Can I make two inputs from one??

[Jazz_3_4_5]

Gents, & Ladies if that be the case....May I indulge my curiosity for a moment?

I have recently acquired a Japanese made Audio Mixer. that has seen some abuse. and as a learning experience,
I wish to bring it back into the fold for home use.

The Power supply is missing, and the Headphone Jack was smashed. I have found a replacement Headphone Jack, and will replace that when it arrives. In the meantime I have searched out the schematic, and this unit has a 3 legged power supply... two Positive legs and a Negative leg.

I am wondering if it is possible to use a 2 wire wall wart, and put a jumper in place of the second positive,
as shown in the schematic I included.
My thinking is that since the mixer, only draws 500mA maximum, a jumper should cover this situation.
Since I have no need for the Phantom power, as all my Mic's are Dynamic, & not Condenser types,
I'll disable it, by removing R101 A thru 104 A, and the 47 uF cap.

If you disagree with my diagnosis, please elaborate, and Possibly offer me an alternative.
I'm 80 yrs old, and trying to keep my mind as sharp as Possible, as I plan to keep using it
for at least another 30 years, and hopefully more!

You have my gratitude!

 

[Jazz_3_4_5]

strange! I can reply here but not to last post

 

[Jazz_3_4_5]

Don't have priveliges (SOLVED)
I had two instances of the same page open.
\ when I closed one the message disappeared.

 

[samlevy0515]

Respect for tackling this project at 80! ️ Your plan sounds logical, but I'd be cautious about jumpering the dual positive rails—some mixers use them for separate analog/digital sections. Maybe test with a bench PSU first?

 

[Jazz_3_4_5]

Yes, Nigel.
The project is on hold for a while.(Disbursal's being greater than receivables...)
{Old age is bloody difficult on the dole} Having already ordered the first
transformer prior to joining here.
I don't intend trying it though, and will wait until my receivables increase to a point that
I can order the Correct Xformer from RS.

The Mixer is not crucial to me as I do have a working 16 channel Mackie mixer, and another 4 channel Behringer mixer. All from my days past, as a local "Rock Star"......The last band I had was in 2017, and even then It was difficult to haul around a Hammond M3, and a Leslie. Now I just play for my own enjoyment, using a Roland G-800 workstation, connected to a laptop with MIDI, (Musical Instrument Digital Interface), and slew of virtual instruments. Not too many musicians my age, and genre around here, and I'm not about to drive 2 hours each way for an hour's "Jam session". I enjoy playing 40 - 50 year old music
that younger musicians find "ANCIENT". But as you know those songs have meaning and memories.

Jazz

 

[Jazz_3_4_5]

Respect for tackling this project at 80! ️ Your plan sounds logical, but I'd be cautious about jumpering the dual positive rails—some mixers use them for separate analog/digital sections. Maybe test with a bench PSU first?

Thank You !! And thanks for your advise.
Nigel, advised a different approach, and I'll follow that, as soon as receivables allow....

Jazz

 

[rjenkinsgb]

I enjoy playing 40 - 50 year old music

Still the best musical era, in my opinion!

 

[Nigel Goodwin]

Still the best musical era, in my opinion!

Can't beat 60's and 70's music!

 

[Jazz_3_4_5]

Can't beat 60's and 70's music!

You've got that right..
But the funny thing.......

I can't imagine Paul McCartney being same age as me!!
Strange when old people are your age!

 

[Jazz_3_4_5]

I can't imagine Paul McCartney being same age as me!!

Oops!
Correction for all the McCartney fans .
I'm not as old as he is (Phew!) Paul was 83 in 2025.
I have three tears to catch up... Chronologically anyway.....