New PL 400 Series II build

Wombat said:
Going back and triple checking my wiring. Is there a diagram showing the wire connections from the back planes to the Phoenix
Connectors on the PL 14-20? I have wired them according to pictures posted for two builds. My PL 14-20 was converted from quasi to full. I have instructions for the quasi connections but would like them for the full as one more check. Thanks, and have a great 4th everybody!
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Hi Don
They are straight 1:1 connections except for pad 5 on the control board. All connections are detailed in the documentation that I sent to you. Refer to the complete wire lists on page 37 and 38 of the file named Assembly Notes for the PL400 Backplane_RevE PCB+
 
I have downloaded and printed every document I have received along with posts and emails pertaining to the full comp conversion and all the other PL 400 upgrades I have done. Printed relevant pictures on photo paper. Put everything in a three ring binder for ease of reference. Still missed it. Probably have too much paperwork! Thanks!
 
Apparently, I am dumber than I thought. When I pre-installed the lower row of transistors just to see how they work, the pins may have actually not gone into in the holding cups. Now on the final, I can't tell. Joe's excellent materials reference aligning the pins. I have a magnetic holding tool. How do you actually check to make sure the pins go into the cups? Thanks in advance.
 
Wombat said:
Apparently, I am dumber than I thought. When I pre-installed the lower row of transistors just to see how they work, the pins may have actually not gone into in the holding cups. Now on the final, I can't tell. Joe's excellent materials reference aligning the pins. I have a magnetic holding tool. How do you actually check to make sure the pins go into the cups? Thanks in advance.
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Hi Don
You look at the pins protruding from the top of each socket cup. Each pin will push out the OFP plug that caps each socket cup.
 
So, install row 4, put PCB in, test row 4, take PCB out, install row three, put PCB back in, test, and repeat for row 2 and 1?
 
Wombat said:
So, install row 4, put PCB in, test row 4, take PCB out, install row three, put PCB back in, test, and repeat for row 2 and 1?
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No Don, once the control board is added in step 21-25 of the Backplane bring up instructions, the instructions that follow call for discharging, adding a row at a time and retesting.
 

Attachments

Got that, but you can't see all the socket cups with the PCB board installed. At least I can't see behind it.
 
OK. Install of PCB does not have to be final for testing. See what happens . . .
 
How long does it take others on here to install four transistors? I am over two hours and only have bent pins. I am wondering if something else may be going on here. Thanks!
 
Wombat said:
How long does it take others on here to install four transistors? I am over two hours and only have bent pins. I am wondering if something else may be going on here. Thanks!
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About a minute or two for each transistor. Use a magnetic pickup tool as pictured in the instructions. Provide plenty of light. Place the amp face down on the bench (heatsinks facing upwards) and ensure that the backplanes have been aligned properly so that each transistor socket is aligned through the chassis and the heatsink. Loosen and realign the backplanes using the upper and lower standoffs until this condition is achieved. This is where the assembly aid hardware is used, to get the backplanes aligned properly. After aligning, retighten the upper and lower standoff screw to lock the position. You will need to slightly back off on the 6-32 nut on the upper standoff and the 4-40 nut on the lower standoff while aligning. Again, when the backplanes are aligned, these 2 nuts must be retightened to lock everything in place.

Once you get that alignment proper, the transistors will install much easier. Don't attempt unless the backplanes are properly aligned.
 
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Everything is aligned with assembly aid. Perfectly centered on all 16. Put just the bolts through and backed them out. Using magnetic pick up tool. Can't get transistors to install in any position. They just push the backplanes away. Can tighten the screws, but it just bends the pins. Almost as if something is blocking the holes the pins go through.
 
The last outputs I received had blunter tips than earlier transistors. I precisely align them to the gold cups early in the build, but, you can also align them to a old original socket.
I usually have one that just won't drop in, so I sit it aside, to give it a rest. Eventually they all slide in. Some times one pin is in, so cock it a little sideways while you rotate it feeling for the other pin to find the hole. Just takes practice and patience. Align the pins to a old socket and be gentle. Seen lots of dented outputs on eBay amps from them being banged in.
Use a magnet on a stick to seat them flush, gently, then screws.
 
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They'll slide in provided the gold cups are on the correct side of the board and holes aren't soldered shut.
 
I have been to the point of filing the tips to a sharper point sometimes. On my later builds I will test fit to each specific location while the backplane are still on the bench. Then number them and keep them in order until its time..
 
Many great ideas. Beats my hand sledge solution. Thanks to all!
 
Wombat said:
Many great ideas. Beats my hand sledge solution. Thanks to all!
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Remember when you were young and did your best work in the dark?

When you get the feel of it, you will be able to discern when the leads click into the opening holes and then you will be surprised at how easy they just slide in.
 
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