My First Phase Linear Restore- New Guy to the Forum

[laatsch55]

Mike, I've got Phase Linear's factory load they used in Engineering, and it's a full 2,000 watts. The 250 watt 8 ihm steel cased non-inductive are a good choice, but you can get away with a 100 watt in ice cold distilled water or mineral oil(done both the water is less messy)....

 

[mjstriker]

Mike, I've got Phase Linear's factory load they used in Engineering, and it's a full 2,000 watts. The 250 watt 8 ihm steel cased non-inductive are a good choice, but you can get away with a 100 watt in ice cold distilled water or mineral oil(done both the water is less messy)....

Ya I saw some othe pics of your factory load. Pretty sweet set up. I'll try the water first. The more I have been listening I think the channels are equal and it is mostly speaker placement that is affecting the sound. All in all it would nice to confirm and would be pretty sweet to see how many watts she is pumping out. Right now just enjoying the sweet sound

 

[laatsch55]

What do you have for rail voltage, bet I could get pretty close...

 

[mjstriker]

What do you have for rail voltage, bet I could get pretty close...

If I recall correctly, I think it was in the 81-82 Vdc range (bakc on nights so my brain is a little scattered at the moment)

 

[laatsch55]

Ot'll be right at 260-265

 

[Wayne G.]

I agree...WHAT DIFFERENCE COULD IT POSSIBLY MAKE NOW?>??

Can you believe the gall of that bitch when she spoke before Congress?/ There's some loved ones and relatives where it makes a difference. That administration wasted two seals and an Ambassadors lives for an election....they need to be left in a similiar situation.... then tell me what difference it would make....and then talking individeally to the families promising to "get the guy that made the video"......ya got me started now....and the sad part....they all said it with a straight face.... wasn't their first lie.....

Dammm, Lee I like your politics!

 

[laatsch55]

Democrat, Rebublican, Undependent, Libertarian, BULLSHIT IS BULLSHIT and they need called out on it...

 

[mjstriker]

Been off the grid for a bit. Work had been hitting me hard the last month. Finally was able to get a little above water and relax this weekend.

Have the WOPL'd 400 running duty in the house powering my KLH Model 5. Super sweet sound!! Been working on the Harmon Kardon Citation 16/17 in the garage. The 16 I have been working on for a while now. Most everything has either been replaced and upgraded on the unit minus the resistors and a couple diodes on the driver boards. Took me a while to get the bias and offset to stabilize but now the unit runs rock solid and it sounds great too. It definitely gives the 400 a run for its money sound wise but definitely not when it comes to pure power.

The 17 is basically what I worked on the most. Opened the unit and gave it a good cleaning and replaced all caps on the power and output board. Splurged a little and got some fancy non-polar mundorf's for the output board. Using this now to feed the 400 in the house and the whole set up sounds pretty awesome. Everything is real crisp, clean and defined. I am really enjoying the music and really feel like I can pick out each instrument.

If anyone is interested in the HK Citation 16/17 overhaul I can post some pics in another thread.

Now that I have my two main amps up and running well I am stuck with just one preamp (HK 17). Decided to try my hand again at the PL 2000 series I. This unit has been the royal thorn in my side. Ended up replacing the two chips located on the adapter thinking I might have fried them in my previous attempts to fix this pre. Well it didn't changed anything. Still getting DC at the outputs. I am getting DC coming off pins 4 and 12 of the IC which shouldn't be happening. Spent forever trying to figure and why as I know now it can't be the IC. Was messing with the treble and bass controls and found that adjusting both left and right bass alters the DC. If I adjust all the way to left I get 0 DC and if I go all the way to the right I get ~1.5V!!

Well that narrows down something. I now have 0V DC at all points on the IC except the expected 7 and 11 which both have a stead +/-16V. Unfortunately still getting DC at the outputs. It isn't a stable value and is constantly fluctuating from 0 to 2V. It traced backwards and I have DC at the two parallel caps but prior to them I have 0. Now I am stumped cause I don't know where the DC is coming from.

 

[Gepetto]

Been off the grid for a bit. Work had been hitting me hard the last month. Finally was able to get a little above water and relax this weekend.

Have the WOPL'd 400 running duty in the house powering my KLH Model 5. Super sweet sound!! Been working on the Harmon Kardon Citation 16/17 in the garage. The 16 I have been working on for a while now. Most everything has either been replaced and upgraded on the unit minus the resistors and a couple diodes on the driver boards. Took me a while to get the bias and offset to stabilize but now the unit runs rock solid and it sounds great too. It definitely gives the 400 a run for its money sound wise but definitely not when it comes to pure power.

The 17 is basically what I worked on the most. Opened the unit and gave it a good cleaning and replaced all caps on the power and output board. Splurged a little and got some fancy non-polar mundorf's for the output board. Using this now to feed the 400 in the house and the whole set up sounds pretty awesome. Everything is real crisp, clean and defined. I am really enjoying the music and really feel like I can pick out each instrument.

If anyone is interested in the HK Citation 16/17 overhaul I can post some pics in another thread.

Now that I have my two main amps up and running well I am stuck with just one preamp (HK 17). Decided to try my hand again at the PL 2000 series I. This unit has been the royal thorn in my side. Ended up replacing the two chips located on the adapter thinking I might have fried them in my previous attempts to fix this pre. Well it didn't changed anything. Still getting DC at the outputs. I am getting DC coming off pins 4 and 12 of the IC which shouldn't be happening. Spent forever trying to figure and why as I know now it can't be the IC. Was messing with the treble and bass controls and found that adjusting both left and right bass alters the DC. If I adjust all the way to left I get 0 DC and if I go all the way to the right I get ~1.5V!!

Well that narrows down something. I now have 0V DC at all points on the IC except the expected 7 and 11 which both have a stead +/-16V. Unfortunately still getting DC at the outputs. It isn't a stable value and is constantly fluctuating from 0 to 2V. It traced backwards and I have DC at the two parallel caps but prior to them I have 0. Now I am stumped cause I don't know where the DC is coming from.

Many of the PL preamps rely on screw connections from the PC board to the chassis to work properly. Make sure you have all the intended chassis screws in place and tightened properly. Just something to check. Others have had flakey problems traceable to this.

 

[mjstriker]

Many of the PL preamps rely on screw connections from the PC board to the chassis to work properly. Make sure you have all the intended chassis screws in place and tightened properly. Just something to check. Others have had flakey problems traceable to this.

Should the faceplate be attached to knobs and secured to chassis also? Was thinking maybe they ground in some way just haven't gotten around to doing it

 

[Gepetto]

Should the faceplate be attached to knobs and secured to chassis also? Was thinking maybe they ground in some way just haven't gotten around to doing it

Not totally sure Mike. Just have seen others that were working on these running into problems until all the board screws were in and tight. It is not a good design practice to rely on chassis connections but some companies do that, evidently Phase did. There is a couple of connections in my PL4000 of this sort.

 

[mjstriker]

I checked all the screws and re-attached the faceplate. Didn't change anything. I think the next step is to again see if the output switch is correctly in place. Previously I thought I had swapped one of the rotary knobs as I didn't have any output. I get output now but I am concerned as I get some voltage across the pins which translates into voltage at the RCA inputs. I was wondering if anybody could post some close ups of the rotary discs for the output selector to see if I have things oriented correctly. Need to know which input is currently selected on the photo.

This little bugger is driving me crazy. Can't seem to figure out why I am getting voltage at the output after the caps when there is nothing before and I have appropriate voltage readings from the IC.

 

[laatsch55]

Mike, check some of my older 2000 rebuilds, there are some closeups of that selector. If you don't find any let me know and I'll open one up and take some pics...

 

[mjstriker]

I looked at a few threads and the ones I found didn't have a good shot of the actual rotary part (yellowish plastic part is what I think I can use to orient). I'll double check the threads and any others I might have missed and let you know. Thanks

 

[laatsch55]

K..

 

[mjstriker]

Found a good shot of it. Looks like I have it in correctly. Back to the drawing board

 

[mjstriker]

Trying to figure out a systematic way of approaching this but one I am not understanding how I could get DC voltage on one side of a capacitor when nothing is going in on the other end. Also having the tone control board makes it very difficult to trace where the stray DC is coming.

 

[Gepetto]

Trying to figure out a systematic way of approaching this but one I am not understanding how I could get DC voltage on one side of a capacitor when nothing is going in on the other end. Also having the tone control board makes it very difficult to trace where the stray DC is coming.

Which cap Mike?

 

[mjstriker]

Which cap Mike?

The two back to back 2.2uF in the output. Prior to the "double cap" I have 0 VDC at on the other side of the first I start getting some DC and after the second cap going into the left/right output I get close to 1 VDC that progressively increases to close to 1 VDC then goes down close to 0 VDC and continuously cycles.

 

[Gepetto]

The two back to back 2.2uF in the output. Prior to the "double cap" I have 0 VDC at on the other side of the first I start getting some DC and after the second cap going into the left/right output I get close to 1 VDC that progressively increases to close to 1 VDC then goes down close to 0 VDC and continuously cycles.

Is there a high value resistor, like 220K on the output side of the cap to ground?