hi & need help

[KMoffett]

eric,

I think it would be better to put multiple C3s and R1s all on the input of the analog switch with P1s and the sensors. Otherwise C3/R1 have to equilibrate with each new selection. Not having built this, I don't know if the time would or would not be significant.

Ken

 

[ericgibbs]

eric,

I think it would be better to put multiple C3s and R1s all on the input of the analog switch with P1s and the sensors. Otherwise C3/R1 have to equilibrate with each new selection. Not having built this, I don't know if the time would or would not be significant.

Ken

hi Ken,

I have tried looking up the word equilibrate, I cant find it.
**broken link removed**

Its a good descriptive word and I'll use it often.

You could be correct ref the C3, as we dont know the characteristics of the probes and soil.. I would try it without first, add if required.

hi Scott.
Do you need a circuit or can you go solo the rest of the way.?

BTW: Its an old English battle flag..

 

[KMoffett]

eric,

It has a nice feel rolling off the tongue.

e·quil·i·brate (-kwl-brt)
v. e·quil·i·brat·ed, e·quil·i·brat·ing, e·quil·i·brates
v.intr.
To be in or bring about equilibrium.
v.tr.
To maintain in or bring into equilibrium.
e·quili·bration n.
e·quili·bra·tory (-br-tôr, -tr) adj.

 

[haggis@home]

hi Eric

yes please if you could , i still have a long way to go . are you a electronic engineer if i may ask ? i was blown away with the talk you and the others were saying , i can only wish i will have such knowledge in a year or ten

i was planning on using stainless steel rods but i have seen people use double sided copper pcb board , what do you think would be best ? will the ac power affect the plants ?
and one last question . years ago i got a book for my birthday called getting started in electronics by Forrest m mims , is this book still recommended or available ?

again thanks to all who took the time to reply and big thanks to Eric

 

[Mike_2545]

I would keep copper away from plants. It is a nice herbicide.

 

[haggis@home]

thank you mike , looks like stainless is the way forward then

 

[ericgibbs]

hi Scott,
Look this over, lets know what you think.

Uses a HEF4066, HEF4017 and HEF4093 ic, plus the bits from the original dwg.

Its designed to step thru automatically or manual.

Its for 4, but can be extended to 8 with another HEF4066

 

[haggis@home]

smashing , thank you for your time and effort eric ...

quick question about the dwg , and please don't take offence . but it confuses me , i sort of see were the original circuit was/is but on the right towards the middle there are two (4093) were do they go in relation to the rest of the circuit ? ..

if i was to put your drawing in to a pcb program would it arrange the circuit for me ? and also would you have a component list for the new parts ? i feel bad asking you for more after you have done so much , but if you don't ask you don't get

 

[ericgibbs]

smashing , thank you for your time and effort eric ...

quick question about the dwg , and please don't take offence . but it confuses me , i sort of see were the original circuit was/is but on the right towards the middle there are two (4093) were do they go in relation to the rest of the circuit ? ..

if i was to put your drawing in to a pcb program would it arrange the circuit for me ? and also would you have a component list for the new parts ? i feel bad asking you for more after you have done so much , but if you don't ask you don't get

hi,
The 'spare gates' of the 4093 are not used, so their inputs are tied low.

I dont have a parts list, the part values are marked on the dwg.
The ic's HEF4066, HEF4017 and HEF4093.
[these are CMOS, so make sure they dont get damaged by static electricity when handling]
Note: the one 4093 has 4 gates inside, 2 used, 2 not.

I dont use an auto router for converting circuits to pcb layouts, so I can't be sure about autorouting, which pcb layout program do you have.?

Wire the rest of the LM3914 and psu, as per the original circuit.

Use twisted wires [pair] for connecting from the pcb to the sensor probes, minimise electrical noise.

 

[haggis@home]

hi eric .. i use express pcb , i am at the moment trying to draw all the circuit by hand on the pc .. its not easy and is very time consuming , but its helping me learn and that is the important bit

 

[ericgibbs]

hi eric .. i use express pcb , i am at the moment trying to draw all the circuit by hand on the pc .. its not easy and is very time consuming , but its helping me learn and that is the important bit

hi,
I use expresssch also, I'll post the original.

It will have a *.txt extension so that I can post it, you change it back to *.sch

its Plants2.sch

 

[haggis@home]

hi eric ..

i am so sorry to ask you this but i am having trouble joining the original circuit to your one , i know i would be taking the p1$$ asking you this but would you be able to join them together for me ?

i used the pcb program you use and its the first time i have used it , and i am a bit lost , if you cant i understand as you have done too much all ready .


lots of thanks


scott

 

[Roff]

Scott, you previously said you wanted 4 separate banks of LEDs. Have you dropped that requirement?

 

[haggis@home]

hi roff ..

it would have been nice but beggars can not be choosers , the circuit that Eric made switches between the four channels or i can cycle through them manually .

 

[Roff]

hi roff ..

it would have been nice but beggars can not be choosers , the circuit that Eric made switches between the four channels or i can cycle through them manually .

Perhaps Eric either misunderstood your wishes, or took off on a tangent that intrigued him.

 

[ericgibbs]

Perhaps Eric either misunderstood your wishes, or took off on a tangent that intrigued him.

hi Ron,
I can honestly say I have never 'tanned a gent' in my life...

Its just that my inbuilt reluctance to spend more money than necessary to do the same job, kicked it.

With the addition of another 4066 Scott can scan 8 plants.

There are ways he could have an automatic warning if the pots are drying out.


Scott:
I would recommend that you 'prove' that the probe and psu method work before doing a pcb layout.
Look at this image

Do a quick bench test of a probe/psu.. no need for the LM3914, just the 100K and 10uF load and measure the voltage across the 100K with a DVM.

 

[haggis@home]

hi Eric ..

no worries i will hopefully be ordering the parts tomorrow night (can you recommend a good online shop that's not to expensive in the uk ? ) . i have a dmm so will give you the readings asap

 

[ericgibbs]

hi Eric ..

no worries i will hopefully be ordering the parts tomorrow night (can you recommend a good online shop that's not to expensive in the uk ? ) . i have a dmm so will give you the readings asap

hi,
If your order is > £20 then from Farnell Leeds, you can order on line, with free P&P.

also RapidElectronics, Maplins.

BTW: you could use your spare PC psu as the supply for the project and a small low cost mains to 6V transformer to give the 'ac' for the probes.
Lets know how the tests go.

 

[haggis@home]

hi eric

would you look at this list at tell me if it looks ok for what i need ?

**broken link removed**[/IMG]

 

[ericgibbs]

hi Scott,
Which circuit are you going to build.????