PL 700 Pro Build

[George S.]

I can clean up those copper plates with my WES 51, takes about 40 seconds..

Do you heat it up and wipe it off with a rag?

 

[laatsch55]

Get it liquid, then shake it..

 

[George S.]

Doing the updates to the 400 S1 this morning. After sleeping and thinking about the RCAs I did yesterday, I think leaving out the toothed washers and soldering is the way to go.
Going back into the other two amps today and pull the toothed washers.

 

[J!m]

I think toothed washers would be fine into soft copper, but the ol' belt-n-suspenders approach works too.

 

[George S.]

Calling the 700 Pro build finished after getting the longer standoffs installed, and Joe's updates done. Got the RCA ground tabs soldered to the copper plate. Thanks y'all. Later.

 

[Randall Daniels]

I always thought the meters should be accurate like a speedometer on a car.
I do like the meter attenuation switch on the 700 that supposedly matches the 700s meters to a 400s full scale meters. But, you know, I might be wrong about this. I don't know.
Any how, I'll probably put the original resistors back into the 400 S1 so they accurately read 100 watts at the 0 db 100 marking on the meter faces. That's how they designed it, much smarter people than me.

Anyone have the par number of the 700II meter attenuation switch, been searching and all I find is the power switch. (That is unless I am blind which is a distinct possibility.)

 

[George S.]

Looks like the power and meter range switch came as a assembly "2-Station ass'y (power & range) ...129-0093-0" mounted on the bracket.
Both switches are Alps, and secured to the mounting bracket with bracket extensions that are crimped to secure the switches.
The meter range switch is very similar to the Alps push button switches in the PL2000 preamps.
These can be taken apart and cleaned, just watch for the spring loaded small parts. I don't remember seeing a part # on my meter range switch, nor see one in the many photos I have of it during the build.

 

[George S.]

Plenty of Alps push button switches on the Bay, I even see a couple "TV" power switches that would probably work for the On/Off switch
Just make sure you get a "locking" version as some are momentary.

 

[Gepetto]

Looks like the power and meter range switch came as a assembly "2-Station ass'y (power & range) ...129-0093-0" mounted on the bracket.
Both switches are Alps, and secured to the mounting bracket with bracket extensions that are crimped to secure the switches.
The meter range switch is very similar to the Alps push button switches in the PL2000 preamps.
These can be taken apart and cleaned, just watch for the spring loaded small parts. I don't remember seeing a part # on my meter range switch, nor see one in the many photos I have of it during the build.

Hey George
You know those resistors come off the meter attenuation switch when you use the White Oak Cylon boards correct? That feature is built into the Cylon meter boards

Pin7Attenuator switch wire 1 (remove 120K ohm resistor usually applied between the attenuator switch terminals)

Pin8Attenuator switch wire 2 (remove 120K ohm resistor usually applied between the attenuator switch terminals)

 

[George S.]

Yes sir, that was the original wiring. I've learned to photo pretty much everything electrical before I take it apart. Sure beats drawing it all out like before cell phones!
Found a potential power switch and a meter switch(although it's a little long with extra contacts).
Links follow:
https://www.ebay.com/itm/NOS-HAFLER...2349624.m46890.l49286&mkrid=711-127632-2357-0
https://www.ebay.com/itm/Alps-SDU3P...2349624.m46890.l49286&mkrid=711-127632-2357-0
Many others are listed.

 

[George S.]

Joe, here's a photo with the resistors removed. Thanks for noticing and questioning this! I seldom get this stuff correct the first time.

 

[Randall Daniels]

Yes sir, that was the original wiring. I've learned to photo pretty much everything electrical before I take it apart. Sure beats drawing it all out like before cell phones!
Found a potential power switch and a meter switch(although it's a little long with extra contacts).
Links follow:
https://www.ebay.com/itm/NOS-HAFLER...2349624.m46890.l49286&mkrid=711-127632-2357-0
https://www.ebay.com/itm/Alps-SDU3P...2349624.m46890.l49286&mkrid=711-127632-2357-0
Many others are listed.

I will keep searching, but that Hafler will work just overkill. Went through Alps catalog and no more bracket slide mount crimp types.

 

[Randall Daniels]

Yes sir, that was the original wiring. I've learned to photo pretty much everything electrical before I take it apart. Sure beats drawing it all out like before cell phones!
Found a potential power switch and a meter switch(although it's a little long with extra contacts).
Links follow:
https://www.ebay.com/itm/NOS-HAFLER...2349624.m46890.l49286&mkrid=711-127632-2357-0
https://www.ebay.com/itm/Alps-SDU3P...2349624.m46890.l49286&mkrid=711-127632-2357-0
Many others are listed.

I will keep searching, but that Hafler will work just overkill. Went through Alps catalog and no more bracket slide mount crimp types.
How about this one, anyone have a switch pack out?
https://www.ebay.com/itm/3237374935...A%3D|ampid:PL_CLK|clp:2047675&epid=9030427567

 

[MusicSteve]

I have been buying these for my Pioneer RG2, took a long time to find them.
https://www.ebay.com/itm/283103416891
and also the 2-pole TBD (not for AC)
https://www.ebay.com/itm/254208880110

 

[J!m]

Can be had new from Mouser…

I used similar switches on my phono preamp.

 

[Randall Daniels]

Ended up getting these, even correct color....
https://www.ebay.com/itm/144355158244

 

[George S.]

Thanks for the update Randall, those look very good.

 

[MusicSteve]

Ended up getting these, even correct color....
https://www.ebay.com/itm/144355158244

looks Good, Key word is 3-Way Independent sw's ! good find.
also when you get them do slide into the PL bracket?
The newer one like I posted w Pioneer, I had to modify and enlarge the original SQ bracket (not to easy to do, but possible) I will have to check if they slide into the PL bracket w/o modify it.?

Side Note (not theses) watch out for the multiple sw's ones , I took them apart and find that their all Momentary SW and they have a rod that locks them in one at a time , I think their call Piano type.

 

[WOPL Sniffer]

Jim, you are so right!
Got the IEC socket installed, very tight, but fits well after a little massaging. The right most heat sink is bolted in, and I can just slip a piece of paper between the socket and heat sink.
That heatsink is held in and indexed with Joe's stepped nylon washers and assembly bolts which replace the original output transistor sockets and screws. These are tighter tolerance than the original output transistor sockets and screws. Due to the tighter tolerance, the bottom two holes between the chassis and heat sink are slightly off and won't take the step washer.
Next step is to drill IEC socket retaining holes sized for pop rivets. Then, mock up the heatsinks on the chassis for best alignment with the nylon step washers, number their positions and orientation for future assembly, and carefully ream out any misaligned holes.
Joe's instructions detail how to do this with drill bits, but I use a small tapered reamer, and do it now, not later.

So there ARE fitment issues. Guess I'll have to think about new chassis' and then the dimpled portion of the face plate/chassis will be an issue.

 

[George S.]

So there ARE fitment issues. Guess I'll have to think about new chassis' and then the dimpled portion of the face plate/chassis will be an issue.

Yep, if you think that's a real issue. Was overcome on all 3 of my WOPLs. All three had alignment issues with that bottom right output. Used a drill bit on my two 400s and a tapered reamer on the Pro. Really not a big issue to me. I'm partial to the original chassis. The Pro had the typical bends beside the transformer. Built a simple wooden lever press in the garage on a workbench and massaged it back straight. Then filled and relocated some screw holes to make a stiffer structure.
I like reusing the original chassis and original paint or anodizing. I don't mind the patina.