PL400 II Resurrection

[TapeHeadOne]

Hello everyone,

After my freak mishap converting the 400II with a White Oak input board, I have decided there's nothing for it but repair it, and I'm hoping you good folks will help me succeed.
As I'm going to need only a few parts to hopefully repair the WO board, I decided to take stock inside the 400II.

First thing I've done is disconnect the PS and see if all is well there. And it is, putting out a rock solid 110V after the rectifier. The WO cap kit has also suffered no damage whatsoever.
Now I've turned my attention to the output transistors. I've taken out the rightmost 3 XPL 909's and have unfortunately determined one has not survived. I will also remove and test the other ones, of course. Which is turning out to be a bit of a bastard because I have only metric sockets.

But this leads me to the first conundrum. XPL 909's are difficult to find in Europe and therefor expensive. From what I've seen asking prices are in the region of 20 Euro, and there are probably better choices now.

So in order to get this show on the road, are there readily available drop in or near drop in replacements for my Quasi 400II ? Which ones would you recommend ?

No, I'm not going full comp.

Thanks,

Pete

 

[laatsch55]

On-Semi 21196's...

Power supply after the rectifier should be +/- 80 volts dc...

 

[mlucitt]

If you give us your address, we can send you the replacement transistors as Lee mentioned above for our cost ($7.00 each) plus shipping (or you can order them from Mouser) here: https://tinyurl.com/y4nzon8l
After testing the rest of them, you may need more than three. But, those original transistors are very old and the replacements are so much better suited to the WO Control Board. So, consider replacing all twelve of the old XPL 909's after you get the amp sorted out.

 

[TapeHeadOne]

Desoldered the rectifier. 120VAC over the two red wires on the rectifier input. With the rectifier connected it's 110 on the AC and 110 on the DC. Not good. Suggestions for a suitable replacement ?

Checked the output transistors. 2 straight through (0Ohm between B and E) on the right channel . Left channel all OK. But the On-Semi MJ21196G is less than 6 Euro when you order 10+.

But I need to get everything so I can avoid paying 20 Euro shipping if I forget a 30 cent resistor.

Peter

 

[laatsch55]

If you measure to ground on each dc leg of the rectifier 55 volts is about right. At the +/- cap terminals you should get +/- 80 volts.
DC voltage should be AC times 1.4 at the cap terminals..

 

[MarkWComer]

Is your transformer wired for 120 or 220 VAC?
That may account for the high voltages.

 

[TapeHeadOne]

Wired for 220, but our grids have been 230 50Hz for donkeys years. 120 AC before the rectifier, should have 160 on the output with nothing connected. Is the black wire a central tap for the +/- 80V ?
Anyway, a new rectifier is 10 Euro, so in it goes. Pete

 

[laatsch55]

Correct Pete..

 

[TapeHeadOne]

If you give us your address, we can send you the replacement transistors as Lee mentioned above for our cost ($7.00 each) plus shipping (or you can order them from Mouser) here: https://tinyurl.com/y4nzon8l
After testing the rest of them, you may need more than three. But, those original transistors are very old and the replacements are so much better suited to the WO Control Board. So, consider replacing all twelve of the old XPL 909's after you get the amp sorted out.

As I mentioned in the other thread, importing from the U.S. is really a last resort, as surcharges by our customs and VAT people together with shipping cost are going to be horrendous. But thank you kindly for the offer.

 

[laatsch55]

Where are you located Pete?

 

[TapeHeadOne]

The great Kingdom of Belgium, known for the best beer in the world, the best fries in the world, and more governments per square inhabitant than you can poke a stick at.

 

[laatsch55]

LOL!! Ok Pete...welcome to Phoenix!! Have fun.....we do...

 

[Bradrock]

And I thought it was Waffles...........

 

[Gepetto]

Belgium is the worst lately for custom clearance. Brussels is reacting harshly to the US tariffs by being extra tough on imports.

 

[MarkWComer]

The great Kingdom of Belgium, known for the best beer in the world, the best fries in the world, and more governments per square inhabitant than you can poke a stick at.

...and chocolate. Don’t forget chocolate!

 

[laatsch55]

...and chocolate. Don’t forget chocolate!

Oh yeah!!

 

[TapeHeadOne]

Belgium is the worst lately for custom clearance. Brussels is reacting harshly to the US tariffs by being extra tough on imports.

Not really, that's just a fable for the media. Thousands of packages are imported every day and since we're in 'the EU' everything that enters the country to be routed to somewhere else needs to be cleared too. In reality only very few packages are checked by customs themselves. Everything else is cleared by the carrier. However, if you send by USPS for instance, clearance is done by our bPost postal services. And although they were privatized years ago, the state still holds 51% of the shares, and the employees still have (to all intents and purposes) 'public service' contracts. Not only are they basically impossible to fire, they also have many many paid vacation days, and they're all taking them in July and August during their kids' school holidays.
And since they're public servants, they can't really be buggered about service to the public, so when there's a small problem they don't contact the recipient, they just put it aside an wait until the recipient gets impatient and contacts them instead.
Nothing more nefarious than that.

Meanwhile, back in the lab...

 

[TapeHeadOne]

Some pictures of the burnt PL board? I think I may have gotten away with murder as only the (R30R?) pads seem severely damaged. As far Ias I can see, there's only two traces and hey can be hardwired. Pleas correct me if I'm wrong. That bottom right transistor also measures real funny.

As non of the output transistors on the left channel were damaged, I may have gotten lucky and everything is intact here.

 

[mlucitt]

That is a lot of heat transferred to the Control Board. Melted the solder?

Not really, that's just a fable for the media. Thousands of packages are imported every day and since we're in 'the EU' everything that enters the country to be routed to somewhere else needs to be cleared too. In reality only very few packages are checked by customs themselves. Everything else is cleared by the carrier. However, if you send by USPS for instance, clearance is done by our bPost postal services. And although they were privatized years ago, the state still holds 51% of the shares, and the employees still have (to all intents and purposes) 'public service' contracts. Not only are they basically impossible to fire, they also have many many paid vacation days, and they're all taking them in July and August during their kids' school holidays.
And since they're public servants, they can't really be buggered about service to the public, so when there's a small problem they don't contact the recipient, they just put it aside an wait until the recipient gets impatient and contacts them instead.
Nothing more nefarious than that.

Meanwhile, back in the lab...

Even if we are sending you a "gift" or "samples"? Is there no way around the customs and VAT even if the declared value is 1 Euro? Maybe we can barter for chocolate? 12 transistors for 1 Kg of milk chocolate, fair?

 

[Gepetto]

Some pictures of the burnt PL board? I think I may have gotten away with murder as only the (R30R?) pads seem severely damaged. As far Ias I can see, there's only two traces and hey can be hardwired. Pleas correct me if I'm wrong. That bottom right transistor also measures real funny.

As non of the output transistors on the left channel were damaged, I may have gotten lucky and everything is intact here.

R30 is the RevE board equivalent to the R76 resistor that Lee fused open on the RevD board that he has.