Check idle current on PA 7 Nakamichi

[Laurent Lafran]

Hello to every sound lovers,
i'm a new happy owner of a Nakamichi PA7. I heard that sometime idle current are increasing and can make damage. So, before bringing my amplifier to a technical station i thought that i could have an idea by measuring the amplifier consuption on the main cable.
Do you think it's a good idea and what could be the consuption of the pa7 WITH 0volt on the input ?
Thanks,
Laurent.

 

[analog_sa]

Do you think it's a good idea

Not very good. One channel may be up, while the other is down and the total consumption is still normal. Just open it and measure the voltage drops on the emitter resistors. If it's similar to the Threshold amps you would expect around 100mA per transistor or maybe someone can provide accurate values.

Here is the relevant thread

 

[Nelson Pass]

Put your hands on the heat sinks. If you can hold them there for
10 seconds or so, then it's just right.

 

[MadMutt]

To suit PA7 and PA7e.
From service manual.
Enjoy 😉

PS, this 100k/1000pixels limit is really starting to wee wee me off big time..........

 

[jiky657]

@MadMutt
Would it be possible to get a copy of the PA7e service manual?
My emailaddress is me@stairweb.de
Thanks a lot!
Regards
Markus

 

[Laurent Lafran]

Thanks to everybody.
My PA7 is now working with Rega Planar 3/RB 300 + DL103, Préamp Naka CA5E, Ditton 66 monitor rewired and Terminator 2 cable for loudspeakers.
Any advice ?
Best regards to all,
Laurent.