Synq SMX-3 mixer, no sound on left output with master 1

[yoritomo]

Good evening all

I have got a Synq SMX-3 professional sound mixer, i can't get any sound from left channel in master 1 output, master 2 is ok.
I could not find any schematics for this devices.

I of course tested reversing the inputs and trying all this inputs and channels with similar result.

If anyone can tell me where to find a schematic, i would be glad.

Thank you by advance.

[yoritomo]

Re: Synq SMX-3 mixer, no sound on left output with master 1

Hello

I could not find anything interesting yet, i am still searching.

[budm]

Re: Synq SMX-3 mixer, no sound on left output with master 1

Any good clear pictures of this device? Since MASTER 2 is OK, the Master 1 circuit is probably the same as Master 2 so you can at least do the comparison testing between the two circuits.

[yoritomo]

Re: Synq SMX-3 mixer, no sound on left output with master 1

Hello

Thanks for your answer, there is some pictures of this device, the VU meter shows signal on left side.

Front panel


top assembly from back side


There we can see the Input Output sockets board , note the big chips i could find everywhere, LC78211 following the datasheet they are a set of bidirectional switches.


In the red circle are the pin of the Master 1 knob , close to each knobs and sliders are small smd op amps.

[yoritomo]

Re: Synq SMX-3 mixer, no sound on left output with master 1

Sorry for my mistake, i posted the preview links of the images, then now are the full sizes.

[budm]

Re: Synq SMX-3 mixer, no sound on left output with master 1

Pictures of the rear panel so I know which ones are for the output and input jacks? Especially the Master one.

[yoritomo]

Re: Synq SMX-3 mixer, no sound on left output with master 1

Hello

Ok then there is the back side. the first pair on left is the master1 output

[budm]

Re: Synq SMX-3 mixer, no sound on left output with master 1

OK, thanks. I will download all the pictures and study them to see how the unit is setup.

[budm]

Re: Synq SMX-3 mixer, no sound on left output with master 1

BTW, does the Trimpot #40 per manual page 11-12 have any effect on the MASTER 1?

[yoritomo]

Re: Synq SMX-3 mixer, no sound on left output with master 1

Hello

Finally I could find the faulty transistor, it was on the small brown board we can see on above picture, marking code is WT as i could find it is a 2SK322 which does not have any cross reference, this small smd at my providers, ASWO is about 22€ without VAT !? do you know any good replacement for this one ?