I picked up a mint condition Pioneer PL-930 direct drive turntable today
(bric-a-brac day at Milton Keynes market), and discover that it's fitted
with a moving coil pickup cartridge, an MC3, with I guess a pre-amp buried
in the deck.

Can anyone advise what voltage and polarity is required for the pre-amp?
Alongside the red and white phono type audio leads, there's a 3.5mm mono
plug (2 pole), and I assume that this is for the pre-amp's power supply.

On the web, I've found belts listed for this turntable. Can't see any form
of belt when I take off the turntable platter, and I thought direct drive
didn't need belts. Could the "fully automatic" pick-up arm require one?

Many thanks

--
M Stewart
Milton Keynes, UK



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

On Thu, 2 Nov 2006 18:46:20 -0000, "Malcolm Stewart"
wrote:

I picked up a mint condition Pioneer PL-930 direct drive turntable today
(bric-a-brac day at Milton Keynes market), and discover that it's fitted
with a moving coil pickup cartridge, an MC3, with I guess a pre-amp buried
in the deck.

Can anyone advise what voltage and polarity is required for the pre-amp?
Alongside the red and white phono type audio leads, there's a 3.5mm mono
plug (2 pole), and I assume that this is for the pre-amp's power supply.

On the web, I've found belts listed for this turntable. Can't see any form
of belt when I take off the turntable platter, and I thought direct drive
didn't need belts. Could the "fully automatic" pick-up arm require one?


It would be most unusual for a turntable unit to incorporate a preamp,
though I couldn't swear it never happened. There were some strange
designs - a section of the audiophile market was then, as now,
prepared to accept almost anything as long as it was sufficiently
esoteric and sufficiently expensive :-)

Back in the day, quite ordinary domestic amplifiers accepted both
moving-coil and moving-magnet pickups. Though there was a thriving
market in boutique alternatives.

"Laurence Payne" lpayne1NOSPAM@dslDOTpipexDOTcom wrote in message
...


It would be most unusual for a turntable unit to incorporate a preamp,
though I couldn't swear it never happened. There were some strange
designs - a section of the audiophile market was then, as now,
prepared to accept almost anything as long as it was sufficiently
esoteric and sufficiently expensive :-)

Back in the day, quite ordinary domestic amplifiers accepted both
moving-coil and moving-magnet pickups. Though there was a thriving
market in boutique alternatives.

Thanks for your comments.

I've now had the unit running with the audio leads feeding a headphone
amplifier. Output was low (too low with my deaf ears to decide whether the
o/p was "level" or whether there was a treble rise (as per uncompensated
RIAA), and I decided to check whether there was any voltage on the 3.5mm
plug. There was - it varied from around 1V to ~ -0.5V on the centre pin of
the plug. The variations seemed to depend on the position of the PU arm,
and what state the deck was in. Perhaps a control/info signal to some
Pioneer Amp.?

--
M Stewart
Milton Keynes, UK



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

"Malcolm Stewart" wrote in
message .. .

I've now had the unit running with the audio leads feeding a headphone
amplifier. Output was low (too low with my deaf ears to decide whether
the o/p was "level" or whether there was a treble rise (as per
uncompensated RIAA), and I decided to check whether there was any voltage
on the 3.5mm plug. There was - it varied from around 1V to ~ -0.5V on the
centre pin of the plug. The variations seemed to depend on the position
of the PU arm, and what state the deck was in. Perhaps a control/info
signal to some Pioneer Amp.?


I've now got the unit working straight into the phono i/p of my "hi-fi"
amplifier, and whilst the level is down say ~ 6-10dB compared to my Shure
moving magnet / vari-reluctance M75ED, it sounds fairly well balanced, so
there must be a pre-amplifer somewhere.
(Cheap Sony turntables certainly incorporate a pre-amp as the o/p can be fed
straight into a flat amp i/p.)

Been into audio since the mid 1950s and this is the first time I've owned an
MC cartridge!
--
M Stewart
Milton Keynes, UK



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

In article ,
Malcolm Stewart wrote:
I've now got the unit working straight into the phono i/p of my "hi-fi"
amplifier, and whilst the level is down say ~ 6-10dB compared to my
Shure moving magnet / vari-reluctance M75ED, it sounds fairly well
balanced, so there must be a pre-amplifer somewhere.

Why? Some high output MC carts work straight into the phono input.

--
*Thank you. We're all refreshed and challenged by your unique point of view

Dave Plowman London SW
To e-mail, change noise into sound.

On Thu, 2 Nov 2006 19:52:56 -0000, "Malcolm Stewart"
wrote:

I've now got the unit working straight into the phono i/p of my "hi-fi"
amplifier, and whilst the level is down say ~ 6-10dB compared to my Shure
moving magnet / vari-reluctance M75ED, it sounds fairly well balanced, so
there must be a pre-amplifer somewhere.


Not necessarily.

Laurence Payne wrote:

It would be most unusual for a turntable unit to incorporate a preamp,
though I couldn't swear it never happened.

Project do one of their turntables with phono stage built into deck

On Thu, 02 Nov 2006 20:31:15 GMT, "Dave xxxx" wrote:

It would be most unusual for a turntable unit to incorporate a preamp,
though I couldn't swear it never happened.

Project do one of their turntables with phono stage built into deck

I meant in the days when vinyl was mainstream and amps had phono
inputs.