220v to 110v conversion

[hemiguy2006]

Hi Techies, I have Power supply question.
Is there a difference in powering a radio from the built in power supply versus
using the 15 vdc input and using an external power supply????
Essentially isnt the built in power supply converting ac to dc and stepping down to 15 volts anyway????
Reason I ask is because I am getting a 220v box and was thinking about taking a 110v 15 VDC laptop power supply and hard
wiring it in place of the built in 220v power supply and mounting it inside the box. So you could use the removable power cord from the outside
as normal. So to clarify, I want to take the incoming feeds from the mains, bypass the 220 transformer, hard wire to the 110v input of the laptop
power supply , then take the low voltage output and splice that into the low voltage feeds that power the radio.
The radio in question consumes 40w
The power supply is input 100-230v ~ 2A 50/60 Hz output 15-24VDC 65W MAX.
Theoretically I think this should work Fine but maybe someone else can chime in with some more critical info.
Thanks in Advance

 

[Jboogie2384]

I had a radio I got from DOCS done. See if you could find an aka of the same radio then swap them. Much easier and the plugs are the same. The mini 777 I had done in the same manner and they play just fine. Foreign parts might give you an issue down the line or might not work at all. Possibly even burn out the radio. Good luck in any event.

 

[Superduper]

There might be a few challenges:

1) the dc-in jack is possibly switched. What position will you "fix" the switch if it's there?
2) what will happen if someone plugs in an external supply into that jack?
3) some digital switching supplies generate a lot of electrical noise which could affect the audio or AM radio.

 

[baddboybill]

I also used a transformer from Radio shack that was 110v AC in and 12v dc out and installed it in my sound master from Germany. I did how ever change it out with an AKA parts box I had gotten later with proper transformer from it, but it did work fine for time being

 

[Gluecifer]

I've wanted to do this to a few of my 110v boxes, as in the opposite of what Frank wants to do.

For some reason I thought it was more complicated than just 'power matching' one supply from one box to another one.
As in the supplies being from both 8D battery boxes.

I thought there'd be much more magic electrickery at work.


Be awesome if does work that way though!!




Rock On.

 

[Strānj-Bōōmbŏks]

"magic electrickery"

I'd like to hear Rick say this phrase in a video!!!

 

[hemiguy2006]

Ok, A parts box or aka would be a perfect solution, But parts may be hard to come by, As the radio was, very hard to come by.
WIth that said, if anyone has a parts box of any AKA of a

Let Me know.
I guess i also may have mis-conveyed what i want to do.
The laptop power supply in question, I have used before with a similar box and it powered the box just fine through the dc in jack.
With this new box im getting I want to leave the dc input alone.
I want to hardwire the laptop power supply in place of the existing 220 supply.
So Essentially it will work as normal.
You can plug the 110v mains removable power plug from the radio to the wall.
So, if the battery box bypass switch, (whether it be an AC/DC switch, or built into the receptacle in the back of the radio)
will still work as intended.
So my question is,
On any given box or A (J-747s Specifically) Does the 15v DC input, supply the same current as the low voltage side of the supply on the built in power supply???

 

[baddboybill]

Ok, A parts box or aka would be a perfect solution, But parts may be hard to come by, As the radio was, very hard to come by.
WIth that said, if anyone has a parts box of any AKA of a
[ Image ]
Let Me know.
I guess i also may have mis-conveyed what i want to do.
The laptop power supply in question, I have used before with a similar box and it powered the box just fine through the dc in jack.
With this new box im getting I want to leave the dc input alone.
I want to hardwire the laptop power supply in place of the existing 220 supply.
So Essentially it will work as normal.
You can plug the 110v mains removable power plug from the radio to the wall.
So, if the battery box bypass switch, (whether it be an AC/DC switch, or built into the receptacle in the back of the radio)
will still work as intended.
So my question is,
On any given box or A (J-747s Specifically) Does the 15v DC input, supply the same current as the low voltage side of the supply on the built in power supply???

It's usually a little more volts that come off the output of transformer. In other words it's not going to be exactly 15v. I think the biggest thing you have to worry about is the boombox uses 40 watts to power up and if transformer does not put out at least that much the transformer could burn out but another idea is buying a step up transformer on eBay. I got one for $4 shipped to step up to the 220v needed and it's a small transformer that plugs into wall it is recommended up to 50 watts...

 

[baddboybill]

I have this transformer out of a parts unit that is 110v to 15v... The box is rated at 30 watts input

 

[gsbadbmr]

. I still have my Elta from BP that is 220V...i'm too scared to power it up any other way except with Duracell batteries. I hope you figure something out

 

[hemiguy2006]

Bill what kind of box is that out of ?

 

[hemiguy2006]

The last radio I powered with this laptop power supply was the Elta Master blaster.
It did a great job.

 

[Reli]

but another idea is buying a step up transformer on eBay. I got one for $4 shipped to step up to the 220v needed and it's a small transformer that plugs into wall it is recommended up to 50 watts...

Ditto, that's what I do

 

[baddboybill]

Bill what kind of box is that out of ?

Its out of my Tisonic PR9000 parts unit AKA of my Kingspoint I just traded to Jr.

 

[kittmaster]

It would make more sense to replace the transformer that can step down the 110 to 15V.

That is what I did with my J1, I'm sure many around here have a few transformers from junk boxes hanging around.

Just have to find something with a similar profile and wire it in.

That is how I'd do it.

 

[Ken]

 

[hemiguy2006]

I found something really nice!!!!!http://cgi.ebay.com/ws/eBayISAPI.dl...ssPageName=VIP:watchlink:top:en#ht_4390wt_907

 

[Superduper]

Frank.... that is a switching power supply. The exact same kind found in the laptop supplies, computers, etc. The only rail you would be interested in is the +15v rail. The 5.1v rail is wasted since that is used primarily for digital circuits. The -15v circuit is completely useless. It's purpose is to provide a dual +/- 15v suply which has the potential for creating more powerful amps (+/- 15v = 30v potential). but the problem is that it's unequal with only 350mA capability and your boombox is not built to realize the benefits of a dual supply and impractical for battery powered designs which uses only the positive rail.

So what's left is a +15v regulated supply @ 2amps. Or 30watts. There could be other factors such as efficiency differences but probably not worth discussing here.

But like another member stated -- it's simply best and easiest to just replace the transformer with a new linear transfo.

THIS one here will be an easy swap for you, is suitably sized, and will work fine if it fits:
[ebay]320797631742[/ebay] $20.40 shipped.

Or.... if you are seriously looking to do a transformer swap, I can send you a brand new 30watt one for $14 shipped. I still have a handful in stock. I've used those to replace defective transformers or retrofitted (240-120v) conversions in numerous boxes and all work fine.

 

[docs]

Frank.... that is a switching power supply. The exact same kind found in the laptop supplies, computers, etc. The only rail you would be interested in is the +15v rail. The 5.1v rail is wasted since that is used primarily for digital circuits. The -15v circuit is completely useless. It's purpose is to provide a dual +/- 15v suply which has the potential for creating more powerful amps (+/- 15v = 30v potential). but the problem is that it's unequal with only 350mA capability and your boombox is not built to realize the benefits of a dual supply and impractical for battery powered designs which uses only the positive rail.

So what's left is a +15v regulated supply @ 2amps. Or 30watts. There could be other factors such as efficiency differences but probably not worth discussing here.

But like another member stated -- it's simply best and easiest to just replace the transformer with a new linear transfo.

THIS one here will be an easy swap for you, is suitably sized, and will work fine if it fits:
[ebay]320797631742[/ebay] $20.40 shipped.

Or.... if you are seriously looking to do a transformer swap, I can send you a brand new 30watt one for $14 shipped. I still have a handful in stock. I've used those to replace defective transformers or retrofitted (240-120v) conversions in numerous boxes and all work fine.

Norm your a bloody legend and no mistake.

 

[k2j]

Makes sense to me.

How do you guys label the modified boombox so no-one tries to plug it into 220 like stated on box?