So close! Status & Rate indicator in one LED (Millennium 1)

[MrStab]

hi guys, i've started a new thread on this as my last one about weird Millennium Bypass issues went on a tangent into this topic.

basically i've built a Phase 45 for a friend and want to do what i can with minimal parts re. LEDs. mainly because i feel that having a lone LED that indicates both on/off status and rate will be a bit more sophisticated.

the story so far:
as most of my MOSFETs seem to be possessed, i've gone with an "old skool" Millennium 1 bypass circuit using a J201 which fulfils my needs nicely. no apparent seepage, thankfully. lol, "seepage". shame, as i've used M2 loads before. i think im just overlooking something dumb. but i digress.

here's my current setup:


(Thanks to RG for some suggestions, and also apologies for me probably not understanding them properly!)

when activated, the light stays on but brightness varies with intensity. when deactivated, the light properly flashes on and off. i could probably live with varying intensity when on, but i need it fully off when deactivated. suggestions?

i know this probably illustrates a poor understanding of how Mill-B. works, but attempts with anything other than the control line were unfruitful.

transistor-wise, all i have at my disposal at the moment are this lone 2n5088, a coupla 2n3904s, a bag of 2n5952s and some probably-defective BS170/2n7000s. any suggestions to keep it off when bypassed (and maybe make it flash "properly" instead of vary in intensity when activated?)

i'm not breadboarding this, but i do have a 100g reel of solder. well, i probably inhaled 90% of it earlier. i'm a n00b to experimenting with transistors but being a computer nerd, i'm already hooked by the possibilities.

cheers in advance!

[LaceSensor]

Save yourself the headache and buy a £3 3pdt switch?

[MrStab]

a 3PDT is probably a more straightforward solution which i might resort to in the end, but  i already have a DPDT and it would mean i can get round to putting it in an enclosure and posting it out sooner (i've already delayed it). it's a not wanting to keep my friend waiting and being ridiculously broke kinda deal. lol

besides, making things needlessly complicated is fun! er...
i probably imagined this in some less-than-ideal state of mind, but i'm sure i did read something where it was said that one of the reasons for still using the Millennium in the age of 3PDT abundance was for more niche applications anyway. at least that's what i'm telling myself. if no fix in a coupla days, i'll go the easy route.

even if i score those extra poles, the idea behind a transistor is to avoid loading down the LFO so i'd still try to use one with a 3PDT. hopefully it would work differently from trying to switch the power lines either to the MB or LED off the MB with a tranny, which somehow didn't work at all.

[Mark Hammer]

I combined status and rate into one LED for an EA tremolo by using a 3pdt tl switch in additional current limiting resistance to the led in bypass mode.  So, it always shows rate, just more dimly in bypass.

[MrStab]

i made the EA Trem with a regular rate indicator a few months back, i loved that thing! until it stopped working for absolutely no reason

so there's no real point to using a transistor? i thought otherwise because of reports of an LED "weakening" the EA Tremolo, actually (although it was fine for me).

guess it's more or less confirmed as do-able with a 3PDT then, if it's pretty much the same thing going on. cheers Mark. i'll give it till early Thursday morning when i order more parts. just in a devil's advocate kinda way, im still gonna ponder and inquire as to whether this is doable with the Millennium system(s), if only for curiosity's sake but maybe with added benefit for larger-scale builders or retrofitting or whatever. or other impatient, cheapskate a-holes such as myself.

i wonder why the NPN didn't work when i hooked it up before/after the LED anode itself. that was weird to my limited understanding. maybe something to do with the 2n5088's specs? can't remember if i tried anything else in there, but i'm lacking in any confirmed-working non-NPN's at the moment. i have no idea where they all go.

[slacker]

I would try using just the millennium bypass but instead of connecting the bottom of the LED to ground connect it to the output of your LFO.

[MrStab]

i totally misunderstood your post, Mark - my bad. i think i get you now lol.

mechanical switching seems so much more handy because you actually have a straightforward "alternative" path as opposed to nothing when off (with one part). it's just easier to cram more into my build budget when i choose a bunch of DPDTs.

Ian: yknow man... i just realised: that's how i had it set up at the very start, but then i had all those problems with my Millennium 2 but originally i thought it was how i had that wired and changed a load of stuff. now i have a working MB again, i should try that! damnit im trying it in 10 minutes! thanks lol

in so far as making mine flash bright-off-bright-off instead of bright-dim-bright when it's activated, all i can think of is using diodes or something to "gate" the signal as it were - to let power get through only when there's a pulse.

[Mark Hammer]

i totally misunderstood your post, Mark - my bad. i think i get you now lol.

mechanical switching seems so much more handy because you actually have a straightforward "alternative" path as opposed to nothing when off (with one part). it's just easier to cram more into my build budget when i choose a bunch of DPDTs.

No harm done.  If one is "committed by purchase" (   ) to use of DPDTs, then one alternative to consider is buffered bypass, where only the output needs to be switched, leaving a second set of contacts available to do whatever would normally be done by a 3rd set of contacts in a 3PDT.

My comment was for those who were thinking of status and rate indication, but simply wanted a cleaner interface and fewer holes in the chassis.  Another route to pursue is to use a tri-color (RGB) LED, and simply select which colour you want to show modulation rate.  So, perhaps blue for "effect on" and red for bypass.  Note that it would still be possible to provide for different brightnesses in effect and bypass mode by using different current limiting resistors for each colour.

[merlinb]

This is so easy it's painful- why's everyone running for the 3PDTs already?  

It is just possible that your LFO won't have enough guts to drive the LED directly, but will need a buffer (an emitter follower will do), but this shouldn't be necessary if you keep the LED current low.

[MrStab]

Mark: hmm...  despite haven pretty much started FX making by true bypassing a CryBaby, i'm not too opposed to giving away stuff with a perma-buffered output as i can't predict what other peoples' setups will be whereas i know where i, personally can get away with it. this build isn't for a gigging musician so i doubt they'd be anal about that. i'm just starting to wonder if it would be overkill to build whole buffers though, when the Phase 45 is by default 1-pot anyway, and maybe i could just put a rate and a status indicator on either side of where i would ordinarily put a row of 3 pots. but there's no fun in that lol. i'll consider this for future builds, maybe with a switch for more "nice appeal". gonna keep trying the suggested methods, though - keep blowing LED's by being careless

Merlin: so LFO into buffer into V+ on Millennium? i'll need to pick this up tomorrow and steal LEDs from a past project for now but i'll give it a go. currently using a white one so probably not so current-friendly.

cheers guys

[merlinb]

Merlin: so LFO into buffer into V+ on Millennium?

LFO into the base of a transistor, collector to 9V, emitter to V+ of Millennium bypass.

currently using a white one so probably not so current-friendly.

White LEDs are usually the efficient variety, so they actually need less current to be bright than, say, a cheap red LED. I usually find 1-2mA to be plenty bright enough, so I doubt you'd need the transistor. Easy enough to find out, though.

[MrStab]

works! NPN switching the power line to Millennium with LFO signal.

so i'd had it set up like this without the 2n5088 (current too weak i guess), i'd later had it with the 5088 but on the control line, and a few variations in-between, but my mind totally skirted around that particular setup. thanks Merlin! and everyone else!

i had to switch to a blue LED for now (i'm seriously sick of them thanks to my   own overuse, i've banned myself from buying more lol). i think there's a 1K resistor hooked up to it, which usually leaves it a lot brighter than it is now, but i only need to make it a wee bit brighter. i've just noticed it kinda starts to increase in brightness towards the end of the pulse, which gives it a more organic sort of vibe.

[MrStab]

prolly off-topic, but following a series of disasters including a necessary JFET change in the Phase 45 itself (it's been a bad week), why might connecting anything to the LFO now just stop the phasing and put out a fixed voltage until disconnected? this whole endeavour has somehow become more trouble than it needs be, but that's how i roll. ahem.

[armdnrdy]

Provide a drawing of what you have connected to where and I'm sure we'll figure it out.

[12Bass]

On my A/DA flanger clone, I used a bi-color LED.  Blue is driven by the LFO and indicates the rate, even in bypass.  Red indicates the pedal is active.  The pulsing of the blue LED combined with the red creates an interesting color mixing effect.

[MrStab]

as far as i can tell, Larry, absolutely nothing has changed except the new JFETs reading a little lower (1.62 as opposed to the previous 1.9). i've disconnected the whole Millenium thing for now. it's just the raw Phase 45 schematic only phasing stops when LFO is connected to anything else. doesn't really seem like a current draw issue as it's so abrupt and happens even with no LED at all.

IC voltages seem consistent, (tried replacing both ICs anyway), basic setup with ground from board going to each jack and battery in series, no apparent shorts. using adaptor so solid 9.33V without load. when i get home later i'll check for any other voltage differences between both states, besides the LFO voltage suddenly slamming on the brakes when hooked up.

unfortunately my parts supplier doesn't sell multi-coloured LEDs, but i did have a wee look because it does sound pretty cool.

[MrStab]

Edit: turns out it was current-related. seemed i needed just a bit more resistance for even the NPN to work.

hooking up the NPN actually seems to compromise the shape of the sweep, or at least notably slows down the effect. screw it, i've delayed it too much that i might just go with a basic on/off for now.