Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5

Stereo MPX Decoder for old Sony
#16

I was thinking the same. There are many +12 Ground to -12 polarity converters in the market (mainly for old cars) but not one like that. I would even take +12 to-12 converter.

I thought this Sanyo chip is probably not necessarily positive ground. I can see the legs where the L and R channels are coming out. I can bypass the headphone amp they have built in. But what can I use for a ground? Would the chip's negative supply be the new negative ground. I got stuck there.

In a Yamaha receiver, the same chip is used with a negative ground. I have schematic for it but could not find one for the Sanyo.
#17

Hello Toptip,
First all what is the IC part no . and what is the sony model number ?

Sincerely Richard
#18

The chip is Sanyo A3311. It is obsolete, I could not find a data sheet for it. All my information is from a Yamaha CR500 receiver where it was also used.

The Sony? If you mean Sanyo, it is called RB9000. There are two versions of it, with and without a headphone permanently attached.
#19

Toptip,
Because Sanyo did make a LA 3361 because most sanyo IC chips had LA I used to be a factory Warranty and service for Sanyo/Fisher .

Sincerely Richard
#20

Yes, in fact when I was searching for the A3311, I came across LA3361. It looked quite different. I will send you the schematic of this chip from the Yamaha manual.
#21

Is there a way to load an image?
#22

And you are right. While chip says A3311 on it, elsewhere it does come up as LA3311:

https://icompplus.com/en/others/LA3311
#23

Hi,

This is the schematic showing the chip (which I highlighted in yellow, as I found it confusing).

Is this chip made for a positive ground or is that how Sanyo has used it? 

If possible, I would like to change it to negative ground.

All the best


Attached Files Image(s)
   
#24

The quick answer is "not possible". The VCC to the circuit is negative voltage, the filter caps positives are connected to gnd and the transistors are NPN.
#25

This is the same chip, used with negative ground. I suppose I could do enough surgery to change things from positive to negative but might be easier to build a new circuitboard. I wish I could find the original datasheet with a simple schematic.


Attached Files Image(s)
   




Users browsing this thread: 2 Guest(s)
[-]
Recent Posts
My last cabinet for this year
They are a nice looking radio, Stromberg. I have a small tabletop octagon-dial one. It sounds surprisingly nice. And t...morzh — 09:40 PM
Philco 41-608 changer coupler
Different years but the same idea.morzh — 09:38 PM
My last cabinet for this year
That’s a beauty! :thumbup:klondike98 — 09:24 PM
Philco 41-608 changer coupler
Hi Morzh, I've searched using Mondial as the user name with various keywords such as 'coupler', 'motor', 'idler', 'p...alangard — 08:31 PM
Philco 16B Parts
I think the chassis is painted.morzh — 08:13 PM
Philco 38-2 Automatic Tuning
Honestrly, the original is quite acceptable and, it seems to me, can be cleaned.morzh — 08:11 PM
Philco 41-608 changer coupler
Mondial left a thread about remanufacturing thois type coupler.morzh — 08:09 PM
IF can wire size and Rubber mounts?
Are you talking about rewinding or rewiring? For rewiring, meaning runnin wires to the coil from other components, the ...morzh — 08:08 PM
12' Philco
I wonder who would be able to "no stoop" with this one.morzh — 08:05 PM
IF can wire size and Rubber mounts?
Hello PHORUM members, I am still working on restoration of my PHILCO 37-640.  I want to start with rewiring the IF ca...georgetownjohn — 06:32 PM

[-]
Who's Online
There are currently no members online.

>