WO-08 ? Bridge rectifier? And T 79015P?

[thekid777]

Hi
I'm not sure if it's the bridge rectifier WO-08 ?
Can you confirm correct replacement is nte 5306?
Thank you!

 

[JohnRoberts]

OK IIRC the W0_X series was bridge rectifier with equivalent of 4x 1n400x diodes inside.  elsewhere I see w0-8 rated 800V 1.5A

5306 looks like 800V 1.5A bridge, so looks like they are equivalent.

JR

 

[thekid777]

Thanks John!

Could you advise me please:
I have to change the regulators in the psu that give +15v and -15v to the modules.
It's ok to put together a 7915 with 1,5A of output current max along with a 7815 which have 2A of max ouput current or both should have same max output current?
The psu feed 12 modules and each module need 150mA.
Thanks for your help!!

 

[outoftune]

hi, im not john but...

did the PSU originally have 78/7915 regulators in it or are you building a new psu?

 

[JohnRoberts]

Thanks John!

Could you advise me please:
I have to change the regulators in the psu that give +15v and -15v to the modules.
It's ok to put together a 7915 with 1,5A of output current max along with a 7815 which have 2A of max ouput current or both should have same max output current?
The psu feed 12 modules and each module need 150mA.
Thanks for your help!!

12x 150ma = 1.8A so more than 1.5A max. Perhaps use multiple regulators and split up the power feed 5 and 5.

JR

 

[mjrippe]

In that case you may also want an overrated diode bridge as well.  A 3 amp bridge will be almost the same price and will run cooler.

 

[thekid777]

Thanks guys for your feeback
Yes these regulators was already there
I'm just repacing some parts as she is quite old (around 1989)
I notified there was not exact voltage on the +15v and -15v which feed the mic pres.
It was more like 15,4 and - 15,2 and I think it's quite important to have precise voltage here.
So I replace the old diode bridge, along with other diodes and the regulators to start fresh and for a long time.
I asked myself as well about the 1,5A limit but it's what was there and I can't find a negative -15 regulator (7915) up to 2A. The higher I can find is 1,5A...
For now it's not a problem to put that 7815 (2A) along with the 7915 (1,5A) together in your opinion??
Thanks!!

Btw I can't understand why Mr Rupert Neve which built this would have forgotten to make a psu not powerful enough?

 

[JohnRoberts]

Thanks guys for your feeback
Yes these regulators was already there
I'm just repacing some parts as she is quite old (around 1989)
I notified there was not exact voltage on the +15v and -15v which feed the mic pres.
It was more like 15,4 and - 15,2 and I think it's quite important to have precise voltage here.

Actually no it isn't. Common 3 terminal regulators are often a few tenths of volt one way or the other. More important than precise voltage is that they do not drop out of regulation and add hum to the DC supply voltage.

So I replace the old diode bridge, along with other diodes and the regulators to start fresh and for a long time.

Diodes generally work or they don't. Old tired capacitors could cause higher ripple voltage perhaps corrupting regulated supply with hum. 

I asked myself as well about the 1,5A limit but it's what was there and I can't find a negative -15 regulator (7915) up to 2A. The higher I can find is 1,5A...
For now it's not a problem to put that 7815 (2A) along with the 7915 (1,5A) together in your opinion??
Thanks!!

Btw I can't understand why Mr Rupert Neve which built this would have forgotten to make a psu not powerful enough?

If it was working before, i guess it was powerful enough. Perhaps the current draw spec is conservative.

JR

 

[thekid777]

Thanks John!

It's a problem technically to have regulators with different max ouput current together?

 

[thekid777]

Old ones and replacement

 

[JohnRoberts]

No, what matters is if the regulator does not have enough current output capability for the circuit, having more is always OK.

JR

 

[thekid777]

Super! Thanks!

 

[thekid777]

Hmm one last thing..

I'm surprised by the way smaller new diode bridge next to the older one!
These are smaller now like caps?
Don't know as well what pbf stands for? Original as just kbpc802...

 

[JohnRoberts]

pbf probably means lead-free.

Size may not mean much, with a heat sunk bridge it is more about thermal resistance between diode junctions and external heatsink than thermal mass or direct radiation from diode bridge. If the resistance from junction to sink is lower, they can reduce size and get equivalent performance.

JR

 

[thekid777]

Thanks for the informations! cool

 

[thekid777]

Btw she seems happy now...
Still finding +15,33 but perfect -15 now
John, I was believing it's really important to have these perfect as this is for audio voltage rails

Ps: your resotune looks really cool!!