Kevin's PL400 Upgrade

[laatsch55]

Do you have the Phoenix connectors for the mule then?? And have you had any trouble with the connectors not letting the solder flow to both sides??

 

[laatsch55]

Mark most 400's I've been in were like that. They've always had the white from star ground to the terminal strips between the rows of outputs. It always amazed me that they isolated the RCA jack body from ground then ran it right over to the output ground , sometimes bypassed with a small ceramic cap. I mean if the first contact with ground potential is where output current is swirling, how is that good?

 

[mlucitt]

To be honest, I have not seen two of them wired exactly the same. But this is part of the Phase Linear mystique. I can imagine rolling into work at the Lynnwood plant some time around 8:00 AM and having stacks of components and rolls of wire by your bench. You did one amp at a time (and probably followed a check off list) and wired point-to-point until you were done. How many amps do you think they did in a day, maybe 10 amps per person per day? That's my impression, have you heard how they did it from Ed B.?

Here is a shot of the bottom of the board where the Phoenix connectors go. The silver-bearing solder really flows well and I check each connection with a meter after I am done, no problems so far. And now I will check both the top and the bottom of the bias resistor pads on the board!!!
[attachment=0:1z91rz3z]Edge Connectors.jpg[/attachment:1z91rz3z]

 

[laatsch55]

I believe that is what was doing me in on Gibsonians project, and yet on each board i dutifully drilled out the Q6 holes on every board. Must had gotten lucky on a few and managed to get the solder everywhere it was needed. Just finished a Mouser BOM for the ten boards I got this week. Between that, outputs and caps it was a choker.

 

[laatsch55]

Haven't talked to Ed for a couple weeks, must be time.

 

[ksrigg]

Mark,

I did double box the Hafler, and used one box that I had on hand. The outside box was a new one when it left my office. It was also well taped, so I am sorry if it took a hit. I thought I had it packed well enough to make it to you.

As to the Hafler PRO 500, I do have those 33,000 uf Cornell Doublier caps. They are about 3" in diameter and about 4 3/4" long I think...The guy I just pm'ed you about has them as well. I think they are about $60.00 a pair..

So looks like Kevin's PL has blue meters..you are making real progress on it. I gotta get on the stick to keep up with you. I didn't accomplish anything today...worked on the Yamaha K-1020 cassette deck and replaced both belts in it. It will nto FF or REW though. It does PLAY now, but that's it. It is just not meant for me to have a fully functioning Yamaha cassette deck I don't think.

Tomorrow I will get the epoxy and the light bulb tester built...Should have everything in but the probes from China and the MCM order...I hope the protect circuit is here from Don.

Man I can't wait to dig in to the PL, but now it looks like I have to go to Florida and California in the next week and be gone for at least a week. Bummer...Wonder if I can carry on a Phas Linear 400?

 

[ksrigg]

Just hung up the phone with Kevin. He found the ground loop, and it was his TV cable.....Unplugged the cable from XFinity and hum is gone....so now he has to raise hell with the cable company. Anywy he asked that I inform the community that his problem is solved and to thank everyone..

 

[mlucitt]

No biggie on the box, it opened on the side seal where it was glues, not your fault.

That meter you saw is not Kevin's, it is my bench testing chassis. I may have to change the lights because they are so blue, I remember Kevin wanted blue and I just grabbed the first one to put into the amp. I am waiting on caps for his amp. Tomorrow I will be doing some serious work on it.

Have fun in CA. Where are you headed?

 

[Gepetto]

I guessed it was his cable connection. Not a Comcast problem, it is a general problem we all suffer through related to ground looping in the house. Comcast may put an isolator in line to transformer couple it but not sure that works any more in this high speed internet connected world. That used to work when it was just video coming down the cable.

Digital isolators are available from multiple companies to solve this problem. Floating his gear is another option to solve this problem as has been written on this thread.

 

[Gepetto]

Kevin
Here is a link to one of the companies that makes cable isolators. No guarantee or endorsement here as I have not tested any of their products.

http://www.jensen-transformers.com/iso_vid.html

 

[kevin]

Gepetto.... I just discovered this.. When i unplugged my cable out of the wall my hum goes away. When i unplug it out of the tv the hum is still there. My cable runs from the wall to a h.d. cable box and then to the tv. Sounds to me like its gotta be in that cable box. THANK YOU again for the help and the link. I think im going to go turn the plug over on that box and see what that does.

 

[Gepetto]

Do not think that will help Kevin. Do you have an audio feed from the HD cable box to your system? If it is not optical, I recommend that you make it so. The connection that I have from my HD box to my Outlaw preprocessor is TOSLINK. That breaks the hum link.

 

[mlucitt]

Kevin's amp got some attention today. Here is a shot of the new speaker outputs in preparation for the DC Output Protect Board from Don (Wattsabundant):
[attachment=1:s9cb4wjo]Prep For DC Output Protect Board.jpg[/attachment:s9cb4wjo]

This is the installed board, it is a nice fit.

[attachment=0:s9cb4wjo]DC Board In.jpg[/attachment:s9cb4wjo]

 

[Gepetto]

Nice work Mark, very neat.

 

[mlucitt]

Kevin, the old bridge rectifier is gone and now there is a fresh 35 Amp 1200 PIV replacement. Next will be some sweet coaxial wire from the new input jacks to the board edge connectors. Then some minor sheet metal work to install the power jack.

The added black wire is the AC voltage sense for the DC Output Protect board from Wattsabundant.

[attachment=0:6k3l2la0]Bridge Replaced.jpg[/attachment:6k3l2la0]

 

[laatsch55]

Choice!!

 

[ksrigg]

Looking good Mark..

 

[mlucitt]

Progress continues on Kevin's PL400. I have the power jack installed and now I need to wire it up. The question of where to put the chassis ground suddenly confronts me. Rod Elliott recommends running a wire from the power jack to a firm dedicated grounding point on the chassis and also connecting the chassis to the STAR ground along with the CT of the secondary transformer winding. The PL400 does not use a CT secondary transformer, will that matter (other than the split voltage of course).

Thoughts?

[attachment=1:e46k2ltl]Almost There.jpg[/attachment:e46k2ltl]

[attachment=0:e46k2ltl]Power Jack Installed.jpg[/attachment:e46k2ltl]

 

[kevin]

Ok then gepetto... i will get one of thoes this eve... thanks. Now... MARK.... WOW !!! I know thats going to be the best amp that ive ever owned... or will ever own. What would really be great is if i understood everything your telling me about it.. lol... Thank you so much !!!! Again let me thank everyone on here...... Yall have been really awesome to me !!!!!!!!!!!!!!!!!

 

[laatsch55]

But with separate secondary windings in seies the common tie point is a center tap in essence. With the center tap isolated from the transformer frame, it's the same thing.