hifi engine

BSR SA-3X tech details ?

I have one of these nice little spectrum analysers, but [hesitates, coughs] some years ago I blew the fuse (on PCB under the switch) and the power transformer primary. Naturally I did this by stupidly connecting it to the local 240V AC instead of the 115V it expected. [Yes, it had had a 115V supply, but I was re-cabling everything...]

Does anyone have a BSR SA-3X working, or at least with an intact power transformer? Or a schematic? If I can find out the secondary voltages I can provide those and so find what else was damaged. There is no visible sign of overheated components.

Hopefully, Brian.

Re: BSR SA-3X tech details ?

I just bought one of these on eBay; should be here by Jun 8. I will get the info you need when it arrives.

Re: BSR SA-3X tech details ?

Great, Johnny.

The secondary windings on mine are red - (centre-tap) black - red

and blue - (c-t) yellow - blue.

The mains supply is fairly well shielded from fingers except on the switch circuit board. Take care.

Cheers and thanks

Re: BSR SA-3X tech details ?

Voltages are: Red 36 volts AC center tap (black) at 18 volts; Blue 3 volts AC center tap (yellow) at 1.5 volts. The 3 volts may sound odd but it was used for florescent displays; don't go higher with this voltage.
I don't know where you live, but Mouser in the US may have a transformer that will work.

Re: BSR SA-3X tech details ?

You have done well. Your spectrum analyzer has arrived early and obviously it is working. Also you have given me information that I would never have guessed without a lot of circuit tracing (and taking the unit apart enough to trace the circuit would be hard work). Many thanks.

I will let you know how I go, first with supplying the two voltages and looking for other over-voltage damage. A transformer can come later. Meanwhile, I think I still have a user's manual although it doesn't say much except how to cable the unit into a system. Do you have one?

Re: BSR SA-3X tech details ?

Yes, I have the user's manual.