PSU for V2 info pls

[pingu]

Hi
Has anyone got any ideas about a PSU for the V2 please?
I need a cheapo working AC 12v PSU just to test a V2 for the present so don't want to spend on commercial job in case the V2 is no good
My thoughts were a simple surge/filter on the 240v input (couple of x/y caps and a vdr) then a 12v 15va toroidal transformer, which I have in the spares box.
Will this do or will I need some stability circuit on the 12 volt output?

Any help greatly appreciated

Martin

[PinkFloyd]

Hi Martin,

12V / 15VA is fine.... class X2 across the line (L/N) and class Y between Earth and live and Earth and neutral is perfect, that's all you need. 2.1mm DC plug is the correct size.

Mike.

[PinkFloyd]

I've got hundreds of VDR's perfect for the job so if you want one I'll pop it in the post, I also have the X2 and Y caps if you need them.

[pingu]

Sept 8, 2017 12:33:04 GMT PinkFloyd said:

I've got hundreds of VDR's perfect for the job so if you want one I'll pop it in the post, I also have the X2 and Y caps if you need them.

Thanks for the kind offer Mike.
I have a couple of caps/vdrs made up so I'll use one of those, left over from anothe project.
Is the connection for the psu centre posative?
I'll sort out the psu and have a look inside the V2 over the weekend. Then I'll pick your brains about the condition of the insides and sort out the upgrade bits
Regards
Martin

[PinkFloyd]

It's not a DC power supply so there is no polarity at the plug Martin but hook the red wire on the secondary to the centre pin anyway.

[pingu]

Sept 8, 2017 19:06:18 GMT PinkFloyd said:

It's not a DC power supply so there is no polarity at the plug Martin but hook the red wire on the secondary to the centre pin anyway.

Hi Mike,
Doh stupid school boy error lol
Let you know how it's all looking over the weekend after I've recovered from work tonight 

Cheers
Martin

[pingu]

Sept 8, 2017 19:06:18 GMT PinkFloyd said:

It's not a DC power supply so there is no polarity at the plug Martin but hook the red wire on the secondary to the centre pin anyway.

Hi Mike,
So opened up the V2 some minor discolouration around vale hole in top boead and around TR1/2 and R 1 - 4 but only very slight and Btm of print is ok.
On Btm board much more scorching on base of TR 207/206 and TR 208 R 218/215, D203/204 but again all underside ok no scorching or print lifting
The valves are 6922s one is a Philips the other may be but blue printing has worn off.

I'll fire it up later and see what's working

Regards
Martin

Ps. was going to add some pix but can't seem you get them off the IPad but I can mail the to you if you wish.
M

[pingu]

Hi Mike,

Well despite scorch marks trannies resists and zeners all seems to work very well. Looks like a couple ot the parts have been replaced. A bit of hum when no signal is present but not worth mentioning and only at full volume, maybe because it's not in the case.

I'll mail you to get the caps and other bits.

Any thoughts on heat damage appreciated.

All the best
Martin

[pingu]

Sept 8, 2017 12:30:13 GMT PinkFloyd said:

Hi Martin,

12V / 15VA is fine.... class X2 across the line (L/N) and class Y between Earth and live and Earth and neutral is perfect, that's all you need. 2.1mm DC plug is the correct size.

Mike.

Hi Mike, All,
Just a quick update, observation.
I used a 12 volt 50va tranys for a while on the V2. It seemed to give a bigger bolder sound but the amp ran hotter than with the 30va one.
Not sure whether to keep the 30va and sacrifice a little of the amps performance or go the hotter running

Then again this may all be a figment of my imagination, just knowing I'm using a diffrent trany.
Any thoughts anyone

All the beat
Martin

[PinkFloyd]

The current doesn't matter, the amp will only draw what it needs from the current pool BUT the VD under load does matter

What voltage AC are you getting when you measure the 50VA toroid's AC output under no load Martin?

[pingu]

Oct 19, 2017 20:50:35 GMT PinkFloyd said:

The current doesn't matter, the amp will only draw what it needs from the current pool BUT the VD under load does matter

What voltage AC are you getting when you measure the 50VA toroid's AC output under no load Martin?

Hi Mike

The 50va is giving 13.9v with no load and the 30va is giving 14.4v with no load. The only diffrence is as the 50va was jury rigged it was running straight from mains and the 30va is in the psu so has a vdr and a couple of caps as a spike suppressor on it.

All the best
Martin

[PinkFloyd]

That's fine....

[pingu]

Thanks Mike I'll leave it with the 30va transformer as its already installed in the PSU

Regards
Martin