Switching Circuits through Relays

[hardcore misery]

I don't have a complete circuit yet, pero I have the concepts, magpapatulong sana ako sa design nito.

Bistable Flip-flop/Multivibrator will be triggered by a switch (latching circuit kasi tong flip-flops diba?) then young output nung flip=flop will trigger the Relays, supposed to be, tatlong relays ang naisip kong gamitin.1st relay serves for latching the transistor(yung trigger na makakapag pa-ON ng relays, di ko nga alam kung yung transistor sa flip-flop or, the transistor driven by the flip-flop) yung 2nd relay naman, ay yung switch for two devices, the 3rd relay will be for the LED indicators.

**optional yung 3rd relay.

eto kasi yung project ko(for hobby lang and educational purposes na rin) the circuit will serve as a truebypass looper for guitar pedals, this will be a substitute for 3pdt footswitches used on loopers. although mas complex/bulky tong naisip kong project

Follow-up ko na lang yung block diagram. Magpapatulong sana ako sa design ng flip-flops eh TIA.

[alyas]

Suggestion ko lang para mas maganda at clickless (walang popping sound) yung switching of inputs/outputs instead of relays, use semiconductor analog switches.  Meron niyan sa Alexan.  You can use d-flip flops for the input trigger para press on press off yung switching.

[hardcore misery]

Suggestion ko lang para mas maganda at clickless (walang popping sound) yung switching of inputs/outputs instead of relays, use semiconductor analog switches.  Meron niyan sa Alexan.  You can use d-flip flops for the input trigger para press on press off yung switching.

Mechanical switching pa rin ba sir yung magagawa niya? hindi na siya true bypassed looper.. pero I might consider pa rin yan, para dun sa ibang pedals na may switching gap sa pag engage/disengage nila.

[Woots29]

ah cmos 405n will do or 4066

[hardcore misery]

I've come across sa site na to:

http://www.members.shaw.ca/roma/switching-2.html

kung lalagayan ng capacitors sa input, may tone suck na, kung di naman lalagyan, possible daw na may noise...

[Woots29]

ok lang may cap bro. basta mataas, at nakaseries sa input. kung shunted, un masama

[hardcore misery]

ok lang may cap bro. basta mataas, at nakaseries sa input. kung shunted, un masama

tama, hehe, nalimutan ko, pag shunted pala ang caps, may tonesuck na..

di ko pa masyadong magets yung circuit sa site..yung mga 10k resistors na nakaseries sa output ng effects, edi may signal loss pa din?

[Woots29]

wel that 10k resistors doesnt give a big signal loss. since effects processors are high impedance (acording sa mga nabuksan ko at circuits in the web na rin) hindi ito makakapekto sa signal. parang mixing na rin ang gamit nyan. so its ok na yan ang value 

[hardcore misery]

sige standby muna, hindi ko masyadong gets yung circuit sa taas eh. hehehe

[alyas]

I dont get the effects circuit above??  Usually effects processors are cascaded or series.  Anong kalseng effect ba ang loopers??  Pasensiya na at frustrated guitarist kasi ako eh.

With the circuit above, the 10k resistors are negligible as the effects would already have boosted the circuit a a certain degree.  The main purpose is to mix the signals to a single output without loading the output stage of the other input effects.

[Woots29]

oo nga no, cascaded namn ang mga effects procs, hmm nga pala sir hardcore, anu ba balak u jan?

[hardcore misery]

truebypass looper kasi yung gusto kong mangyari diyan.

truebypass = sa isang wire lang dadaaan yung signal, di tulad sa mga buffered effects na, colored na yung tone or bawas na yung tone, although, ok din yung buffered tone, pero ayun nga, gusto ko na truebypassed yung effects na gagamitin ko...

3pdt footswitches ang karaniwang gamit for TB loopers, mechanical switch lang kaso mahal, di ko pa alam kugn anong cost nitong semicon anlog switches circuit na to, kung mas mahal siya sa 3pdt, then i'll go for 3pdts na.  pero etong circuit, may application parin dun sa mga effects na may switching gap problem... kaya may katuturan pa rin to. hahahaha.

[Woots29]

actualy mas mura yang ic na 4066 or equivalent

hmm talagang concern ka sa tone ha, cge simulate ko ito tignan ko kung may discoloration nga ngyayari. balitaan kita.

[hardcore misery]

hehehe. iba talaga ang tunog nung clean tone na dumaan sa flip-flops kesa sa clean tone na dumaan lang sa isang wire. pwedeng mas bright yung tone na hindi truebypassed, or pwede ding bawas na yung high frequencies niya.

[Woots29]

wel hindi ko pa nasimulate

pero sa tingin ko walang malaking pagbabago sa sound kapag dumaan jan

[hardcore misery]

wel hindi ko pa nasimulate

pero sa tingin ko walang malaking pagbabago sa sound kapag dumaan jan

were you refering dun sa circuit sa taas? yung mga capacitors in series input at amp (0.1uF at 2uF) diba may minimal reactance parin yun? AC signal yung signal ng gitara, then Xc = 1 / (2pifC) educate me! hahaha

[Woots29]

formulas are good,. pero may mga rason bakit ganyan nilagay.

im desgning preamplifers and usually im using 0.1uf at inputs without degrading sound quality.
im not engineer, pero i understand the circuit 

see this circuit

http://www.rane.com/pdf/old/ac22b2sch.pdf

see c203 c204 c205

[rdpzycho]

were you refering dun sa circuit sa taas? yung mga capacitors in series input at amp (0.1uF at 2uF) diba may minimal reactance parin yun? AC signal yung signal ng gitara, then Xc = 1 / (2pifC) educate me! hahaha

mag-act kasi 'yan as high pass filter in combination sa input impedance nung effects such that fc = 1 / (2piRC). protection na rin 'yung capacitor pero kung concerned ka sa coloration nung capacitor, meron din 'tong THD+N graph (search for Maxim's app note). kung gusto na sobrang linis pero with protection sa DC, high order DC servo ang kailangan na ang cutoff nasa 0.1Hz, 'yun lang pag mali ang design, mag-oscillate.

hindi ako sure kung para saan 'tong box pero mas maganda siguro kung multiplexer 'yung switch especially kung may noise output 'yung effect circuit kapag walang input. sa diagram kasi naka-mix na siya kaagad kahit walang input 'yung effect, pwede ka pa rin maka-pick up ng noise doon. igrou-ground lang naman or padadaanin 'yung output.

[hardcore misery]

formulas are good,. pero may mga rason bakit ganyan nilagay.

im desgning preamplifers and usually im using 0.1uf at inputs without degrading sound quality.
im not engineer, pero i understand the circuit 

see this circuit

http://www.rane.com/pdf/old/ac22b2sch.pdf

see c203 c204 c205

@woots
yeah bro, I know na knowledgeable ka dito, kaya nga masaya ako at may makakatulong sa akin, ako kahit engr. na, di ganun kalawak ang experience ko sa technical (di talaga masyadong naituro sa amin during school days) then ikaw, technician ka, so talagang marami kang alam sa actual design or anything...

about preamps, papaturo ako sainyo sa design ha, di pa ako nakakapagreview ng basic opamp theories should I make a separate thread? or dito nalang? hehehe... tulungan niyo ako ha!

@rdzypho

talagang technikalan ang reply mo sir, di ko masyadong ma digest, pero I'm willing to learn!!!

high pass filter nga ano, low pass kung shunted ang capacitor, pero may coloration bang nagagawa yung dalawang capacitors na yun?

[rdpzycho]

hindi ko makita 'yung links, merong coloration 'yan dependent sa gagamitin mong capacitor. pakinggang mo na lang din kung ok na sayo. kung ceramics gagamitin mo, NPO dapat para mas stable ang capacitance, kapag 'di kasi stable mas mapapansin 'yung coloration.

eto nakita ko na ulit:

http://www.maxim-ic.com/appnotes.cfm/an_pk/3171
http://www.maxim-ic.com/appnotes.cfm/an_pk/4333

pero 'di naman siguro gaanong pansin 'yung ibang distortion.