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MistyBuff

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#247829 25-Feb-2019 13:21
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Hello,

 

 

 

Looking for some pro-tips on where I can find a 16v AC 1 Amp power adapter for a mixing desk I recently acquired.

 

 

 

It's a Peavey PV8 mixing console, bought off TM without a power supply. I thought it would be easy to find a replacement but I'm really struggling to find something that will meet its power demands. Any advice? Links very welcome!

 

 

 

Thanks,

 

 

 

Jack

 

 

 


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timmmay
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  #2186914 25-Feb-2019 13:34
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I typed the model into Google and found this power supply on ebay. Shipping's a bit expensive. There's also this, and this. Jarcar has a suitable power supply, but you'd have to solder the right plug onto it.




sbiddle
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  #2186916 25-Feb-2019 13:35
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Quick search shows Atlas Gentech stock one https://atlasgentech.co.nz/16vac-1-amp-plug-pack.html but you'd need to find a reseller to buy one from.

 

Jaycar sell one but it's not regulated which may or may not be an issue https://www.jaycar.co.nz/16v-ac-1-25-amp-alarm-power-supply/p/MP3021

 

 


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  #2186920 25-Feb-2019 13:48
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If you're in CHCH you could try Ecotech

 

Or Ecocentrals Eco-shop.

 

Or your local E-waste recycling store.

 

 

 

You could also easily use a re-purposed 16V laptop power adaptor, you'd just need to find a universal one that can change V to match your requirements.




MistyBuff

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  #2186926 25-Feb-2019 13:59
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Hi Timmmay, thanks for those links - I see they all need US input voltage, so would I need a step-down transformer to use them here?!


tehgerbil
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  #2186933 25-Feb-2019 14:16
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MistyBuff:

 

Hi Timmmay, thanks for those links - I see they all need US input voltage, so would I need a step-down transformer to use them here?!

 

 

Hovering over the photos - It appears to say "I/P:AC100" - aka: input 100v AC and there doesn't appear to be a physical switch to rewire the fuse to accept 230V, so yes I would very much say you'd need a step down transformer.


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  #2186934 25-Feb-2019 14:19
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MistyBuff:

 

Hi Timmmay, thanks for those links - I see they all need US input voltage, so would I need a step-down transformer to use them here?!

 

 

Most plug packs these days are multi voltage for the input so will work on 100V - 240V and the ones in that eBay listing are like this. You can choose an adapter plug in the auction for Australia, but remember that using an adapter plug for a permanently connected device is technically illegal, and if you are using this in an environment where electrical tagging is required then you may not find somebody who will tag it with an adapter.

 

 


 
 
 
 

Shop now for Dyson appliances (affiliate link).

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  #2187535 26-Feb-2019 13:26
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Depends on what exactly you need, worst-case get a 16V transformer and feed it the output of that. However that's totally unregulated, so it may not be what the mixer needs.

 

 

I'm guessing it takes AC input because it uses a filtered linear regulator internally to avoid switchmode noise from the typical external brick? Can't see why else you'd want AC input.

 

 

Another option is to open it up, find out what the 16VAC gets converted to, and splice in external DC connection at that point. So bypass the internal power supply and feed in the power directly from an external source. You'd just need to make sure it's well-filtered it it's coming from a SMPS.

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  #2187538 26-Feb-2019 13:28
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sbiddle:

Most plug packs these days are multi voltage for the input so will work on 100V - 240V and the ones in that eBay listing are like this.

 

 

Those are going to be switchmode supplies and therefore noisy. See my previous post, the odd power arrangements could be to deal with the noise issues that standard SMPS would cause.

frankv
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  #2187616 26-Feb-2019 15:18
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The first question is whether you really need a 16VAC supply... my guess is that it gets rectified to 5VDC internally, possibly by a device which is good for 9-36V. I'd check with the manufacturer to see if a 12VAC or 24VAC would do. 24VAC is very common for Xmas lights.

 

Or just try it with 12VAC... lower voltage isn't going to do any harm.

 

You're welcome to come and rummage around in my drawer full of spare power supplies... I know I have an 18V supply there somewhere, and may very well have a 16V one.

 

 


SepticSceptic
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  #2187672 26-Feb-2019 16:55
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Being an ausio device, the AC is could be split into positive and negative 12v rails, maybe for op-amps, etc.

 

As per above, AC so no noisy switch-mode noise. I've done that myself using AC transformers, rather than switchmodes. Can be a bit of a bother trying to remove swutchmode hash noise ( and oscillation ,etc), without careful design.


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  #2187717 26-Feb-2019 19:02
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sbiddle:

 

Quick search shows Atlas Gentech stock one https://atlasgentech.co.nz/16vac-1-amp-plug-pack.html but you'd need to find a reseller to buy one from.

 

Jaycar sell one but it's not regulated which may or may not be an issue https://www.jaycar.co.nz/16v-ac-1-25-amp-alarm-power-supply/p/MP3021

 

 

 

 

AC plugpacks are not regulated, they are just a bare transformer in a box with pins on it. Really nice way to send all sorts of nasty mains noise into a product who will have their support staff then try to sell you a power conditioner to clean up what any competant DC outputting plugpack would filter anyway.





Richard rich.ms

 
 
 

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richms
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  #2187718 26-Feb-2019 19:05
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neb:
sbiddle:

 

Most plug packs these days are multi voltage for the input so will work on 100V - 240V and the ones in that eBay listing are like this.

 

Those are going to be switchmode supplies and therefore noisy. See my previous post, the odd power arrangements could be to deal with the noise issues that standard SMPS would cause.

 

Transformer supplies are noiser since they just pass all the crap from other switchmode supplies primary side into the product. Active power factor correction gear can make a tonne of crap on the power when its under load. Also laptop bricks are terrible at it. With an AC transformer that just gets stepped down and then straight inside the shielded case of the device. I had a cheap 2 input XLR mic mixer that needed an AC power supply to make its phantom power work and it was just useless unless I plugged it in via an isolating transformer, even then still had some noise come in.





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  #2187733 26-Feb-2019 20:19
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Hi, we're an Atlas Gentech reseller, we can supply one for $38 plus GST and shipping. https://www.fusionautomation.co.nz/product/16vac-1-amp-plug-pack/

neb

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  #2188740 28-Feb-2019 11:56
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richms:

Transformer supplies are noiser since they just pass all the crap from other switchmode supplies primary side into the product. Active power factor correction gear can make a tonne of crap on the power when its under load. Also laptop bricks are terrible at it. With an AC transformer that just gets stepped down and then straight inside the shielded case of the device. I had a cheap 2 input XLR mic mixer that needed an AC power supply to make its phantom power work and it was just useless unless I plugged it in via an isolating transformer, even then still had some noise come in.

 

 

Ah, yeah, pure AC rather than a linear DC supply is going to be a problem. With low-noise I actually meant a transformer-based linear DC supply, typical linear regulators have a ripple rejection factor of 60-80dB, falling off at higher frequencies but still pretty high in the 100kHz region of higher-frequency SMPS'. I've got a linear USB supply that I use for some sensitive measuring equipment that for some stupid reason they decided to power off USB power, typically the worst kind of crap power you can get from cheap Chinese USB bricks, and it's specifically designed to be as low-noise as possible for applications like this.

 

 

For pure AC, you'd probably want a sinewave tracking filter and/or multi-stage EMI filter before the transformer. I've got a DIN-rail mount sinewave tracking filter that I might be persuaded to part with, although it's a bit pricey...

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  #2188744 28-Feb-2019 12:01
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For the really geeky, an interesting application note on using an LDO linear regulator to deal with noise on the output of a standard SMPS.

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