phase linear 400 voltages change

[Gepetto]

Yep , you are right . This amplifier just have 4 finheatsink only and a PCB Is Pl400c

If it has the 400C it is very early and the bias transistors were not mounted to the back wall as they should be, instead they are on the control card similar to the PL0171 control card in early PL700's.

 

[Gepetto]

What is the end bell? You mean the tranny cover plate?

It is a big die cast element on the inside of the transformer where it mates to the chassis. The die cast reaches inside and forms a curved cradle to mount the caps to and holds the bridge as well and serves as an inertial heatsink for the bridge rectifier.

 

[laatsch55]

I just pulled the faceplate off my first gen. 400 and it looks exactly like these pictures. BR mounted to the side, no bell on the transformer. Not sure about the dual voltage, it's definitely been running on 110V in an American market all its life. Ser. #743-110A. I'll post some pics for comparison if anyone needs to see them.

Which driver board does it have??

 

[changdangnz]

I just bought it from USA and shipping it to australia. I will open a capacitors filter out to get a photo more clearly on tomorrow.

 

[laatsch55]

If it has the 400C it is very early and the bias transistors were not mounted to the back wall as they should be, instead they are on the control card similar to the PL0171 control card in early PL700's.

After reading this Joe, I couldn't remember working on a PL400C with the bias transistors on the board. So, I called Ed, and Ed couldn't remember working on a PL400C board with the bias transistor on the board either. So, he walked over and talked to Dean. Dean couldn't remember working on a PL400C with the bias transistor on the board either. However, there does exist a schemo showing that. Dean thinks there may have been one or two amps like that----MAYBE. Ed has 4 examples of the PL400 board and ALL are different. It seems in the early production runs there were revisions left and right with little documentation. Ed has a theory that the amps that had bias transistors on the heatsink BUT still showed an MPS 5172 were perhaps in those halfass "clips' and not the full blown P strap. And, the 400 were produced for approximately 2 years with the bias heatsinked BEFORE the 700B came out with heatsinked bias transistors. So the 700 Series 1's were produced quite awhile with board mounted bias transistors, along side 400's being produced WITH heatsink mounted bias tranny's......normal for PL.....

 

[laatsch55]

I just bought it from USA and shipping it to australia. I will open a capacitors filter out to get a photo more clearly on tomorrow.

What is your name? I would rather type your name than your username. Your username is not single finger typer friendly....

 

[changdangnz]

I got a 2 cooling fin come with amplifier. But i had been check a holes on the back is not line up with a holes on cooling fin .

 

[laatsch55]

I got a 2 cooling fin come with amplifier. But i had been check a holes on the back is not line up with a holes on cooling fin .

What??

 

[changdangnz]

My name is chang . Nice to meet you lee. I'm a mechanical engineering but not electrical engineering. I can solve a problem on cnc or on car but not on amplifier . It is so exciting to me and i want to learn it.

 

[laatsch55]

You came to the right place Chang!! Looking forward to helping you...

 

[changdangnz]

Yes , a seller send 2 cooling fin with a amplifier as well . I am try to put it on to the back of amplifiers but a holes is not line up.

 

[Fishoz]

Have been waiting for you to introduce yourself Chang. Welcome to Phoenix. This is the Phase Linear think tank, many members have a wealth of info. Have a bit of fun poking around.

 

[laatsch55]

Yes , a seller send 2 cooling fin with a amplifier as well . I am try to put it on to the back of amplifiers but a holes is not line up.

The output transistor holes or the holes for the bias transistor?

 

[changdangnz]

i have no idea , i just take a photo so i think you know it well than me. I bought this amplifier from TMZ2 on this forum .

 

[laatsch55]

Did those heatsinks that are separate from the others, are they off of this amp? Or are they some extras he sent??

 

[changdangnz]

A seller told me this heatsink is come with this amplifiers when he is boight it for preproduction faceplate. I think it's not belong to this amplifiers

 

[NavLinear]

I am try to put it on to the back but a holes not line up.

I believe the nurse can help you with that.

Welcome Change to Phoenix. I could not resist the English as a second language jibe as I work with a few people that speak a native tongue other than English. There are a few members here that have a really good understanding of the Phase Linear amplifiers that will help you get your unit working.

 

[NavLinear]

i have no idea , i just take a photo so i think you know it well than me. I bought this amplifier from TMZ2 on this forum .

View attachment 22063

Those photos are a bit too small to see - at least for me. Can you post some a bit larger?

 

[marcok]

Welcome aboard , Chang !
Ciao Marco

 

[Northwinds]

I wondered if the two smaller heatsinks could be used on a 4 fin to convert to 8 fin?