Will this mod work for Panasonic FS-A1WX?

Guardian (3609)

02-07-2016, 22:12

As there was a discussion about replacing a broken transformer in the TurboR ST earlier, I wonder will the same replacement transformer and wiring work for the Panasonic FS-A1WX:

https://www.msxinfo.net/2014/04/29/panasonic-turbo-r-fs-a1st...

The cases are quite similar, the WX probably does not consume more power than ST. Has anyone done this modification?

By Pentarou

Hero (524)

03-07-2016, 13:00

It's not the same: the A1ST has just one ~15V supply while the A1WX has ~12V and an additional wire to generate +/- 12V.

By Wierzbowsky

Guardian (3609)

03-07-2016, 13:23

Pentarou wrote:

It's not the same: the A1ST has just one ~15V supply while the A1WX has ~12V and an additional wire to generate +/- 12V.

As far as I see the transformer on ST outputs ~12v AC to the board from 2 different coils. The DC conversion is done on the board to +/-12v and +5v. I doubt that on WX this is done in a different way. The transformers and wiring looks the same. I will disassemble my WX once the transformers arrive...

By Pentarou

Hero (524)

03-07-2016, 13:59

Alexey wrote:

I doubt that on WX this is done in a different way.

It's different

Alexey wrote:

The transformers and wiring looks the same.

The A1 transformer connector has 3 wires while the WX has 4 wires. It has an additional coil that is used (on the pcb) to generate the +12V and -12V.

Why do you want to replace the transformer when you can use a small switching power supply?

By Wierzbowsky

Guardian (3609)

03-07-2016, 15:06

I see. I wonder whether I can use the same coil for +/-12v and the other coil for +5v. The -12v is used mostly on the cartridge connector and maybe on the amplifier. I don't have the schematics at hand to check.

By Wierzbowsky

Guardian (3609)

04-07-2016, 00:02

So with some adjustments on the board this should work...

I wonder if there's an easier way...

By Wierzbowsky

Guardian (3609)

04-07-2016, 02:47

So rewiring will require 3 cuts and 4 wires:

By Wierzbowsky

Guardian (3609)

04-07-2016, 12:15

I talked to our group's electronics engineer and he told me that the 3 pin transformer will work if connected to this board. One of the transformer's output can be connected to both pins 3 and 4 of the board. I will try this once my transformer is here.

By -Neo-

Champion (396)

05-07-2016, 00:12

But the transformer we are talking about seems to be a 4 pin transformer if you look at the picture at the conrad site. RIght?

As I also have a WX I am very interested to see whether you get this to work with the WX too.

By Wierzbowsky

Guardian (3609)

05-07-2016, 15:55

-Neo- wrote:

But the transformer we are talking about seems to be a 4 pin transformer if you look at the picture at the conrad site. RIght?
As I also have a WX I am very interested to see whether you get this to work with the WX too.

No the transformer has 3 outputs in reality. Conrad just used a generic image. Out electronics guru says that it should work fine, but needs some attention in the beginning. I am going to measure the temperature of the transformer as well as critical elements in the DC converter circuit. The voltage limits of all converter components on the board allow this transformer to work without problems. But some components may be heated a bit more than with the old transformer.

By meits

Scribe (6544)

05-07-2016, 16:43

Alexey wrote:

No the transformer has 3 outputs in reality. Conrad just used a generic image.

Ah that explains why I have three pins