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dave.king1
11-08-2018, 08:27 PM
My little Peavey PV6 mixed has let out some smoke, probably metric smoke despite the US origins of the name.

Anyway to cut to the chase U22 on the power board looks to have seen better days, unlike the rest of the components the writing can't be read indicating heat was produced there and the manual is of limited help.

The power supply delivers + 15V to one side and there is an inverter circuit to deliver -15V and this is where the frying took place.

U22 is listed in the cct diagram as being an NCP3063 which is fine but when checking online there are any number of suffix's after NCP3063 and the spec sheets indicate that they probably serve different functions so I'm not sure what I should drop my hard earned on.

Any advice gratefully received.

Should add I have a Behringer mixer as well but Ch1 has developed an dreadful amount of hum and of the 5 channels it is the only one with EQ & compression, the Peavey has EQ on all six channels which gives much better results hence the desire to get it sorted.

ps. Follow up to an earlier thread I finished getting a couple of Alpha pots from Jaycar for my mates pedal steel volume pedal @ $2.95 each, he has also purchased one from Canada along with a set of strings $124.00 landed ( ouch )

dave.king1
11-08-2018, 08:47 PM
Scratch that equivalent specs reveal that the MC34063A is the same thing and Jaycar stocks them for peanuts

WeirdBits
11-08-2018, 11:42 PM
As Simon would ask... roasted, salted or in the shell ;)

DrNomis_44
12-08-2018, 07:45 PM
From having a quick look at the datasheet for the MC34063A, it looks like that's doing all the regulation for the 15V supply rails, if it goes up in smoke again, you can buy an LM7815 (+15V 3-Terminal Regulator), and an LM7915 (-15V 3-Terminal Regulator) and use them to build a replacement +/- 15V power supply for the PV6 mixer, if you want I can draw up a circuit diagram for the replacement power supply and post it here.

dave.king1
13-08-2018, 06:11 AM
From having a quick look at the datasheet for the MC34063A, it looks like that's doing all the regulation for the 15V supply rails, if it goes up in smoke again, you can buy an LM7815 (+15V 3-Terminal Regulator), and an LM7915 (-15V 3-Terminal Regulator) and use them to build a replacement +/- 15V power supply for the PV6 mixer, if you want I can draw up a circuit diagram for the replacement power supply and post it here.

Thanks for the info and offer Doc, please do draw one up and post it.

The Jaycar equivalent is massive compared to the original item so building a new PS is probably the best option

DrNomis_44
13-08-2018, 09:47 AM
Thanks for the info and offer Doc, please do draw one up and post it.

The Jaycar equivalent is massive compared to the original item so building a new PS is probably the best option


No worries, here's a simple and easy to make +/- 15V Power Supply circuit, you should be able to buy everything you need from Jaycar Electronics, the circuit can be easily built on a piece of strip board, or pad per hole board, hope this sorts out the mixer, let me know how it goes:

27761

dave.king1
13-08-2018, 10:32 AM
Now that's decent service, thanks Doc

DrNomis_44
13-08-2018, 12:21 PM
Now that's decent service, thanks Doc


No worries at all mate, hope it gets the mixer going again.