DIY AIR BRAKE WITHOUT THE RHEOSTAT?

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67plexi
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air brake

Post by 67plexi »

Im building a air brake I was shocked a plastic 2 ploe 6 posistion switch
I don't wan't to try it with the heat produced so I ordered a electro switch
# C4D0212N-A. What did ken use ??? fot a rotary switch.

Best regards, Steve.
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mhuss
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Re: DIY AIR BRAKE WITHOUT THE RHEOSTAT?

Post by mhuss »

I haven't had a "real/original' one here to compare, but I like mine a lot, it doesn't do too much to the tone, and the price is right. :)

--mark
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Ron Worley
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Re: DIY AIR BRAKE WITHOUT THE RHEOSTAT?

Post by Ron Worley »

Here's alternative Ceramic switch that I have added to the BOMs that I will post soon-

CK1455 Mouser PN I think.....

Ron
dehughes
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Re: DIY AIR BRAKE WITHOUT THE RHEOSTAT?

Post by dehughes »

Mouser part # CK1455 is the same one as on past BOM's for the Airbrake.

C4D0212N-A is different...much more expensive, but might be worth it.

Can anyone speak to which is preferable? Is a ceramic one necessary, or just "overbuilding" for the sake of overbuilding? I like overbuilding, but....
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Re: DIY AIR BRAKE WITHOUT THE RHEOSTAT?

Post by dehughes »

Bump for info regarding the two potential rotary switches...is the spendy one worth it, or should I just go with the regular Lorlin one? I'm curious being as I don't know if the Airbrake really will put too much stress in terms of current and/or heat on that Lorlin switch...

Thanks.
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mhuss
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Re: DIY AIR BRAKE WITHOUT THE RHEOSTAT?

Post by mhuss »

I've had no problems with the Lorin switch, but I've never used on an amp of more than 50 watts.

--mark
dehughes
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Re: DIY AIR BRAKE WITHOUT THE RHEOSTAT?

Post by dehughes »

mhuss wrote:I've had no problems with the Lorin switch, but I've never used on an amp of more than 50 watts.

--mark
Thanks Mark. Much appreciated. The amp I'd be using it with would be in the 20-25w range, so I'm pretty sure I'm safe.

Again, thanks for all your help...the schematic, etc... I couldn't do all this without the help of people on this board.
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rosspix
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Re: DIY AIR BRAKE WITHOUT THE RHEOSTAT?

Post by rosspix »

Hi all - newbie here.

I'm looking to build an Airbrake but with a couple of added features. To whit, a couple of questions if I may:

1. Could a fan run off the o/p voltage (as in the THD Hotplate)? Using Ted Weber's l-pad calculator, I reckon on there being ~17V across R1 at -16dB.

2. Are bright/deep switches a good idea? I'm guessing that, for the sake of a couple of DPDT toggles and suitable caps, it could be worth doing...

3. I'm a sucker for lights and all things shiny... If I was to stick a bulb into the circuit (maybe across the fan/R1), would it have any adverse effect on the tone, since I've read that a bulb may also be used to attenuate the signal?

Of course, this could all well be moot - Ken didn't see fit to put the features on the original AB, and if it ain't broke...

TIA for your help and advice - this forum has become regular reading for me!

Cheers,


Ross
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fishy
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Re: DIY AIR BRAKE WITHOUT THE RHEOSTAT?

Post by fishy »

rosspix wrote: Are bright/deep switches a good idea? I'm guessing that, for the sake of a couple of DPDT toggles and suitable caps, it could be worth doing...
I believe some people prefer the cap and some do not so I don't see why you could not have it switchable.
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Re: DIY AIR BRAKE WITHOUT THE RHEOSTAT?

Post by dehughes »

Cool...I like switches and knobs...especially if they make things sound "better".
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markr14850
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switches

Post by markr14850 »

A while back, I wanted a bit more flexibility in the sound of the airbrake I'd built, so I added two switches.

The first was bright/normal/hi-cut. This worked on the existing cap on the rheostat which acts like an amp volume control bright cap. In bright mode, it's as normally wired. In normal mode, it is disengaged. In hi-cut mode, it goes to ground.

The second switch is normal/bass-boost/extra-bass-boost. It works by switching in a couple of fairly large film caps to bypass the attenuator. At the moment, I don't remember what values I ended up with for these (probably between 1-10uf), or which (if any) tap on the fixed resistor I fed them from. But just play with it, you'll find something that suits you.

I have no idea what these changes do to the load that the OT sees. I have to believe that the bass mod makes the OT see more of the speaker, and that should be good. But caveat emptor.
rosspix
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Re: DIY AIR BRAKE WITHOUT THE RHEOSTAT?

Post by rosspix »

Thanks, mark - the bright/normal/hi-cut should give me everything I need.

Now to order the parts and play!
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dehughes
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Re: DIY AIR BRAKE WITHOUT THE RHEOSTAT?

Post by dehughes »

Ordered A BUNCH of parts from Mouser yesterday...fingers crossed...
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Noel Grassy
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Re: DIY AIR BRAKE WITHOUT THE RHEOSTAT?

Post by Noel Grassy »

Ross,
If you get that fan working let us know. I've got my fan mounted on the opposite long end from the input jack. But I have not drilled a hole for the DC inlet yet and I'd like to use some of the stray juice from within. :wink:

Thanks for the idea.
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rosspix
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Re: DIY AIR BRAKE WITHOUT THE RHEOSTAT?

Post by rosspix »

It might be a while - the ordering of parts will have to wait until after the holidays, I fear...

...such are the perils of parenthood ;-)

But yes, of course - I'll report back if I manage to get things up 'n' running effectively.
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