Electronics Wiring up a remote control & controlling it by PC replay board

Ok, it doesnt seem like the 220 ohm resister is not working for my controller. I hooked it up to a volt meter and its pushing ~5.12 with the resister on it!

Any more ideas?

*UPDATE*
I also used a 220k ohm resister. When i used one it dropped the volts to ~4.4 volts. Then using 2 it drops to around ~3.5 volts. Using 3 drops it way beyound what i need. So i deside to hook it up using 2 resisters and it doesnt work.....

David

 

440k ohms is way too much... the board could only get a few uA's

use 3 diodes instead

 

Radioshack only carrys the 1-Watt Zener Diode (12.0v) & 1W Zener Diode (5.1v). Which one do i need? Also, they carry other diodes, check out http://www.radioshack.com/search.asp?find=diode&site=search&SRC=1 and tell me which one i need.

Thanks,
David

 

Try here:
http://www.goldmine-elec-products.com/prodinfo.asp?number=G13476A&variation=&aitem=4&mitem=12

I think they have a minimum order, but you can find quite a bit of other stuff you may need as well.

Another good place to check is http://www.allelectronics.com

 

no -- regualr silicon diodes, not zeners. you connect them the right way in series with the power supply, due to their foward voltage each one drops .7v; that is what i was trying to explain before :

these will do:
http://www.radioshack.com/product.a...name=CTLG_011_002_006_000&product_id=276-1620

 

Sorry, thought he was referring to this...

 

yeah except i didnt know you were workin outta the shack, i.e. shitty selection

 

Agreed
Shack good for only "absolute last resort" and you have money to waste...

 

QFT... i walk in there for like a transistor and the guy is like "thattle be thrity four ninty nine"... soooo expensive 1 LED is like a buck. but i set up a UPS busnass account to my house and i dropship stuff overnight from digikey, and that is cheaper then radshack... sais alot

 

I don't want to end up hijacking the thread with this, but you ever try even asking them for a transistor? They look at you like you're from another planet. I was in dire need of some snappable pin headers one time, and went in to the shack to see if they had any (this was sometime in December) and the salesperson looked at me when I asked for them and said, "Oh, we must be out, we sell a lot of those this time of year )....yeah, o.k.

 

hey i just wanted to double check before you fried something by listing to me....

first, the diode array. they are all in series:


when i hooked this up to a DMM, it said 4.5V!!! but the voltage drop varies with current, as soon as i put an LED on the line, it droped to 2.4 volts (at the end). i had an extra diode solderd on so i could move the alligator clip back and forth to test diffrent voltages

i hooked up this small LCD clock, normaly run by a 3 volt LI batt


i at first hooked it up using 4 diodes. the screen was dim, and the speaker was muted. i moved the aligator clip down 1 dode. the DMM read 3.3, but the display lit up perfectly.




i was glad (but not suprised, lol) to see it working exactly as predicted.

note -- when the speaker played a little song, the voltage droped to 2.8V. so even if it is a little high with 3 diodes, id leave it, because once it starts transmitting, it may drop down a little.

 

OK, thanks for all the replys! I will go by Radioshack and get some and try them out tomorrow night.

By chance, can u give me a list of diodes that i would only need one of or maybe just 2 if i can find an electroinc shop around here with more of a selection?

Thanks again!

David

 

well, radio shack sells 50 of thos diodes for $2

most FV drops are about the same, except germanium which is .2v; the main diffrence is how the voltage drop relates to current draw. bigger diodes will take more current before they get the same drop. unless you can find the 3 volt zener you would need the same number

if you have a junk pile of old electronics you can salvage the diodes, but it is cheaper to buy them (even from ratshack)

 

Welp, it works!

Thanks again theshadow27 and others who have the greatest knowledge that I know of on th forum!

Thanks again,
David

 

Ok I’ve been thinking. It works when I hook it up to the relay but it seems that when I move the inferred LED out of the line of site then back it turns on (or off) again (even if I turned it off before moving the LED.)

Now I’m thinking that I could bypass the relays all together and just use the 8 outputs off the port on the board. Although I am unable to make it work by hooking them up since it doesn’t seem to power them. I tested it with a LED and it lights up on/off. When I put both wires to one of the 8 ports, it doesn’t turn on/off the receiver.

Any ideas on how I can do this?

David

 

it sounds like your program isn’t shutting off the relays properly. do you hear both clicks: one when you switch it on, and a second when you switch it off? if you are writing your own code, i would suggest only pressing the button for a short period of time, with only one button pressed at any given time.

do not connect the parallel port outputs directly to the remote, that is the easiest way to fry it. it does not have separate MCU inputs for each key; they are in an active scanning matrix: it applies voltage to the rows sequentially, and then checks the columns for voltage. applying voltage that doesn’t come from the scanning chip will cause damage, whether you see it or not, because it runs something like .5v normally.

if the relays don’t work, nothing will - relays are the best form of isolation available. my suggestion is to get it working with the relay before you try anything else to get rid of the click. the next best option is an optoisolator, but because of the transistor in it, you will need a certain voltage before it will conduct. if opto's FV is too high, you’ll have to get an analogue switch of some sort - probably 2 FETs back to back.

 

Ok, I have another problem that popped up its little head.

I bought a 13.5/30v AC to DC converter for use on my 600 watt amp. Of course running 13.5 isn’t enough to drive 2 12" woofers so I use the 30v. The 30v works fine although I am concerned about blowing something up (I think the amps input is only rated at max 20v. Also I am having trouble turning on/off the amp via the remote wire. It doesn’t seem to want to turn off when I disconnect 12v to the remote (it should turn off when no 12v is found on the remote wire).

So is there any way I can use those diodes so that i can crank down the 30v (which is registering about ~25v when the amp is on without subs bumping) down to about 18v?

I don’t even know that turning down the volts will have any impact on the amp turning on/off by the remote wire but will see.

David