good call 

We're about to open her up tonight, I think we're going for actually calibrating it. I'll report back.

[achalsey]

Yeah, good call 

We're about to open her up tonight, I think we're going for actually calibrating it. I'll report back.

Any possibility you could take some pictures if its not too late?  No reason really, but just curious what it looks like in there.

[F.O.Bean]

Inside a v2/v3 ia amazing. Every component just fits perfectly

[Sloan Simpson]

All we had was an iphone to shoot it with so not a detailed pic . . .



We did the calibration, then I tested it overnight and it shut down again    Will call Grace soon and get it shipped out I guess.

[F.O.Bean]

Bummer

[kirk97132]

Try running it w/ VR7 turned all the way counter clockwise.  This won't protect your SLA from going too low anymore but SLAs are cheap.  See how long it runs now.

Won't you need to do VR7 and VR8?

[drewloo]

Try running it w/ VR7 turned all the way counter clockwise.  This won't protect your SLA from going too low anymore but SLAs are cheap.  See how long it runs now.

Won't you need to do VR7 and VR8?

I could be wrong but I thought VR8 just sets the point where the low battery light starts to flash whereas VR7 controls the actual auto power-down circuit. 

[kirk97132]

Try running it w/ VR7 turned all the way counter clockwise.  This won't protect your SLA from going too low anymore but SLAs are cheap.  See how long it runs now.

Won't you need to do VR7 and VR8?

Oh right I had only looked at the diagram not actually read the instructions

I could be wrong but I thought VR8 just sets the point where the low battery light starts to flash whereas VR7 controls the actual auto power-down circuit.

[Sloan Simpson]

Just got it back. 11 days including shipping both ways and a weekend in there. New fuse, calibration, and update of the power supply circuit, $75+shipping. And they put on a new faceplate  The numbers have been worn off the old one for years. Now testing with the home stereo (and a Tekkeon, goodbye SLAs  , and will re-christen it at Crooked Fingers tonight.

[drewski1986]

Neil and the others at Grace Designs offer some of the best customer service around.  Good luck with your "new" V2.

[Sloan Simpson]

Turns out it's not fixed, it shut down again during Crooked Fingers tonight 

[Brian Skalinder]

Turns out it's not fixed, it shut down again during Crooked Fingers tonight 

Frustrating!  That really stinks.  A few thoughts...

I'd be very surprised if Grace didn't fix the unit, given their consistently outstanding customer care and quality service.  It certainly could happen, but I'd bet against it.

Do you know to what voltage Grace calibrated the low battery indicator and auto-shutoff?  The correct value depends on the battery to be used.  Did they know you planned to use the V2 with your Tekkeon, and your Tekkeon's voltage?

Did you, by chance, send Grace your power cable and battery along with the V2?  Or just the V2?  Wondering if they tested it with their or your cable / battery.  If they tested with their own, it might be time to re-visit your power cable.

Out of curiousity, from where do you get your power cables?  Were all the power cables in play during powering problems from the same source?  Earlier in the thread, you said the V2  worked fine with a borrowed power cable & battery...and it seems likely the borrowed cable was from a different source.  Maybe you have a bad source for cables?

FWIW, my money's still on the power cable.

[Sloan Simpson]

Turns out it's not fixed, it shut down again during Crooked Fingers tonight 

Frustrating!  That really stinks.  A few thoughts...

I'd be very surprised if Grace didn't fix the unit, given their consistently outstanding customer care and quality service.  It certainly could happen, but I'd bet against it.

Do you know to what voltage Grace calibrated the low battery indicator and auto-shutoff?  The correct value depends on the battery to be used.  Did they know you planned to use the V2 with your Tekkeon, and your Tekkeon's voltage?

Did you, by chance, send Grace your power cable and battery along with the V2?  Or just the V2?  Wondering if they tested it with their or your cable / battery.  If they tested with their own, it might be time to re-visit your power cable.

Out of curiousity, from where do you get your power cables?  Were all the power cables in play during powering problems from the same source?  Earlier in the thread, you said the V2  worked fine with a borrowed power cable & battery...and it seems likely the borrowed cable was from a different source.  Maybe you have a bad source for cables?

FWIW, my money's still on the power cable.

They said they set the low-battery to 5.5v and the auto-shutoff to 5v. I didn't send the cable or the battery to Grace. The problem happens with both my power cables, one of which was bought from Grace, the other one was made by a friend.

I've got a followup email out to Grace, we'll see what happens. It worked for 2.5 hours before shutting down tonight, but not sure how long Grace tested it; the problem may not have occurred for them.

[Brian Skalinder]

Any non-Grace hacks made to the Grace cable, like on the Tekkeon end?  Just trying to think of points of failure other than the V2 itself, since it just came back from service.

Short of spending the money to ship the entire set of gear back to Grace (V2, power cables, batteries), we need to isolate the point of failure in the chain -- something we've not quite done yet, if memory serves (though I haven't gone back and re-read the entire thread).

Do you have a way to test the Grace & other battery cable and batteries on a known-good V2?  And likewise test known-good battery cables and battery on the recently serviced V2?

[Sloan Simpson]

Any non-Grace hacks made to the Grace cable, like on the Tekkeon end?  Just trying to think of points of failure other than the V2 itself, since it just came back from service.

Short of spending the money to ship the entire set of gear back to Grace (V2, power cables, batteries), we need to isolate the point of failure in the chain -- something we've not quite done yet, if memory serves (though I haven't gone back and re-read the entire thread).

Do you have a way to test the Grace & other battery cable and batteries on a known-good V2?  And likewise test known-good battery cables and battery on the recently serviced V2?

The Grace cable isn't hacked; I bought it as a package with the Tekkeon from Grace, so it was ready to run when purchased.

Unfortunately I'm not able to do the tests you mention. There are only 3-4 tapers in town here, and mine is the only V2 (or Tekkeons).

[achalsey]

Unfortunately I'm not able to do the tests you mention. There are only 3-4 tapers in town here, and mine is the only V2 (or Tekkeons).

Not really much to add, but if you're ever up in Asheville for any reason we've got a good handful of V2s around (not sure about Tekkeons).

Thanks for the updates though, having got one myself recently will be interested to see how yours plays out.  Hoping for a quick fix!

[Brian Skalinder]

I'm baffled.  Sounds like the best option is to ship it all back to Grace -- V2, both battery cables, batteries -- and have them check it all, under conditions similar to the ones in which you're experiencing the failures.  Sucks!

[Sloan Simpson]

I'm baffled.  Sounds like the best option is to ship it all back to Grace -- V2, both battery cables, batteries -- and have them check it all, under conditions similar to the ones in which you're experiencing the failures.  Sucks!

The tech got back in touch today, we're going to do this.

[H₂O]

Is there any way problem with the mics or mic cables could cause this (i.e. excessive load on the V2)?

[F.O.Bean]

WTF? That sucks sloan

[Sloan Simpson]

Is there any way problem with the mics or mic cables could cause this (i.e. excessive load on the V2)?

FWIW, I've had the problem with two different pairs of mic cables. I don't even want to think about a mic problem! 

[Sloan Simpson]

The saga ends:

The good news is that
the V2 is perfectly fine. The bad news is that your batteries are
nearing the end of their life. The black Tekkeon is actually bulging, so
I would advise you to not use or charge that battery anymore and to
recycle it. The silver battery also has a very slight bulge and it
doesn't hold it's rated capacity, but it can most likely still be
useful.

[kirk97132]

The saga ends:

The good news is that
the V2 is perfectly fine. The bad news is that your batteries are
nearing the end of their life. The black Tekkeon is actually bulging, so
I would advise you to not use or charge that battery anymore and to
recycle it. The silver battery also has a very slight bulge and it
doesn't hold it's rated capacity, but it can most likely still be
useful.

I can fix those battereis for ya
http://taperssection.com/index.php?topic=153993.0

[Sloan Simpson]

The saga ends:

The good news is that
the V2 is perfectly fine. The bad news is that your batteries are
nearing the end of their life. The black Tekkeon is actually bulging, so
I would advise you to not use or charge that battery anymore and to
recycle it. The silver battery also has a very slight bulge and it
doesn't hold it's rated capacity, but it can most likely still be
useful.

I can fix those battereis for ya
http://taperssection.com/index.php?topic=153993.0

I ordered a new one already, but at some point in the future I may have you fix one of the old ones so I have a spare.

[Brian Skalinder]

Thanks for the update, SS.  Glad to hear it was just the batteries -- sure beats a major problem with the V2.  Best of luck with the new batteries, hope everything goes well!

[Sloan Simpson]

Tested at home yesterday, it ran for 12+ hours and the battery still wasn't dead 

[F.O.Bean]

Tested at home yesterday, it ran for 12+ hours and the battery still wasn't dead 

AWESOME! +T

[Sloan Simpson]

A friend sent me this link: http://www.tekkeon.com/recall/ . . . Looking back at when I bought the battery to when this problem started, it was probably only out of warranty for a couple weeks. It was purchased outside the date range they list, but I'd think Grace doesn't sell tons of Tekkeons, so maybe this was one of the recalled ones. Would be nice to have a brand new replacement for backup  I've submitted the serial to find out.

[flipp]

Check this thread http://taperssection.com/index.php?topic=107694.0 for specific serial numbers that were in the original recall notice as well as a few reports from others (including me) who have had various problems with some models of Tekkeons. Maybe your battery falls in the affected serial # ranges even if it doesn't fall within the specified date range.

[Sloan Simpson]

Turns out it's not a recall. Oh well.