Share your knowledge on these two classic MPCs
By SDC Tue Feb 19, 2013 1:43 am
The inverter suggested before arrived, but i would like to try MisterWhite suggestions before f*** with the original inverter.
Anyone know where is located T1 transformer?
By MisterWhite Tue Feb 19, 2013 3:33 am
Hey folks,

Here we go with some disgraceful gear pr0n of the inverter:

The inverter PCB as we know and love her:
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Unclothed:
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With the ring removed, dirty girl:
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Disturbing close-up of transformer and capacitor C1:
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Look at those holes:
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A threesome with S3000XL inverter (left) and S1100 model (center)
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So if your inverter is really noisy, it could help to wrap a few layers of electrical tape around the ring, as the ring can be loose.

If the noise is present in the audio, even very slightly, this indicates a problem with C1, which acts as a filter to stop the interference from the inverter making it back into the power supply. I have to say, it's very rare, so don't swap out C1 unless you hear that noise in your audio.

While the MPC60 inverters can be noisy, they do seem to be incredibly tough and it's mighty unusual for them to fail.

Some backlights can really help a lot with that noise, others don't, and I don't really understand why that is yet but I'm working on it.

Later folks!

Matt
By SDC Tue Feb 19, 2013 1:22 pm
Thank you so much for the lovely pics MisterWhite!!
Off to work! Will report back

Ps.: Just order one replacement backlight kit from your ebay store :)
Last edited by SDC on Tue Feb 19, 2013 7:22 pm, edited 1 time in total.
By SDC Tue Feb 19, 2013 2:35 pm
THE INVERTER NOISE ON MY 60II GONE FOR GOOD!!!!
(Thanks to MisterWhite)

The Process:

I've pulled out the inverter pcb and found it a bit rusty and with some "glue" residue

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So i went to my local electronics shop and bought a pcb cleaner. Here's the result:

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Next i pulled out the metal cover of the inverter, desoldering the 3 large points in the pcb. Here's what's behind the metal cover:

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This how the metal "ring" surrounding the main transformer looked like: (as you can see, there's only a small piece of tape on it)

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I applied a few layers of tape until the "ring" feels tight:

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Put it back to it's place:

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Ok, this wasn't solved my problem, but probably can be enough for many of you (like MisterWhite said)

So, i decided to change C1 capacitor. You can see it very well in this last picture. And BANG! NOISE GONE.
Total cost: 0.15$ :-D

Ps: I have no experience at all in electronics, but this is very easy to do by anyone.
By MisterWhite Wed Feb 20, 2013 12:28 am
Hey SDC,

Hehe, yes it helps if you reconnect the cables :)

But I'll go through a few backlights and select the quietest one I can find. It might help.

If you disconnect the backlight from the inverter, you will notice that the inverter gives out much more noise. Once the backlight is connected, you complete the circuit, and the backlight, in a small way, behaves like a capacitor, the inverter is usually much less noisy. It could be that the connection to your old backlight is faulty - it could be a bad backlight. These inverters do happen to be noisy though.

The MPC60ii will work normally with the inverter disconnected - the inverter only powers the backlight, it has no effect on the rest of the display.

Anyway, I will select a quiet backlight for you - let me know if it improves the noise for you.

If the noise really annoys you, there are other things that can be done - like fitting a different inverter board. I am working on some things.

Matt
Last edited by MisterWhite on Wed Feb 20, 2013 12:43 am, edited 1 time in total.
By MisterWhite Wed Feb 20, 2013 12:53 am
Hey SDC,

Your backlight seems to be totally worn out, it has probably been that way for years. This is very common. I guess the original backlight was never replaced in your MPC. But even if there is a faulty connection to the backlight, this new backlight will help - you just plug the new backlight's connecting cable into the inverter, it replaces the old connection and cable.

Be careful not to mix up the 2 connections to the inverter. Connect the backlight to P2. Connect the cable from the power supply to P1. Don't get those connections the wrong way round or you will blow a fuse...

Let me know about the noise with the new backlight, it could help :)

Matt
User avatar
By JUKE 179r Wed Feb 20, 2013 2:37 am
:lol:

I preferred Hollyoaks. :nod:
By MisterWhite Sun Feb 24, 2013 1:07 am
clint246clint wrote:This is better than Eastenders; what will happen next?


That's not saying much Clint. Removing your own appendix with a rusty fork is an improvement on Eastenders. I'm sure that this thread will have a happier ending.

SDC, I selected a very quiet backlight for you (posted Thurday 21-2-13), so I'm hopeful that it's going to help. All the backlights in this last batch were very quiet though, on my test inverters. I'm not certain why this is the case, yet.

Let me know how it works out!

Matt