sony betamax modulator. - UK Vintage Radio Repair and Restoration Discussion Forum

neil29 · 27th May 2008, 3:41 pm

Hi all. could someone let me know the voltage these units that ive removed from some C5s C7s actually work at. as i did not think to check before dismantling the machines..cheers neil.

HamishBoxer · 27th May 2008, 4:24 pm

12 volts as far as i know

neil29 · 3rd Jun 2008, 2:30 pm

Thanks. thats what i thought. only when connected to a tv set i cant seem to get it tuned in properly,also there is quite a loud buzz. does anyone have any ideas..cheers neil.

Steve_P · 3rd Jun 2008, 3:32 pm

What model did it come out of?

Anyway, get a variable power supply and ramp it up slowly. That way you'll find a voltage it works at.

Anyway, tune the TV to the unit on Black Level and Silence. Then put the video in but again ramp it up slowly. That way you'll find it's best level. It might not be terminated of course. 75 Ohms at a guess.

Are you sure it's a UK standard modulator.

Cheers,

Steve P.

neil29 · 3rd Jun 2008, 4:15 pm

Steve. the modulators came out of some sony C5s,C7s.so they should be ok?. and when there is no video input (at black level) its fine but when switched on the picture is overbright with that loud buzz.

..cheers neil.

Steve_P · 3rd Jun 2008, 4:17 pm

At a guess, not terminated. 75 Ohm resistor across the I/P should do.

Cheers,

Steve P.

neil29 · 3rd Jun 2008, 4:21 pm

Ok steve ill try that. thanks neil.

27th May 2008, 3:41 pm	#1
neil29 Heptode Join Date: Dec 2004 Location: Newport, Gwent, UK. Posts: 962	sony betamax modulator. Hi all. could someone let me know the voltage these units that ive removed from some C5s C7s actually work at. as i did not think to check before dismantling the machines..cheers neil.

27th May 2008, 4:24 pm	#2
HamishBoxer Dekatron Join Date: Aug 2007 Location: W.Butterwick, near Doncaster UK. Posts: 8,932	Re: sony betamax modulator. 12 volts as far as i know

3rd Jun 2008, 2:30 pm	#3
neil29 Heptode Join Date: Dec 2004 Location: Newport, Gwent, UK. Posts: 962	Re: sony betamax modulator. Thanks. thats what i thought. only when connected to a tv set i cant seem to get it tuned in properly,also there is quite a loud buzz. does anyone have any ideas..cheers neil.

3rd Jun 2008, 3:32 pm	#4
Steve_P Dekatron Join Date: Sep 2003 Location: Bolton, Greater Manchester, UK. Posts: 6,644	Re: sony betamax modulator. What model did it come out of? Anyway, get a variable power supply and ramp it up slowly. That way you'll find a voltage it works at. Anyway, tune the TV to the unit on Black Level and Silence. Then put the video in but again ramp it up slowly. That way you'll find it's best level. It might not be terminated of course. 75 Ohms at a guess. Are you sure it's a UK standard modulator. Cheers, Steve P. __________________ If we've always had it, why is the Car Boot open? You're not sneaking another Old TV in are you...?

3rd Jun 2008, 4:15 pm	#5
neil29 Heptode Join Date: Dec 2004 Location: Newport, Gwent, UK. Posts: 962	Re: sony betamax modulator. Steve. the modulators came out of some sony C5s,C7s.so they should be ok?. and when there is no video input (at black level) its fine but when switched on the picture is overbright with that loud buzz...cheers neil.

3rd Jun 2008, 4:17 pm	#6
Steve_P Dekatron Join Date: Sep 2003 Location: Bolton, Greater Manchester, UK. Posts: 6,644	Re: sony betamax modulator. At a guess, not terminated. 75 Ohm resistor across the I/P should do. Cheers, Steve P. __________________ If we've always had it, why is the Car Boot open? You're not sneaking another Old TV in are you...?

3rd Jun 2008, 4:21 pm	#7
neil29 Heptode Join Date: Dec 2004 Location: Newport, Gwent, UK. Posts: 962	Re: sony betamax modulator. Ok steve ill try that. thanks neil.