I just found the above-mentioned amp in my store room. It actually looks
like quite a nice old thing. A new (Alps) volume pot and it runs a
treat. Fairly primitive output devices (MJ802/MJ4502), but, given the
age, it's a reasonable choice. Does anyone have any information on this amp?



--
Trevor Wilson www.rageaudio.com.au

"Trevor Wilson"

I just found the above-mentioned amp in my store room. It actually
looks like quite a nice old thing. A new (Alps) volume pot and it runs
a treat. Fairly primitive output devices (MJ802/MJ4502),


** Motorola's MJ802 / MJ4502 complementary pair dates from the early
1970s - so TW thinks that makes them "primitive".

I used a pile of them both for building and repairing amplifiers through the
70s - cos they were rugged and versatile enough to replace most of the Asian
2SAxxx and 2SDxxx numbered types I came across ( particularly in various SAE
models) but could not buy anywhere in Australia.

Most examples exceeded published specs in relation to Vce and Hfe (beta) -
the latter being high even at low currents - one MJ4502 I tested showed a
Hfe of 450 at an Ic of 1mA - just like a BC109 !!

Some here may have seen Doug Self's "Blameless Amplifier" design published
in 1993 in Wireless World magazine. Doug used the very same Motorola pair to
get vanishingly low THD figures from a deceptively simple looking design.

Those who tried to replicate his results fell short cos original spec MJ802s
and MJ4502s were no longer available.


..... Phil

Sounded a bit bright to me, but some like the clinical sound, and it may,
given its age merely be a bit affected by speaker reactance.
they were very reliable, obviously made capacitors better in those days than
they do now.
brian

--
From the Sofa of Brian Gaff Reply address is active
"Trevor Wilson" wrote in message
...
I just found the above-mentioned amp in my store room. It actually looks
like quite a nice old thing. A new (Alps) volume pot and it runs a treat.
Fairly primitive output devices (MJ802/MJ4502), but, given the age, it's a
reasonable choice. Does anyone have any information on this amp?



--
Trevor Wilson www.rageaudio.com.au

"Brian Gaff = top posting pommy idiot "


Sounded a bit bright to me,


** You sound VERY dull to me.


but some like the clinical sound,


** You need to visit a clinic - for psychiatric outpatients and pommy
****heads.


and it may, given its age merely be a bit affected by speaker reactance.


** So what are YOU being affected by - eh ??

The absence of anti-psychotic drugs OR the presence of illegal ones ??


they were very reliable, obviously made capacitors better in those days
than they do now.


** Massive pile of stinking bull**** - on both counts.





.... Phil

In article , Phil Allison
scribeth thus

"Brian Gaff = top posting pommy idiot "



Phil....


Brain top posts for a very good reason which I thought you know about
and because he does that it doesn't make him a "pommy" idiot...

thanks...

--
Tony Sayer

On Mon, 13 Jan 2014 22:56:48 +1100, Phil Allison wrote:

"Brian Gaff = top posting pommy idiot "


Sounded a bit bright to me,


** You sound VERY dull to me.


but some like the clinical sound,


** You need to visit a clinic - for psychiatric outpatients and pommy
****heads.


and it may, given its age merely be a bit affected by speaker
reactance.


** So what are YOU being affected by - eh ??

The absence of anti-psychotic drugs OR the presence of illegal ones
??


they were very reliable, obviously made capacitors better in those days
than they do now.


** Massive pile of stinking bull**** - on both counts.





... Phil


Oh dear, having a bad day again Phil? Won't they talk to you on RAT?

I hope you enjoyed that little rant at Brian. He'll have fun scrolling
through it on his screen reader - he can't actually see it. That's why he
top posts too.

Now toddle off and sit in the dark for a bit to calm down.

On 13/01/2014 8:38 PM, Brian Gaff wrote:
Sounded a bit bright to me, but some like the clinical sound, and it may,
given its age merely be a bit affected by speaker reactance.
they were very reliable, obviously made capacitors better in those days than
they do now.
brian


**Thanks for the info. I was hoping for a reference to some advertising
literature. It is a nicely made product. The cable lacing takes me back
a bit.

--
Trevor Wilson www.rageaudio.com.au

"tony sayer"


** **** off Tony - you colossal moron.





..... Phil

"Trevor Wilson" wrote in message
...
I just found the above-mentioned amp in my store room. It actually looks
like quite a nice old thing. A new (Alps) volume pot and it runs a treat.
Fairly primitive output devices (MJ802/MJ4502), but, given the age, it's a
reasonable choice. Does anyone have any information on this amp?


There is some info here on the P50, P60, P80, P100 and P110 including
schematics and owners manuals, may be of some use:

http://www.hifiengine.com/library/Cambridge-Audio.shtml


David

In article , Phil Allison
scribeth thus

"tony sayer"


** **** off Tony - you colossal moron.


That comment speaks volumes about your sad self.


But then again when has it been any different?........






.... Phil





--
Tony Sayer