[blipblop]

Once again, I'm sure I'm merely illustrating my ignorance, but...

So far, the various incarnations of the PPA I've seen around these boards all make use of a regular switch - a conventional toggle, pushbutton, or even a momentary switch (with added circuitry) - to power on the PPA.

Has anyone used one of those devices that combine volume control and power-on in one mechanism? I don't know the name of it, but its quite popular on car radios, where the radio is turned on by turning the volume knob, where physical resistance is felt as the radio is turned on, and then the knob is freed to turn for volume control.

I thought this would be a great idea since (1) it would eliminate the need for two seperate parts, and (2) would eliminate the risk of turning on the Amp with the volume cranked up, and blowing out one's ears (i've done this before and it hurts!).

Perhaps its already been discussed here, but I haven't seen it or don't recognize the proper name for it, if infact, it has been discussed.

 

[Nisbeth]

The component used is a pot with a built in switch. The idea sounds OK to me, but you'll be hard pressed to find a pot in (anything like) the same quality as an Alps blue.


/U.


EDIT: I've seen an Alps RK09 with built in switch. Maybe something for a Mint or a pocket CMoy?

 

[guzzler]

with a little ingenuity you could rig up a switch on the inside of the knob that connects when turned past a certain point, probably be easiest as a variation of the momentary switch so using a low contact pressure switch drilled through the panel behind the knob with some sort of snib on the underside of the knob. You probably wouldn't feel any physical resistance but it would perform the same

g

 

[stereth]

Yeah, that wouldn't be too hard to make. You need some kind of a cam on the pot shaft, and you can use a spring-loaded lever switch for power. Make sure the end of the cam is what holds the switch down, else it will try to rotate the pot.

 

[blipblop]

Seeing as your recommendations both refer to some variation of a jerry-rigging of a POT, am i correct to think that this part is hard to find?

 

[Nisbeth]

...In a decent quality, yes! If quality is secondary, your local electronics store (Radio Shack?) will probabaly have one

/U.

 

[stereth]

Pot = potientiometer. The volume control. You can extend the shaft and add a switch onto that.

I made a guitar amp in a mint tin with a power switch like that. Of course, the amp was mono, so it was a single pot...much easier to find with a switch.