PODZUMA BATTERY

[jtlanders]

I'm going to attempt to build a modifed version of Darren Kuzma's Podzuma featured in the current sales flyer, but I have a couple ?s first. If there is a link I could e-mail him directly let me know (if he would not mind of course).

1. I know what the blue LED is for, but the parts list also includes a red LED (070-065). Is this a "charging" light or what? He does not mention it in the article, and it does not appear in the schematics. Where is it wired in?

2. He suggests using the 12V 5Ah battery (140-460). Would there be a problem using the 12V 7.2Ah (140-465)? I'm looking for even longer run times at high volume.
Could I use the same 800mA DC adapter (129-330) to charge it, or would an adaptor with a larger mA capacity be better? If so which one?

3. What is the resistor in line with the LED in the battery/charging schematic?

Thanks for the responses. You guys rock!

[bill]

> I'm going to attempt to build a modifed
> version of Darren Kuzma's Podzuma featured
> in the current sales flyer, but I have a
> couple ?s first. If there is a link I could
> e-mail him directly let me know (if he would
> not mind of course).

<A HREF="mailto:darrenk@parts-express.com">darrenk@parts-express.com</A>

> 1. I know what the blue LED is for, but the
> parts list also includes a red LED
> (070-065). Is this a "charging"
> light or what? He does not mention it in the
> article, and it does not appear in the
> schematics. Where is it wired in?

It does appear in the schematic; it's the 12 volt automotive LED with the series resistor. It lights when power is applied to the external DC input.

The blue LED is the one not shown on the schematic; it replaces the LED pilot light from the T-amp.

> 2. He suggests using the 12V 5Ah battery
> (140-460). Would there be a problem using
> the 12V 7.2Ah (140-465)? I'm looking for
> even longer run times at high volume.
> Could I use the same 800mA DC adapter
> (129-330) to charge it, or would an adaptor
> with a larger mA capacity be better? If so
> which one?

The bigger battery won't fit the enclosure as designed. Look at the dimensions.

> 3. What is the resistor in line with the LED
> in the battery/charging schematic?

As I said, it's part of the 12 volt red LED assembly.

> Thanks for the responses. You guys rock!

HTH,
Bill

[jtlanders]

> <A HREF="mailto:darrenk@parts-express.com">darrenk@parts-express.com</A> It does appear
> in the schematic; it's the 12 volt
> automotive LED with the series resistor. It
> lights when power is applied to the external
> DC input.

> The blue LED is the one not shown on the
> schematic; it replaces the LED pilot light
> from the T-amp.

> The bigger battery won't fit the enclosure
> as designed. Look at the dimensions.

> As I said, it's part of the 12 volt red LED
> assembly.

> HTH,
> Bill

That's what I thought about the resistor with the LED, just wanted to double check.

I'm going to re-design the dimensions to make the new battery fit. So, can I use that same DC adaptor (12V 800mA) to charge the larger battery?

[curt_c]

> I'm going to re-design the dimensions to
> make the new battery fit. So, can I use that
> same DC adaptor (12V 800mA) to charge the
> larger battery?

Sure, it will work fine. It will just just take longer to recharge the larger battery.

C

[envisionelec]

> I'm going to attempt to build a modifed
> version of Darren Kuzma's Podzuma featured
> in the current sales flyer, but I have a
> couple ?s first. If there is a link I could
> e-mail him directly let me know (if he would
> not mind of course).

> 1. I know what the blue LED is for, but the
> parts list also includes a red LED
> (070-065). Is this a "charging"
> light or what? He does not mention it in the
> article, and it does not appear in the
> schematics. Where is it wired in?

> 2. He suggests using the 12V 5Ah battery
> (140-460). Would there be a problem using
> the 12V 7.2Ah (140-465)? I'm looking for
> even longer run times at high volume.
> Could I use the same 800mA DC adapter
> (129-330) to charge it, or would an adaptor
> with a larger mA capacity be better? If so
> which one?

> 3. What is the resistor in line with the LED
> in the battery/charging schematic?

> Thanks for the responses. You guys rock!

You can also use an external battery, if you want. A car battery would last for a very long time...

[thespeakerguy]

Aren't hurt by a slow charge rate.

Do keep the unit fully charged whenever possible.

Charge the unit after each use

Avoid deep discharging the battery.

When fully charged the battery should be kept at about 14.4V max. (25degC)

[jtlanders]

> Sure, it will work fine. It will just just
> take longer to recharge the larger battery.

> C

Forgive my ignorance, but would a 13.5V 1700 DC adaptor like this one charge the larger battery (140-465) faster and also not harm it if left hooked up over time like a house alarm battery?

<A HREF="http://www.partsexpress.com/pe/showd...umber=120-1135">http://www.partsexpress.com/pe/showd...umber=120-1135</A>

This is one of the DC adapters the PE site recommends for the T amp.

Thanks again.

JL

[jtlanders]

> Aren't hurt by a slow charge rate.

> Do keep the unit fully charged whenever
> possible.

> Charge the unit after each use

> Avoid deep discharging the battery.

> When fully charged the battery should be
> kept at about 14.4V max. (25degC)

Thanks for the tips. So deep discharging will not allow a full charge after that, or what? Maybe sealed lead-acids are different, but I've always heard it's good for most all rechargable batteries to fully discharge once in a while to avoid memory effects.

[thespeakerguy]

> Thanks for the tips. So deep discharging
> will not allow a full charge after that, or
> what? Maybe sealed lead-acids are different,
> but I've always heard it's good for most all
> rechargable batteries to fully discharge
> once in a while to avoid memory effects.

Lead acid are the exception. It takes special cells for golf carts, called deep discharge type. Heavier, less efficient, and more $$$

[darrenk]

Hi,

I think most of the guys hit this stuff already, but thought I'd chime in to help clarify if needed.

1. The Blue LED replaces the stock red LED that shows the T-amp is on. The red automotive LED is basically a charging indicator, and can be seen in the schematic below. So, when you plug in the wall wart, the red light comes on.

2. You can use a bigger battery, no problem. I wouldn't bother using a different adaptor, as they mentioned it will just take a little longer to charge. But, it depends on what you are doing with the unit. If you plan on using it very frequently and running the battery down a lot, you may want to consider using a 12V battery charger like you would buy at Sears or Walmart.

3. I guess that's answered in question 1. The 12V automotive LED comes with a current limiting resistor built into its package already, so you don't need an external one. Just hook it up and go!

See ya,

Darren

> I'm going to attempt to build a modifed
> version of Darren Kuzma's Podzuma featured
> in the current sales flyer, but I have a
> couple ?s first. If there is a link I could
> e-mail him directly let me know (if he would
> not mind of course).

> 1. I know what the blue LED is for, but the
> parts list also includes a red LED
> (070-065). Is this a "charging"
> light or what? He does not mention it in the
> article, and it does not appear in the
> schematics. Where is it wired in?

> 2. He suggests using the 12V 5Ah battery
> (140-460). Would there be a problem using
> the 12V 7.2Ah (140-465)? I'm looking for
> even longer run times at high volume.
> Could I use the same 800mA DC adapter
> (129-330) to charge it, or would an adaptor
> with a larger mA capacity be better? If so
> which one?

> 3. What is the resistor in line with the LED
> in the battery/charging schematic?

> Thanks for the responses. You guys rock!

[wg_ski]

> Thanks for the tips. So deep discharging
> will not allow a full charge after that, or
> what? Maybe sealed lead-acids are different,
> but I've always heard it's good for most all
> rechargable batteries to fully discharge
> once in a while to avoid memory effects.

If you deeply discharge a lead-acid, it will develop a high internal resistance and will have a hard time accepting a charge. When you put 14.4V on it, it just won't draw anything. And the longer you let sit in the discharged state, the worse it gets. To "fix" it, you need to overvoltage it (to say, 30V) until it starts outgassing and drawing current again. But since you boil off electrolyte doing that, you lose capacity every time. And you can only do it so many times before the battery is toast.

[Dirk]

Provided Link: Battery University :-)


> Lead acid are the exception. It takes
> special cells for golf carts, called deep
> discharge type. Heavier, less efficient, and
> more $$$

...and if you fully drain a lithium battery, it might not ever want to take a charge again. :-D

[jtlanders]

Thanks to everyone for the information. I already have a 800 mA adaptor so I'll just go with that. I'll only be using it on weekends anyway.

One last thing. I'm guessing I'll notice a decrease in volume when the battery is close to being fully discharged and that is when it will need to be turned off and recharged to avoid damage? Is that right?

Thanks again.

JL

[curt_c]

> One last thing. I'm guessing I'll notice a
> decrease in volume when the battery is close
> to being fully discharged and that is when
> it will need to be turned off and recharged
> to avoid damage? Is that right?

Right.

Sealed lead/acids will polarize if run down and are essentially trash.

The other option not mentioned is to make an adapter to plug into your car cigarette lighter or accessory jack. Now you can charge/run off of the vehicle battery/charging system as well. -I'd probably fuse it at around 3-5 amps, just in case...

C

[darrenk]

Hi JL,

From my experience using and testing the Podzuma, when the battery starts to run out of juice the T-amp will start to distort, particularly on bass notes. It's kind of a clicking crackly sort of sound that may not at first sound like it is the amp. If it starts to sound "not right" then it's time to stop.

As far as I can tell I was able to fully recover the battery once it got to this stage with only the trickle charge.

See ya,

Darren

> Thanks to everyone for the information. I
> already have a 800 mA adaptor so I'll just
> go with that. I'll only be using it on
> weekends anyway.

> One last thing. I'm guessing I'll notice a
> decrease in volume when the battery is close
> to being fully discharged and that is when
> it will need to be turned off and recharged
> to avoid damage? Is that right?

> Thanks again.

> JL