I have a Panasonic SB-WA930 subwoofer, and want to power it up....Have schematics and pcb layouts, and the pinout for the 25-pin cable to it from the DVD player. Will not power up without DVD player plugged in...There must be some "permissives" that I can bypass/ground/fool to get it to work w/o the DVD unit, but don't know enough to figure it out. Any ideas/experience with this type of thing? All docs are in service manual (PANASONIC SB-WA930EE Service Manual free download, schematics, eeprom, repair info for electronics , click on "Get Manual", so-so pages attached). Thanks!
Home theatre amp update!
Have confirmed all six amps work (stereo front & rear, center & sub), and get "rated" power from each. For ex: center chl puts out 95Vp-p and 4.0A, before clipping. Allowing for scope probe impedance error and DMM reading a 1KHz signal, E x I x 0.707 = 270W (matches factory manual). For whatever that's worth....
Of course, each amp needs a preamp, and I will be putting everything from a guitar to a keyboard to a mixing board into these amps. The preamp I'm testing is from an old set of PC speakers (are you getting the idea this is low budget....?), which boosts a guitar sufficiently, as well as an MP3 player (when it's gain is lowered considerably - yes, two very different inputs!). I NEED to keep the preamp from clipping, and teenagers will be operating this.....
So I thought about an LED clip indicator - like a fuzz box I built once.... when the LED clips it lights up! Determine the proper series resistor to not let it clip until just before the preamp does, and voila??? Anyone done anything like this?
I need ingenuity/simplicity, not "just buy a stereo compressor-limiter...." Thanks!
Have confirmed all six amps work (stereo front & rear, center & sub), and get "rated" power from each. For ex: center chl puts out 95Vp-p and 4.0A, before clipping. Allowing for scope probe impedance error and DMM reading a 1KHz signal, E x I x 0.707 = 270W (matches factory manual). For whatever that's worth....
Of course, each amp needs a preamp, and I will be putting everything from a guitar to a keyboard to a mixing board into these amps. The preamp I'm testing is from an old set of PC speakers (are you getting the idea this is low budget....?), which boosts a guitar sufficiently, as well as an MP3 player (when it's gain is lowered considerably - yes, two very different inputs!). I NEED to keep the preamp from clipping, and teenagers will be operating this.....
So I thought about an LED clip indicator - like a fuzz box I built once.... when the LED clips it lights up! Determine the proper series resistor to not let it clip until just before the preamp does, and voila??? Anyone done anything like this?
I need ingenuity/simplicity, not "just buy a stereo compressor-limiter...." Thanks!
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