VU BUFFER & PEAK LED KIT BUILD THREAD

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hyped
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Re: VU BUFFER & PEAK LED KIT BUILD THREAD

Post by hyped »

Hi Guys,
I just got a VU Buffer and peak led kit to use with a SIFAM AL29W which should land shortly! I have never wired up a VU before so I apologise if its a stupid question. In relation to taking a audio signal into the VU meter via the board do I just split the audio output coming from the output of amps PCB? Split it with some kind of butt/Y splitter?

Any feedback would be appreciated! Thanks Guys

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Re: VU BUFFER & PEAK LED KIT BUILD THREAD

Post by Joe Malone »

hyped wrote:Hi Guys,
I just got a VU Buffer and peak led kit to use with a SIFAM AL29W which should land shortly! I have never wired up a VU before so I apologise if its a stupid question. In relation to taking a audio signal into the VU meter via the board do I just split the audio output coming from the output of amps PCB? Split it with some kind of butt/Y splitter?

Any feedback would be appreciated! Thanks Guys
Yes you can split the signal at the input to the amp or the output of the amp and send it to the vu buffer in and wire the VU meter to the VU buffer meter output. The VU buffer will need 12v to 36v power rail to run on.
Joe :-)
JLM Audio
Capturing Audio without Injury

hyped
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Joined: Fri Nov 04, 2016 11:31 pm

Re: VU BUFFER & PEAK LED KIT BUILD THREAD

Post by hyped »

Hi Joe,
Thanks for reply appreciated mate. What is the rough current draw of a buffer board overall? Im thinking of splitting 1x12VAC (via bridged rectifier) secondary rated at0.8A between both boards would that suffice?

Cheers mate

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Re: VU BUFFER & PEAK LED KIT BUILD THREAD

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hyped wrote:Hi Joe,
Thanks for reply appreciated mate. What is the rough current draw of a buffer board overall? Im thinking of splitting 1x12VAC (via bridged rectifier) secondary rated at0.8A between both boards would that suffice?

Cheers mate
The VU Buffer kit only use about 30mA each. It is the bulbs or leds that light the meters that will use the most current. Best to regulate the power rail if it is a low voltage. Or if using a high voltage rail from a power amp only a series drop resistor is needed to drop the voltage down to a use able level.
Joe :-)
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hyped
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Joined: Fri Nov 04, 2016 11:31 pm

Re: VU BUFFER & PEAK LED KIT BUILD THREAD

Post by hyped »

Hey Joe,

Thanks very much for your reply mate. Ok, so my Sifam AL29W arrived today http://www.sifammeters.com/Audio_Level/ALPresentor.htm

This is going to show my stupidness but I'm not sure how I connect it to the buffer board???

There is two faston terminals on the VU meter. One marked + and other looks like S, assuming that is signal? I can't correlate to how I connect it to the board??

I was expecting to see two for power and two for signal. Sorry for the stupid question joe would appreciate confirmation if you could be so kind mate.

Thanks heaps mate

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Re: VU BUFFER & PEAK LED KIT BUILD THREAD

Post by Joe Malone »

hyped wrote:Hey Joe,

Thanks very much for your reply mate. Ok, so my Sifam AL29W arrived today http://www.sifammeters.com/Audio_Level/ALPresentor.htm

This is going to show my stupidness but I'm not sure how I connect it to the buffer board???

There is two faston terminals on the VU meter. One marked + and other looks like S, assuming that is signal? I can't correlate to how I connect it to the board??

I was expecting to see two for power and two for signal. Sorry for the stupid question joe would appreciate confirmation if you could be so kind mate.

Thanks heaps mate
Real Sifam meters only have 2 terminals on the meter for audio in. You can connect the VU Buffer with disabled rectifier mod done directly to these you terminals either way around doesn't matter. All lamps are rear mounted separate optional parts either clip on or lightbox which have there own 2 terminals which just wire across the 12v power rails.

Make sure you disabling the rectifier for meter with internal rectifiers as shown at the beginning of this thread.
Image
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hyped
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Joined: Fri Nov 04, 2016 11:31 pm

Re: VU BUFFER & PEAK LED KIT BUILD THREAD

Post by hyped »

Hey Joe

Thanks for your reply appreciated mate! Ok, so if I'm reading
It correctly. The two faston are for signal only, not for power? E.g. No power source needs to go to VU itself

So I would have 12-36ish vdc into the buffer board. Audio Output of buffer board into the two faston tabs on back on VU and a separate ac 12VAC tap going to the overhead bulbs (providing they are 12v bulbs) is that correct?

Cheers mate sorry for all the Qs

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Re: VU BUFFER & PEAK LED KIT BUILD THREAD

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hyped wrote:Hey Joe

Thanks for your reply appreciated mate! Ok, so if I'm reading
It correctly. The two faston are for signal only, not for power? E.g. No power source needs to go to VU itself

So I would have 12-36ish vdc into the buffer board. Audio Output of buffer board into the two faston tabs on back on VU and a separate ac 12VAC tap going to the overhead bulbs (providing they are 12v bulbs) is that correct?

Cheers mate sorry for all the Qs
Yes correct. But you can use the same 12vdc to run the 12v lamps or if 24vdc to run 2 x 12v lamps in series. No need for any ac rail.
Joe :-)
JLM Audio
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hyped
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Re: VU BUFFER & PEAK LED KIT BUILD THREAD

Post by hyped »

Hey Joe,
Wondering if you could give me some pointers. I've completed one of the buffer boards and connected it to approx 17vdc via two batteries to sifam vu I have omitted the two diodes and one resistor as per instructions. I've got a test tone that is measuring around 1.3v issue is when connected it doesn't seem I'm getting any signal or very little signal not enough to move the vu meters. I've tried moving the trim pots but still don't seem to be getting signal to the vu

I've tried the vu separately and it works fine going just over the 0db point with 1.3v applied. Any ideas?

I'm pretty "sure" it's put together maybe not!???
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Re: VU BUFFER & PEAK LED KIT BUILD THREAD

Post by Joe Malone »

hyped wrote:Hey Joe,
Wondering if you could give me some pointers. I've completed one of the buffer boards and connected it to approx 17vdc via two batteries to sifam vu I have omitted the two diodes and one resistor as per instructions. I've got a test tone that is measuring around 1.3v issue is when connected it doesn't seem I'm getting any signal or very little signal not enough to move the vu meters. I've tried moving the trim pots but still don't seem to be getting signal to the vu

I've tried the vu separately and it works fine going just over the 0db point with 1.3v applied. Any ideas?

I'm pretty "sure" it's put together maybe not!???
You have not fitted D1 so the VU buffer will never power up. D1 stops damage from power reverse polarity. You need to fit it or a wire link in D1 to make it work.
Joe :-)
JLM Audio
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hyped
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Re: VU BUFFER & PEAK LED KIT BUILD THREAD

Post by hyped »

Hey Joe,

Oops!!! :/ sorry I was focused on not having the diodes as it's
Rectified VU!

Ok so I have

Jumper on D2
Nothing on D3

Do I need a diode on both D1 and D4 or just D1 sorry for that!

hyped
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Re: VU BUFFER & PEAK LED KIT BUILD THREAD

Post by hyped »

Ok well diode on d1 and d4 , d2 jumper. D3 ommited and3k3 resistor above d2 ommited also.

Still no joy :( appears to be no signal at output

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Re: VU BUFFER & PEAK LED KIT BUILD THREAD

Post by Joe Malone »

hyped wrote:Ok well diode on d1 and d4 , d2 jumper. D3 ommited and3k3 resistor above d2 ommited also.

Still no joy :( appears to be no signal at output
Let me know the voltages at all 8 pins of the opamp measured to 0v?
Joe :-)
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hyped
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Re: VU BUFFER & PEAK LED KIT BUILD THREAD

Post by hyped »

Hey Joe
Thanks mate, here are the measurements pin to gnd
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Joe Malone
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Re: VU BUFFER & PEAK LED KIT BUILD THREAD

Post by Joe Malone »

hyped wrote:Hey Joe
Thanks mate, here are the measurements pin to gnd
Ok that proves the opamp and circuit are working correctly. The only thing is that the 100R and 5k trimpot may be open circuit or the input or output circuit has a solder short. Attach here a large in focus well lit top and bottom photo of the pcb so I can see all parts clearly and all soldering clearly. if there is lots of flux under the pcb clean it first with some alcohol like isocol and a old toothbrush.
Joe :-)
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