10 years ago, I bought a complete set of Pioneer Hi Fi system (one
piece which comes as an add on a turntable PL-Z91. This turntable has
no separate power supply but takes its power from the HiFi system
throught a special plug. It is written on the turntable that the power
which is getting from the HiFi system is DC IN 12V---.
I changed the HiFi system with a newer model which is coming without
this power support for the turntable. When I tried to connect the
turntable to out source of the same voltage (adapter of 12V), the
turntable does not function at all.
I tried to measure the voltage coming in from the adapter after
connection of the adapter, it is only 3-4v.
I don't know what is wrong? and how can I make the turntable function
again?. which electricity source should I use?

---

Request for Question Clarification by haversian-ga on 14 Oct 2002 13:39 PDT

Do you still have access to the old HiFi system?

If not, are you sure you have the polarity right?

Are there any other stickers on the turntable?  Does it list power
consumption, for example?

If you're sure, do you have or can you obtain a bench power supply? 
Not a wall-wart transformer, but something that you've got some
control over?  A rental company might even have something that you
could use.  If you can get your hands on one, plug it in, set it to
12V, and slowly turn up the amperage.  Be careful the unit is not off
or you might burn it out before you get any results.  Also, be sure it
is going to actually *do* something to indicate when it has enough
power - is there a power LED or some such?

I'm not sure if I'm correctly understanding your situation, so correct
me if my assumptions are wrong. If you are attempting to use a
seperate 12-volt power supply such as would be purchased at an
electonics store (the 'wall-wart' type where the transformer plugs
directly into the outlet) and the voltage is dropping to 3-4 volts
when you plug it into the turntable, this implies that the power
supply is not capable of producing sufficient current (or 'Amperage')
for the turntable. If this might be the case, check the turntable to
see if it also supplies you with a current requirement along with the
voltage requirement; for something of that nature, i would guess this
would be higher than what most power supplies of the type described
can produce, which is usually less than 1 Amp.

Is this at all related to what you were asking? :)

yawfle-ga

Hi, 

From your question:
>>I tried to measure the voltage coming in from the adapter after
connection of the adapter, it is only 3-4v.>>

I would like to know what you actually did. How did you measure the
voltage, "after connection of the adapter" ?

warm regards
vinods