Phase Linear 700 series 2 questions

OZ of da trap

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#21
No, the transistors bolted to the outside of the heatsinks. If an output is blown, often q7, q10on the driver board are also blown.
Ok I find looking at the diagrams on age 9 the 700/700b the 700 diagrams shows q07 and g10 but this diagram is for either of the two. So mine is a 700 II series and I think the diagram 2-7 shows the same location for these except as q107 and q110, right?
 

laatsch55

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#22
I don't have a Ser II schematic in front of me. Read the section on testing the outputs...
 

OZ of da trap

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#23
OK, my eyes are telling me to close for tonight. Let me review the manual and the step by step method you are talking about. Sounds like what I have to do a lot of with the electronics on outboard motors and auto engines. In the military in the 60's we had to do all kinds of checks and inspections on circuits with pre-flight booklets / checks on the flight line and in the hanger
 

laatsch55

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#24
Yeah, from the description you gave, you probably have more than one output shorted. The service manual is well written on that procedure...
 

OZ of da trap

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#28
It may be better if you get the Series II manual.
If you can't find it, PM me with your email and I'll send it to you.
That would be good. Looks like you are a JBL fan. I am acquiring some 15's this year. Also I have a stray cat that visits me daily ...looks like your cat in your pic
 

pennysdad

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#29
That would be good. Looks like you are a JBL fan. I am acquiring some 15's this year. Also I have a stray cat that visits me daily ...looks like your cat in your pic
The problem with JBL's is that they sound their best just before they blow up. You have to go there so you know exactly where that is. Then, after you get 'em fixed, you know just where not to go and then they'll be sounding their best and will last forever, [or until your amp goes DC].
Love my JBL's. I used 'em at work, so only fitting to use them at home. It's a Buddhist thing....
My late Kitty, [Penny RIP] looked just like that. She was always filing her claws...
 

AngrySailor

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#33
Pop them thin covers off between the cooling fins to expose the output trannies. You may see evidence of the magic smoke having left one or more...
 

pennysdad

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#34
If you're intending to turn this into a serious project, I think maybe this might need to be a new thread.
See what Lee thinks.

Ohh, I just realised it IS!!!!!! Oh sh*t! Sorry....
 

OZ of da trap

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#37
The series II amps are about the easiest amp to troubleshoot because they are so simple. The service manual tells you how to test all of the outputs in circuit. No need to pull them. Then you test all of the transistors and diodes on the board. Keep in mind the manual was written when all we had were analog meters such as the Simpson 260. Today everybody uses a digital meter. Regardless, a shorted transistor junction or shorted diode reads zero ohms.

For some reason , R101, 7.5K/2W likes to fail. They never show signs of heat stress. They drift then open.

There is no question doing all of the W/O mods is the long term solution. However it's nice to know the amp was working before starting the rebuild.
Thats kinda my point to know IF the amp works and or trouble shoot the process to arrive at a point to get it working or to stop and move on. This amp is something back in the 70's that my cousin and I wanted but cost was an issue and at the time we both had good stereo systems and still playing vinyls at that time. But just needed to know how they would sound. I bought a Sansui later in the early 80's replacing a kit built Eico ST 40 tube amp. Thanks
 

mlucitt

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#38
I see at least five replaced resistors and the one cracked 10 Ohm resistor (looks like R116). You have an amplifier that has seen some serious re-work. Nothing against your abilities, it is a matter of experience with these amplifiers, you need some help.
The options are: 1) to get a technician to your place (not likely), 2) get the amplifier to a technician, or 3) to try and tackle it yourself. Many here started out by taking the third option. Be careful, there is no turning back when you bite the WOPL bullet.
You have $0 invested, why not spend some White Oak dollars and have a very nice amplifier that you can pass on to your kids, and then the grandkids...
Buy the parts and jump in or send the amplifier and a blank check to one of the skilled technicians on this forum. Your choice.
 

OZ of da trap

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#39
I see at least five replaced resistors and the one cracked 10 Ohm resistor (looks like R116). You have an amplifier that has seen some serious re-work. Nothing against your abilities, it is a matter of experience with these amplifiers, you need some help.
The options are: 1) to get a technician to your place (not likely), 2) get the amplifier to a technician, or 3) to try and tackle it yourself. Many here started out by taking the third option. Be careful, there is no turning back when you bite the WOPL bullet.
You have $0 invested, why not spend some White Oak dollars and have a very nice amplifier that you can pass on to your kids, and then the grandkids...
Buy the parts and jump in or send the amplifier and a blank check to one of the skilled technicians on this forum. Your choice.
I'm sure I can do the work.soldering is one of my specialties.....patience and perfection are in my DNA. Its just a matter of my time, cost, outcome. I have many hobbies that presently involve in resto - moding street hi performance cars, performance engine building, speaker system enclosures/crossovers/recone , designing hi voltage / low voltage electrical control systems , welding, wood working just to name a few. I am
presently into a 67 nova super sport resto, refurbishing a Suzuki 140 hp outboard, and honey do items. My time is limited to when and what I want to do. The PL 700 may or not be a project in the near future...I will see
Thanks
 

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AngrySailor

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#40
I'm sure I can do the work.soldering is one of my specialties.....patience and perfection are in my DNA. Its just a matter of my time, cost, outcome. I have many hobbies that presently involve in resto - moding street hi performance cars, performance engine building, speaker system enclosures/crossovers/recone , designing hi voltage / low voltage electrical control systems , welding, wood working just to name a few. I am
presently into a 67 nova super sport resto, refurbishing a Suzuki 140 hp outboard, and honey do items. My time is limited to when and what I want to do. The PL 700 may or not be a project in the near future...I will see
Thanks
NICE... I’ve got a pretty original 67 Biscayne, 4 door, 250ci, three on the tree that I bomb around in the summer with. It’s getting a little ragged but still original paint and interior. Here’s a big block I’m working on putting .903 lifters in, she’s 489ci and Hilborn mechanically injected. That goes in my ~70-71ish 19’ V-Drive Hondo flat bottom drag boat.
 

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