E-Waste

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C Moore
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E-Waste

Post by C Moore »

I was "gifted" a JBL Bass-20. Both speakers are blown bad. Even if new, I have no use foe anything like this. I measured the PT secondary, but I cannot remember what it was.....18 VAC, or something like that.?
Is there any use for this.? Even to strip something off of it, and use as a piece of test equipment.....or should I just e-waste the whole "kit and kaboodle".?
Thanks
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Stevem
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Re: E-Waste

Post by Stevem »

You could use its power supply as the bias supply for tube amp development rig, thats about all I could think of!
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sluckey
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Re: E-Waste

Post by sluckey »

That heatsink may be useful for building a bench dummy load?
C Moore
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Re: E-Waste

Post by C Moore »

Those are some good ideas.
Regards the dummy load.....I guess look up the power-out spec of the amp, or the power transistors to get an idea of how much heat it can dissipate.?
Thanks
sluckey
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Re: E-Waste

Post by sluckey »

That's way too technical. Just open it up and see if there is enough flat surface area to mount some power resistors on it. Kinda like this...
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C Moore
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Re: E-Waste

Post by C Moore »

It is NOT too technical.....it IS too stupid. :)
You said "dummy load" and I got tunnel vision...thinking we were talking about resistance. I forgot we were just talking about a bare Heat Sink....... :oops:
eniam rognab
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Re: E-Waste

Post by eniam rognab »

that PT probably can put out some serious current, you 'could' build a cool SS amp with it (run and hide emoticon) CT? if so you can generate a +/- supply with a bridge rectifier... just a thought

or build a benchtop variable voltage regulated DC supply with like a LM317, or build a sweet pedal board power supply, you could run a crazy rig off of that, like the Edge's pedal board

i dunno, just throwing idears out there, lemme know if you like anything, i could point you in some direction hopefully

kindly,
neal
C Moore
Posts: 1266
Joined: Mon Oct 22, 2007 9:28 am
Location: USA, California, 94585

Re: E-Waste

Post by C Moore »

eniam rognab wrote:that PT probably can put out some serious current, you 'could' build a cool SS amp with it (run and hide emoticon) CT? if so you can generate a +/- supply with a bridge rectifier... just a thought

or build a benchtop variable voltage regulated DC supply with like a LM317, or build a sweet pedal board power supply, you could run a crazy rig off of that, like the Edge's pedal board

i dunno, just throwing idears out there, lemme know if you like anything, i could point you in some direction hopefully

kindly,
neal
OK....."or build a bench-top variable voltage regulated DC supply with like a LM317"
THAT sounds like it could be a handy "thing" to have around. :)
eniam rognab
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Re: E-Waste

Post by eniam rognab »

cool! glad i could provide some help! definitely a handy item to have on hand :lol:

not all LM317 are created equal, and maybe you will have too high of an input voltage...

check out a TL783C from Texas Instruments. look at the datasheet for a sample schematic, these can handle way more volts than a 317.

also, notice in the datasheet at the top highlighted "samples" i got three for free! they want to put these in the hands of designers so bigger orders will be placed. all you need is a business license or a school email. plus they are very cheap anyway, i would go for the TL783C if i was you, i made one with GREAT results!! ive got a +35v to 1.25v regulated supply, very handy

have fun!
neal

edit: don't ewaste!! at least until you pull all the useful stuff out first :D
Last edited by eniam rognab on Tue Aug 12, 2014 1:46 am, edited 1 time in total.
eniam rognab
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Re: E-Waste

Post by eniam rognab »

aww nuts, no 'samples' on the datasheet :oops: .... didnt mean to get your hopes up... still, they are probably like $2 or something probably less

datasheet page 9 for schematic, one of the simplest builds you will ever build probably! :lol: :lol:
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