Back to post # 9 except am using a short strip of cardboard 2 pinholes crosswise spaced .1" in center.
Tx tight fit to strip with a drop of quick setting epoxy on Tx, adjusted for maximum output, taped in place to cure. Rx for testing is TEMT1020, SMD, gull wing, but will switch to TEMT1000, inverted gull wing for easier mounting. I'll try to come up with a sketch soon. Had second covid shot today will see what tomorrow brings to this 94 year old.

 

Back to post # 9 except am using a short strip of cardboard 2 pinholes crosswise spaced .1" in center.
Tx tight fit to strip with a drop of quick setting epoxy on Tx, adjusted for maximum output, taped in place to cure. Rx for testing is TEMT1020, SMD, gull wing, but will switch to TEMT1000, inverted gull wing for easier mounting. I'll try to come up with a sketch soon. Had second covid shot today will see what tomorrow brings to this 94 year old.

Oh wow hold on tight there! And thanks for the answer

 

10- TEMT1000's on the way to AZ, USA. Right arm only slightly hurts with direct pressure.

 

Okay. Back here we have some new cases recorded from African covid. Apparently, this covid is immune to the vaccine that we currently use.

 

All Tx aimed & anchored.

 

Okay. Please show a picture of your construction if possible when you finished

 

TEMT1000's arrived this evening.
Do you have a deadline for the project?

 

No fixed deadline. Currently we use whatever sensors we had available which are:
https://www3.panasonic.biz/ac/ae/search_num/index.jsp?c=detail&part_no=CX-421

They work, but it is not convenient since they only operate in a very narrow beam and operators need to ensure that they put a hand exactly below the sensor to toggle it which is not efficient/convenient.

We also have some Emmiters :https://www.digikey.com/en/products/detail/everlight-electronics-co-ltd/IR333-A/2675571
And receivers : https://www.digikey.com/en/products/detail/osram-opto-semiconductors-inc/SFH-203-FA/607284

I have got them from the local shop just for testing, now just realised that receiver peak wavelength is 900nm while the emmiter is 940nm. I hope that I can get atleast some sort of results out of that

 

We have an IR curtain. 6 pairs, TX- VSLY5850, Rx- TEMT1000. A hand can move about any where within the 28 cm X 40 cm opening and receive one output-- but if only a finger is waved within the opening there can be multiple outputs. Most of this problem could be mitigated by adding a pulse stretcher or retrigerable monostable multivibrator. ( spell check doesn't like my spelling of these words ) maybe up to one or two seconds. I will be back late Monday

 

With just a short time available today, I lashed up a pulse stretcher with : 1N4148 diode, 1M pot, 10 uF cap., & CD74HC14 schmitt trigger. @ 100k, pulse delayed about 1 second allowing only a single pulse while waving a finger in opening but not allowing retrieval of 2 objects without detection.

 

With just a short time available today, I lashed up a pulse stretcher with : 1N4148 diode, 1M pot, 10 uF cap., & CD74HC14 schmitt trigger. @ 100k, pulse delayed about 1 second allowing only a single pulse while waving a finger in opening but not allowing retrieval of 2 objects without detection.

Thanks for the information you have shared. Can you clarify what do you mean by saying not allowing retrieval of 2 objects without detection?

 

Maybe the delay should be adjustable for the system shake down as too short a delay might allow
extraneous hits & too long of a delay might allow more than one fetch per output pulse.

 

Here is some notes to chew on. I had a MRI this AM + iodine introvenious infusion- not supposed to
have serious side effects so why do I feel rotten?
Ask away and maybe I can come up with some answers.
Printer missed the +5 V connections on top of drawing.


+ 5V
___________________________________________________________________________________________________________

 

Have you tried turning on an incandescent lamp near this thing?- you will be horrified by the results, but it's an essential thing to try.
This is why commercial light curtains never use DC light sources.

 

Thanks for the heads up Sensacell. I placed a 72 W incandescent light 2 ft facing sensors & shure enough one of detectors was over sensitive until load R was changed from 6k8 to 4k7. Back to normal operation.

 

Thanks for the heads up Sensacell. I placed a 72 W incandescent light 2 ft facing sensors & shure enough one of detectors was over sensitive until load R was changed from 6k8 to 4k7. Back to normal operation.

God help you if you ever operate this near a window!

 

I must of had help . IR curtain on a table 4 ft. from sliding glass door facing South, sun at bottom of door, 11 AM, 33 deg N.
@ 90 deg. no problem.
Emitters facing door, no problem.
Sensors facing door, door open; two sensors of 6 over ridden.
Sensors facing door, door closed; one sensor over ridden.

 

I went back to the SFH 313FA to see what went wrong _ only thing wrong is me. 'Looks like a good choice after all.

 

Amazing help thanks.


I still have these schematics:





Perhaps you could show me a final schematic of your IR curtain working prototype?

 

I think that you have it all in post # 38 & # 53 & #60.
Post # 38 shows either 7430 or 74HC30 but my protype, because I had one, uses a CD4068BE , different pinout and has both NAND & AND outputs. On solderless bread board with a LED & driver, post # 53,
on NAND output, tied all inputs hi & one at a time varied input V to check trip point between 0 & 1.
Average about 3.3 V. On inputs , adjusted R2 's so V was about .5V higher than trip point. It is a balancing act so that light leakage V out does not = a hi and normal light does = a hi.
An other possibility is to use a comparator on each photo transistor output allowing trip point to be determined, probably one common fixed V. Only need 2 IC's, 4 / IC.
I think I'm rambling so better stop.