Sir ApexDestroyer . . . . .
Your # 22 . . . . one noteworthy and thorough response ! Kudos . . .
First . . . the response of the phone answerer-er-er at either OHD / Genie . . .whoever THE actual Sugar Daddy is being NOW . . . in not using their usual stock answer for such queries, and in stepping out on their own and wanting to aid you a bit, if you had actually expressed your hopes and aspirations to them.
Second . . . . the absolutely minimalist technical answer given . . . just as you might find in one of their brochures.
The only way 24 VAC (actually only 20) is used on this system is being fed out from the power transformer . . .shown as being the white epoxy unit of photo #1.
With 120VAC input into WHITE / RED and 20VAC is outputting as GREY / ORANGE which feeds over and into the white molex connector of photo #2.
That then feeds into the YELLOW rectangular area to 4 diodes arranged as a fullwave bridge rectifier to give in excess of 24VDC, that is filtered and stored in the BLUE axial leaded electrolytic capacitor.
( Positive and negative connections are marked. )
Within this controller board, almost ALL of the specified 1 amp of this power supply is being consumed, with only about 10-15 Ma being consumed over at the receiver board . . .at its specified operating voltage.
That travels via the three leads to the receiver board as :
GREEN wire . . . . .common ground . . . serving both the power and trigger output.
PURPLE / VIOLET *** wire . . . . ....Positive DC power to the receiver board.
BLACK wire . . . . . trigger output from the receiver .
ASIDE . . . . .
*** Someone step in and triple confirm . . . .but early day art classes and the chromaticity color diagram taught me, that when you mix the two colors of BLUE and RED you get . . . . .
VIOLET . . . . . . if the RED starts showing the dominance in the mix
PURPLE . . . . . if the BLUE starts showing the dominancwe in the mix.
Therefore I' m seeing a Purple wire, vice the LED diagrams + wire colors specified Violet.
Further confirmation . . .ones familiarity with EIA color coding bands on components, truly confirms their VIOLET color validity, versus this one shown . . . . . . being a PURPLE color.
my continuance. . . .
Now if you ONLY have dear 'ole DADS 1980's Fluke, pull it out for a full recommissioning, with a fresh battery.
THAT meter is still being 10 times the typical users first dinky DMM.
(Ask me why I have 11 and a half of them in my Fluke collection. )
Then you measure across the BLUE electrolytic to see what is being the FULL DC voltage that we start with.
It will probably have regulation circuitry or a zener diode in the inside controller board near the long white molex, looking down from the pair of 22Ω metal film power resistors, as there are some large electrolytics hidden away, down at the very bottom.
Therefore there could be a reduction, of that voltage before it gets over to the receiver board as the PURPLE wire..
For sure, when it gets over to the receiver board, there WILL be regulation downwards on the receiver board, maybe once, and for sure, in going on down to the 5VDC used by the decoder chip and the one other ancillary chip beside it..
Also on this receiver board, I certainly believe that the board WILL work with EITHER AC or DC coming into the board.
Should you have given a good close up of the 3 bare molex pins on the receiver board . . . of both component and foil sides. It should confirm that the PURPLE connection should pass to the anode of a 1N4000 family of diode, for half wave rectification to DC and then the use of the nearby radial canned electrolytic for power filtering. With VERY little filtering being needed, due to the miniscule consumption of this boards circuitry.
THEN, if you are sending in DC voltage at the PURPLE pin, it just zips right on thru the diode, after it taking the less than a volt drop of the diode.
WHAT THIS BOARDS CIRCUITRY DOES . . . . AND HOW IT RELATES TO YOUR FINAL APPLICATION . . . .
When you activate this opener with your transmitter, the end result is a timed and logic high signal coming out from your BLACK "trigger" wire and feeding over to the controller board and being routed by circuitry and steering diodes to activate a pair of relays (YELLOW STARRED units.)
The bottom pair of relays will be associated with the activation of either a door up or door down action of the 120VAC feed to the drive screw motor.
The relays have adequately rated contacts for that level of power switching of the motor and their activation coils operate on 24VDC.
You will see the two respective RED star driver transistors that are beside each of them.
The specific transistor that is in line to operate . . . in accordance to the open / closed door situation
will be taking that feeble HIGH signal from your BLACK trigger line and start conducting from collector to emitter to activate that relay to close your HEFTY relay contacts to activate door movement.
Electro-Mechanical end of travel switches stop the action, either opening or closing the door.
( Unless there being a photo sensor interrupt or door pressure sensing of an obstruction or faaaat lady.)
NO EXTRA CHARGE . . . it appears that the sole YELLOW top relay . . . is not even getting a sweat raising job on its contacts . . . which would be for the switching on of the garage light.
It's appearing like it is using two RED STAR + Yellow dot transistors in a darlington configuration, so that they will then have a fierce input impedance so that an initial charge on the IC branded electrolytic capacitor and its companion high resistance bleeder resistor will time out and let the driven relay drop the light after minutes or so . . . .plunk.
S o o o o o . . . . . Sir ApexDestroyer . . . . .(Key up Mission
ImPossible theme music )
Enter
Peter Graves . . . . .
Your mission, should you accept it. . . .
Is to have the WHOLE GDO system being powered up, so that you can meter the actual DC voltage that is being present at the receivers PURPLE power input, referenced to GREEN ground of the triple connector..
Getting a power adapter of that DC voltage and if at that 1 amp spec it would forever be one very COOOOOOL running wall wart.
Your interfacing will be the use of a miniature SPDT relay with its coil voltage rating being of the same voltage as your wall wart supply and an NPN small signal transistor, or one of the relay driver transistors from this unit.
The transistor gets wired to the relay and the coil of the relay has an 1N4007 diode across the relay coil with its bar end going to the wall wart + input.
The relay contacts that are closed, get inserted into your now totally electrically isolated +3VDC circuitry, so that there is normally closed loop continuity. You key the transmitter and the +3VDC circuit loop is opened, just as you wanted.
Thaaaaaaassssit .. . . . . .
If you have further ? s . . . . . . just call BR-549 and Junior will fetch me to our party line phone . . .iffen he can get old lady Crabtree, across the holler . . .offen the line.
PICTORIAL REFERENCING . . . .
73's de Edd
.....