phase linear 400

[George S.]

Gene and George
I pulled one bolt out and I would have to drill hole's in both transformer covers and it still might not work?

So its a no go for me , yours might have bigger holes.
So for me I don't want to take the change of loosing up anything in the inside the transformer (metal and Varnish) I did tighten up the bolts and they were a little loose.

Not sure what you mean, but, if your using those step washers, or the double heat shrink, or Don's "roll your own bolts in packing tape", you may have to loosen all the bolts first.
Go ahead and support it underneath so it'll stay level, remove all bolts being carefull not to stress the wiring. Pull the transformer bell off. Test the holes in the bell, test the holes in the transformer. There may be burrs on the bell holes that need filed or a bit run through.
Do not use anything made of metal on the transformer as we want to keep those plates seperated and a knick could bridge them. If there's a gob of varnish in a hole or rust, clean it out with a wood dowel.
The only issue I had was with trying to use straws, too damn tight. The double layer of heat shrinked bolts slid right in, same with the step washers.

 

[George S.]

i can do that too....lol
thanks....
i am curious why georges transformer and rectifier without caps measures 80v,,,,and mine is only 60v....
i think i will add caps before i read voltages again....
should be easy to pick the best one...

Gene, if your line "wall" voltage is low, then your VDC will also be low. Mine is usually around 118 VAC. Start using VAC or VDC when stating voltage. Glad we broke you from "chips".

 

[George S.]

Steve, pull the bolts, then the bell. It's not going to fall apart. Just plan ahead so it's sitting where you want it, to work on it easily and wiring isn't stressed. It's really no big deal. It's a big hunka steel and copper and will remain so for a long time. Very easy to do.

 

[MusicSteve]

Not sure what you mean, but, if your using those step washers, or the double heat shrink, or Don's "roll your own bolts in packing tape", you may have to loosen all the bolts first.
Go ahead and support it underneath so it'll stay level, remove all bolts being carefull not to stress the wiring. Pull the transformer bell off. Test the holes in the bell, test the holes in the transformer. There may be burrs on the bell holes that need filed or a bit run through.
Do not use anything made of metal on the transformer as we want to keep those plates seperated and a knick could bridge them. If there's a gob of varnish in a hole or rust, clean it out with a wood dowel.
The only issue I had was with trying to use straws, too damn tight. The double layer of heat shrinked bolts slid right in, same with the step washers.

Thanks
I tried the straw so that's why it did not work and this is Good to know, this unit had no rust on the inside of one of the Bolt so for now I will leave it as is But I'm doing a bunch of other 400II , if a Have some bad ones or a little more time and they have a lot of rust I will do this. also I'm not starting from scratch like you are and that makes it easier to work on and Carefully take it apart.

Testing - if you have a load resistor and bring it up to before clipping, do you hear a high pitch sound coming from the Transformer?
Pics of voltage and amps Don't know what the maximum amps is for the 400II?

 

[George S.]

I had little success with a straw.
https://forums.phxaudiotape.com/threads/insulating-wopl-400-transformer-bolts.9514/
As for your high frequency oscillations, I don't know. When I was stress testing my 400 S1 to get the temperatures for Gene, the limiting factor was driving my preamp into distortion or overheating the speakers. The WOPL wasn't the limiting factor.
I see your 400 isn't a full WOPL. This is perhaps the issue.
I read somewhere that PL added ferrite beads to the back wall to combat high frequency oscillations, but were only partially successful. You'll probably see them on a S2.

 

[gene french]

when i first played the 200 s1...it had a horrible hum...sounded like an ac hum to me....turned out technically it was...another bud told me to tighten the transformer...it was like a miracle...i had absolutely no idea a transformer could make that sound....lol

 

[MusicSteve]

I had little success with a straw.
https://forums.phxaudiotape.com/threads/insulating-wopl-400-transformer-bolts.9514/
As for your high frequency oscillations, I don't know. When I was stress testing my 400 S1 to get the temperatures for Gene, the limiting factor was driving my preamp into distortion or overheating the speakers. The WOPL wasn't the limiting factor.
I see your 400 isn't a full WOPL. This is perhaps the issue.
I read somewhere that PL added ferrite beads to the back wall to combat high frequency oscillations, but were only partially successful. You'll probably see them on a S2.

So you think this is high frequency oscillations?

I need to test my other 700II and see if it also does it, as I recall I think they all did it? but I not sure since it been 20 years ago. I will have to test the 400II w my original board and my PL14_20G1 #1 board ,using my #2 board

What I have read the original output Transistors did not have this problem but when they switch to the Faster Newer ones they started to see more problems.

 

[MusicSteve]

when i first played the 200 s1...it had a horrible hum...sounded like an ac hum to me....turned out technically it was...another bud told me to tighten the transformer...it was like a miracle...i had absolutely no idea a transformer could make that sound....lol

As these get older, new problems will pop up and every little tip Helps

 

[George S.]

Well, best tip I can offer is install the WOAD backplanes. Joe has this all figured out.

 

[gene french]

Gene, if your line "wall" voltage is low, then your VDC will also be low. Mine is usually around 118 VAC. Start using VAC or VDC when stating voltage. Glad we broke you from "chips".

i have meters everywhere here...output of solar panels feeding my breakerbox....outputs of 100ah battery backup system for internet, tv, etc...we get several glitches per day...all my line voltages say 122 volts...as you can guess...that makes the 220 side a tad high...they do that here because the grid is different....they have 38400 volts on the primary on the poles reduced to 19200....at intervals they drop a transformer...and they run secondary lines on same poles using spreader pipes so the wind does not short it out...looks like ladder coax...lol
the houses tap off of that secondary wiring...not the transformer...resulting in long runs of secondary to each house...as most transformers may service multiple homes....they intentionally set the secondary voltage high...as they consider 125 meters the limit on a secondary run...thats a long way...they connect their seconday from their lines to your meter pan with #8 copper....
most houses use a 100 amp 220v knife switch as a cutoff...after i melted a few...i rewired mine with #6 copper (i had to beg for that) put in a 200 amp meter pan with cutoff breaker at the pole...not in the house...my house breaker pan is eaton but without a main cutoff...its outside in the pole...lol
i have an eaton type 2 whole house surge supressor and type 3 on all digital appliances...i think only the washer doesnt have one...get messy sometimes....lightning did get through once...got supressor and microwave ... only one appliance in 15 years...not so bad...

 

[gene french]

Well, best tip I can offer is install the WOAD backplanes. Joe has this all figured out.

you were right george...i am so glad i went all the way with the new chassis...backplanes...new complimentary outputs, etc...its better to bite the bullet and get er done...even got new input jacks from watts....i know i would never have been satisfied until i did...i think you knew that too...joe was just sitting back with a big grin...he also knew i would never have been satisfied...lol...he was gonna let me learn at my own pace...and you know...i appreciated that...everything worked out...just as it should...lol
it always does...

 

[George S.]

https://www.mercurymagnetics.com/transformer-rust-friend-or-foe/

 

[gene french]

https://www.mercurymagnetics.com/transformer-rust-friend-or-foe/

interesting ..

 

[George S.]

Yeah, if I had a rusty one, I'd clean it with a plastic bristle brush and recoat it in varnish.

 

[gene french]

goooooddd mooorrrrnnniing phoenix...
chillin with kitty, daisy, and lewis

 

[gene french]

modi 3?????

 

[VSAT88]

Can also make your own. Switchcraft RCAs and coax.

This is what I do. Belden Mic. cable and Switchcraft phono/RCA ends or the same for XLR with "gold plated" pins. I just buy a bag of em and keep it all around for when I get ready to make some up.

 

[George S.]

I was looking at the Belden 8402 cables on the Bay the other day and reading about it on the forums. But I have a question about use with RCAs. What do you do with the extra conductor?
Use both conductors as one for signal and shield for ground?

 

[VSAT88]

Might want to see how the custom cable makers are making them for sale. I've seen hand made high zoot ones on the Bay. In the past Joe has said that Belden RG-316 is very good for interconnects. It's what I and others use on the WOPLs.

Damn it now I gotta try this...

 

[gene french]

I was looking at the Belden 8402 cables on the Bay the other day and reading about it on the forums. But I have a question about use with RCAs. What do you do with the extra conductor?
Use both conductors as one for signal and shield for ground?

couldnt you make two cables???
left signal, right signal, common ground/shield???