Phase Linear 4000 advice needed

[maxhifi]

Hi,

I haven't posted here for a while, but does anyone have a schematic for a
Phase Linear 4000, or perhaps some knowledge of how to fix one? It's a lot
more complex than one would expect a preamp to be! The autocorrelator
function has stopped workign normally, and makes a loud rushing sound!

[Trevor Wilson]

"maxhifi" > wrote in message
news:NhyXh.125026$aG1.81693@pd7urf3no...
> Hi,
>
> I haven't posted here for a while, but does anyone have a schematic for a
> Phase Linear 4000, or perhaps some knowledge of how to fix one? It's a lot
> more complex than one would expect a preamp to be! The autocorrelator
> function has stopped workign normally, and makes a loud rushing sound!

**Before you do anything, remove all the daughter cards and carefully clean
each and every connector (plug and socket). It is one Hell of a big job and,
IMO, not worth the effort, as the 4000 is a piece of crap. After you clean
the connectors, you will have probably solved the underlying problem. Dump
it and buy a decent preamp. The autocorrellator was a wank anyway.


--
Trevor Wilson
www.rageaudio.com.au



--
Posted via a free Usenet account from http://www.teranews.com

[Eeyore]

Trevor Wilson wrote:

> "maxhifi" > wrote in message
>
> > Hi,
> >
> > I haven't posted here for a while, but does anyone have a schematic for a
> > Phase Linear 4000, or perhaps some knowledge of how to fix one? It's a lot
> > more complex than one would expect a preamp to be! The autocorrelator
> > function has stopped workign normally, and makes a loud rushing sound!
>
> **Before you do anything, remove all the daughter cards and carefully clean
> each and every connector (plug and socket). It is one Hell of a big job and,
> IMO, not worth the effort, as the 4000 is a piece of crap. After you clean
> the connectors, you will have probably solved the underlying problem. Dump
> it and buy a decent preamp. The autocorrellator was a wank anyway.

What's the obsession with obsolete antiques anyway ?

One might also want to replace all the electrolytic caps too.

Graham

[Trevor Wilson]

"Eeyore" > wrote in message
...
>
>
> Trevor Wilson wrote:
>
>> "maxhifi" > wrote in message
>>
>> > Hi,
>> >
>> > I haven't posted here for a while, but does anyone have a schematic for
>> > a
>> > Phase Linear 4000, or perhaps some knowledge of how to fix one? It's a
>> > lot
>> > more complex than one would expect a preamp to be! The autocorrelator
>> > function has stopped workign normally, and makes a loud rushing sound!
>>
>> **Before you do anything, remove all the daughter cards and carefully
>> clean
>> each and every connector (plug and socket). It is one Hell of a big job
>> and,
>> IMO, not worth the effort, as the 4000 is a piece of crap. After you
>> clean
>> the connectors, you will have probably solved the underlying problem.
>> Dump
>> it and buy a decent preamp. The autocorrellator was a wank anyway.
>
> What's the obsession with obsolete antiques anyway ?

**Who knows? When it was new, the 4000 was crap. 30 years on, it is old
crap.

>
> One might also want to replace all the electrolytic caps too.

**Indeed, but it will probably be the connectors that are causing the
problem. There's a lot of them and that cheapskate Bob Carver didn't bother
with gold plating anything.


--
Trevor Wilson
www.rageaudio.com.au



--
Posted via a free Usenet account from http://www.teranews.com

[maxhifi]

"Trevor Wilson" > wrote in message
.. .
>
> "Eeyore" > wrote in message
> ...
>>
>>
>> Trevor Wilson wrote:
>>
>>> "maxhifi" > wrote in message
>>>
>>> > Hi,
>>> >
>>> > I haven't posted here for a while, but does anyone have a schematic
>>> > for a
>>> > Phase Linear 4000, or perhaps some knowledge of how to fix one? It's a
>>> > lot
>>> > more complex than one would expect a preamp to be! The autocorrelator
>>> > function has stopped workign normally, and makes a loud rushing sound!
>>>
>>> **Before you do anything, remove all the daughter cards and carefully
>>> clean
>>> each and every connector (plug and socket). It is one Hell of a big job
>>> and,
>>> IMO, not worth the effort, as the 4000 is a piece of crap. After you
>>> clean
>>> the connectors, you will have probably solved the underlying problem.
>>> Dump
>>> it and buy a decent preamp. The autocorrellator was a wank anyway.
>>
>> What's the obsession with obsolete antiques anyway ?
>
> **Who knows? When it was new, the 4000 was crap. 30 years on, it is old
> crap.
>
>>
>> One might also want to replace all the electrolytic caps too.
>
> **Indeed, but it will probably be the connectors that are causing the
> problem. There's a lot of them and that cheapskate Bob Carver didn't
> bother with gold plating anything.
>
>
> --
> Trevor Wilson
> www.rageaudio.com.au
>
>
>
> --
> Posted via a free Usenet account from http://www.teranews.com
>

Thanks guys.... I took it apart, and cleaned everything - traced problem to
a bad electrolytic cap. I can't believe how lucky I was finding it, as it
was the first one I replaced, and this unit has dozens of them. I intend to
replace the rest of them as maintenance, but it will have to wait a little
bit.

Why am I fixing it?? It's not really mine, I'm doing it as a favour for a
friend. In my system it sounds alright. A touch sharp sounding, but not bad.
The correlator works reasonably well, it does tend to get rid of tape hiss.

Not one of the connectors was even slightly corroded - the preamp is in
really nice shape. I fixed it for the original owner, who has never felt a
need to change it for something else.