Sony PCM-7050
Vintage wrote:
I got hold of a Sony PCM 7050 dat recorder in good condition.
The only thing is that sometimes the recorder does not power up.
I have been measurning the voltages on the power pc-board in the unit, under
the power transformer, and these are OK.
Therefore I now have the idea that the switching power supply is the cause
of the problem and regularly does not "boot up".
More and more it points in that direction.
It simply does not "start"...
There are times that the PCM-7050 powers up normally and can be switched off
and on several times without any problem.
When the PCM has been switched off for about half an hour it does not power
up anymore.
Does anybody have had similar problems and/or repaired the switched power
supply at the back of the unit ?
Are there parts in such a psu that must be checked first, I mean are there
components that regularly fail in this psu ??
There are no schematic diagrams of the psu in the Sony manual, because Sony
used a psu from a third party supplier and only gives the input and output
connector pin configurations.
The PCM is powered by 240Volts AC (Europe) and that is what I measure on one
of the small white psu connectors.
On the other small white psu connector I measure approx 120 Volts AC. And
of course no output voltages on the larger red connector.
The psu is still available from Sony Professional, but the price is quite
high.
Somebody having a spare for me ?
Sending the PCM to Sony service is quite complicated here and apart from
that also quite expensive.
Richard,
the Netherlands.
Check electrolytic capacitors in the PSU - look for doming or leakage.
Guy
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