ProJection Notes (was Re: 502-2 ECM)

[Tom Cloud]

>Hi Tom,
>Tryed to wade through the archives to find what you have learned about
>the ECM so I can make myself a flow diagram of the unit.  Then I will
>have a better understanding of how each interact. Didn't have much luck.
>If you could clue me in I would appreciate it.  I think the choke
>setting only affects the fast idle sol. but you know what happens when
>you ass-u-me.  Making this ECM do what I want is a more appealing idea
>to me. 
>Thanks in advance for any info.  Will be in contact again shortly. 
>
>
>				Alan 
>
>Nothing cute today out of ideas

Alan, I've got the PCB parts layout in the computer (I can get
it into Gerber, but don't know about GIF or JPEG).  I've got some
of the wiring.  I've got a complete parts list.  ......  but,
as far as how it works, I only have my guesses.

Don't know what you know about eclectonics <g> so I'll spare you
that ....  lemme just tell what little I've assumed about how it
operates

 - it's a basic analog computer (that just means that it
uses analog adders, subtractors, multipliers, etc -- including
functions like log, square root, who knows ???)

 - the TPS and RPM are the primary control signals

 - the injector pulse is .7 to 1 millisecond low (injectors tied to +12)
as a constant pulse width and the rep rate varies with RPM, TPS and temp.

 - the fuel pump control line, instead of just being a DC low, is a pulse
train with a 78% (low) duty cycle of 225 microseconds with a high pulse of
50 microS.  I'm driving a relay, so it's not coming from the commutator
of the pump -- the ProJection is supposed to lower the joltage to the
pump at low rpm's, so I guess this is how they do it (sorta a "switcher")

 - the CHOKE function speeds up the engine -- otter richen the mixture,
but I'm not certain that it does

 - the ACCELERATOR PUMP is just a derivative function that richens the
mixture temporarily based on the rate-of-change of the accelerator

 - the TPS, IDLE, MIDRANGE, and POWER functions all interact with one another,
so that an adjustment on one affects the others.  I don't think the POWER
adjustment affects the other two as much as they affect each other.  IOW,
when you adjust IDLE, MIDRANGE or TPS, you'll need to touch the others.

 - set TPS so you have control with the IDLE pot.  use a vacuum gauge when
setting IDLE and MIDRANGE -- the tach doesn't provide as good info as the
vac gauge, IMO.

Tom Gruenfeld, of Holley Sales, says the connectors are available from MSD
as "weather-pack" connectors but I've been unable to get MSD to send me
a catalog.

The injectors (on mine) measured 1.6 to 1.8 ohm with my Fluke (it's been
calibrated) think they're supposed to be 2 ohm, nominally.  Part number on
them is "250R-51AA".  They have .062" diameter connector pins on top made
of hollow tubing with the wire from the injector coil inside.  I experienced
intermittent connections between the pin and the wire, so soldered them and
fixed that problem.



The connector pinout

 1 - RED   +12 V input

 2 - GRY   TPS input

 3 - GRN   fuel pump output

 4 - BLK   TPS GND

 5 - WHT   tach input

 6 - BRN   temp sensor input

 7 - YLW   fast idle solenoid output

 8 - PNK   starter solenoid input

 9 - BLU   TPS input

10 - VIO   injector output

11 - ORG   injector output

12 - BLK   GND



The parts list is below, comma delimited for spreadsheet or whatever
(the "Location" column is supposed to be all caps, but when I copied it to
text, my lower case entries reverted back to lower case   8^(  .... also,
the "Location" designator is an arbitrary grid I put on the PCB.  If
anyone's interested, I'll try to copy the PCB parts layout -- with grid --
and send it to them.

Reference Designator, Part Number, Description, Location, Notes
C-1, .01 uF, , B3, 
C-2, 2.2 uF / 25V, , A2, 
C-3, .01 uF, , A4, 
C-4, 47 pF, , B3, 
C-5, 22 uF / 35V, tantalum, B4, 
C-6, .1 uF, , B4, 
C-7, , , , 
C-8, , , , 
C-9, 47 uF, tantalum, I4, 
C-10, 10 uF, tantalum, I3, 
C-11, 10 uF, tantalum, I4, 
C-12, 4.7 uF, tantalum, I4, 
C-13, 4.7 uF, tantalum, I4, 
C-14, .01, , , 
C-15, .01, , H3, 
C-16, "47n", (.047 ??), D3, 
C-17, .01, , D3, 
C-18, "47n", (.047 ??), D2, 
C-19, "47n", (.047 ??), D3, 
C-20, "47n", (.047 ??), H3, 
C-21, "47n", (.047 ??), F2, 
C-22, 22/35, tantalum, , 
C-23, .01, , , 
C-24, "47n", (.047 ??), , 
C-25, "47n", (.047 ??), , 
C-26, "47n", (.047 ??), , 
C-27, "47n", (.047 ??), , 
C-28, , , , 
C-29, 2.2 uF/25 V, tantalum, H2, 
C-30, "22n", (.022  ??), F3, 
C-31, "22n", (.022  ??), F3, 
C-32, , , , 
C-33, .01, , , 
C-34, "47n", (.047 ??), , 
C-35, "47n", (.047 ??), E4, 
C-36, 22 uF / 35 V, tantalum, D3, 
C-37, 22 uF / 35 V, tantalum, D3, 
C-38, 1 uF, tantalum, , 
C-39, 1 uF, tantalum, , 
C-40, 1 uF, tantalum, , 
C-41, 10 uF, tantalum, , 
C-42, .01, , C1, 
C-43, 1 uF, tantalum, , 
C-44, 1 uF, tantalum, C1, 
C-45, .01, , C1, 
C-46, 2.2 uF, tantalum, C4, 
C-47, 2.2 uF, tantalum, E4, 
C-48, , , , 
C-49, 33 / 50, tantalum, , 
C-50, .1, , D4, 
C-51, .1, , E1, 
C-52, 2.2 / 25V, tantalum, E1, 
D-1, , , , 
D-2, , , , 
D-3, , , , 
D-4, , , , 
D-5, , , , 
D-6, , , , 
D-7, , , , 
D-8, , , , 
D-9, , , , 
D-10, , , , 
D-11, , , , 
D-12, , , , 
D-13, 1N4004, , C4, 
D-14, , , , 
D-15, , , , 
D-16, , , , 
D-17, , , , 
D-18, 1N4004, , , 
D-19, , , , 
D-20, GP30KGI9404, (looks like 3A diode), , 
D-21, 1N4004, , , 
D-22, GP30KGI9404, (looks like 3A diode), , 
D-23, , , , 
D-24, , , , 
D-25, 1N4004, , , 
PT-1, 100k pot, , A1, Accelerator Pump
PT-2, 100k pot, , A3, Mid-Range
PT-3, 100k pot, , A4, Power
PT-4, 100k pot, , A3, Idle
PT-5, 100k pot, , A1, Choke
Q-1, 2N2222A, , , 
Q-2, 2N2222A, , , 
Q-3, , , , 
Q-4, , , , 
Q-5, , , , 
Q-6, , , , 
Q-7, , , , 
Q-8, , , , 
Q-9, , , , 
Q-10, , , , 
Q-11, 2N2222A, , , 
Q-12, 2N2222A, , , 
Q-13, 2N2222A, , , 
Q-14, 2N2222A, , , 
Q-15, , , , 
Q-16, , , , 
Q-17, , , F1, 
Q-18, , , , 
Q-19, , , , 
Q-20, , , , 
Q-21, , , , 
Q-22, , , , 
Q-23, 2N2222A, , , 
Q-24, 2N2222A, , , 
Q-25, 2N2222A, , A1, 
Q-26, 2N2907A, , A1, 
Q-27, 2N2907A, , A2, 
Q-28, , , A2, 
Q-29, , , A2, 
Q-30, 2N2907A, , C1, 
Q-31, 2N2222A, , , 
Q-32, MJE-295, , D1, 
Q-33, , , E1, 
Q-34, MTP-305, , E1, 
Q-35, MJE-295, , , 
R-1, 1k, , B3, 
R-2, 162k 1%, , , 
R-3, 300k  1% , , , 
R-4, 1k   1%, , , 
R-5, 100K, , , 
R-6, 10K, , , 
R-7, 47K, , , 
R-8, 10K 1%, , , 
R-9, 10K, , B3, 
R-10, 10k, , B3, 
R-11, 16.2k 1%, , , 
R-12, 60.4k 1%, , , 
R-13, 20k 1%, , , 
R-14, 10k 1%, , , 
R-15, 10k, , , 
R-16, 30k 1%, , , 
R-17, 16.2k 1%, , , 
R-18, 10k, , , 
R-19, 20k 1%, , , 
R-20, 1k, , , 
R-21, 16.2k 1%, , , 
R-22, 10k, , , 
R-23, 10k, , , 
R-24, 10k, , , 
R-25, 10k, , , 
R-26, 10k, , , 
R-27, 4.12k 1%, , H4, 
R-28, 2k 1%, , , 
R-29, 1k 1%, , H4, 
R-30, 4.99k 1%, , H4, 
R-31, 6.81k 1%, , , 
R-32, 1M, , , 
R-33, 100k, , , 
R-34, 24.9k 1%, , , 
R-35, 49.9k 1%, , , 
R-36, 30.1k 1%, , H4, 
R-37, 1k 1%, , , 
R-38, 300k, , , 
R-39, 160k, , , 
R-40, 1k, , , 
R-41, 10k, , , 
R-42, 100k, , , 
R-43, 100k, , , 
R-44, 1.2k, 1%, , , 
R-45, 15k, , , 
R-46, 130k 1%, , , 
R-47, 1M, , , 
R-48, 200k, , , 
R-49, 300k, , F2, 
R-50, 300k, , F2, 
R-51, 20k 1%, , F2, 
R-52, 64.1k 1%, , , 
R-53, 47 ohms, , F2, 
R-54, 20k, , , 
R-55, 10k, , , 
R-56, 2k, , , 
R-57, 2k, , , 
R-58, 10k, , , 
R-59, 1k, , , 
R-60-A, 2k 1%, , , 
R-60-B, 3.01k 1%, , , 
R-61, 1M, , F4, 
R-62, 300k, , F3, 
R-63, 300k, , , 
R-64-A, 470k, , , 
R-64-B, 560k, , , 
R-65, 300k, , , 
R-66, 300k, , , 
R-67, 300k, , , 
R-68-A, 150k, , F4, 
R-68-B, 200k 1%, , F4, 
R-69, 300k, , H3, 
R-70, 300k, , H3, 
R-71, 100k, , F2, 
R-72, 110k, , F2, 
R-73, 47k, , F2, 
R-74, 100k, , f2, 
R-75, 10k, , , 
R-76, 100k, , , 
R-77, 10k, , , 
R-78, 100k, , f1, 
R-79, 47k, , , 
R-80, 10k, , f2, 
R-81, 10k, , e3, 
R-82, 100k 1%, , e2, 
R-83, 100k 1%, , e2, 
R-84, 100k 1%, , e2, 
R-85, 100k 1%, , e3, 
R-86, 200k 1%, , f3, 
R-87, 200k 1%, , e3, 
R-88, 6.19k 1%, , f3, 
R-89, 10k, , , 
R-90, 10k, , , 
R-91, 10k, , , 
R-92, 10k, , , 
R-93, (clipped out), , e2, 
R-94, 10k, , , 
R-95, 10k, , , 
R-96, 1M, , , 
R-97, 100k, , , 
R-98, 10k, , , 
R-99, 20k, , , 
R-100, 2M, , , 
R-101, 31.6k 1%, , , 
R-102, 100k, , , 
R-103, 200k, , , 
R-104, 33k, , , 
R-105, 1k, , , 
R-106, 10k, , , 
R-107, 1M, , , 
R-108, 10k, , , 
R-109, 10k, , , 
R-110, 10k, , , 
R-111, 1M, , , 
R-112, 100k, , , 
R-113, 33k, , , 
R-114, 33k, , , 
R-115, 33k, , c1, 
R-116, 12k, , , 
R-117, 100k, , , 
R-118, 3.9k, , , 
R-119, 3.9k, , , 
R-120, 1k, , , 
R-121, 15k, , , 
R-122, 1k   1%, , , 
R-123, 4.7k, , c1, 
R-124, 1k  1%, , , 
R-125, 100k  1%, , , 
R-126, 10k  1%, , , 
R-127, 604k  1%, , , 
R-128, 10k 1%, , c1, 
R-129, 21k 1%, , C1, 
R-130, 1k 1%, , , 
R-131, 1k 1%, , , 
R-132, 270 ohms, , , 
R-133, 100k 1%, , , 
R-134, 10k, , , 
R-135, 10k, , , 
R-136, 2k 1%, , , 
R-137, 390 ohm, 1/2 w, , 
R-138, , , , 
R-139, 100 ohms, , d4, 
R-140, 10k, , , 
R-141, 390 ohms, 1/2 w, , 
R-142, 10 ohms, , , 
R-143, 20k, , , 
R-144, 10k, , , 
R-145, 750k, , , 
R-146, 10k, , h4, 
R-147, 10k 1%, , , 
R-148, (clipped out), , e2, 
R-149, 4.7M, , , 
R-150, 20k, , , 
R-151, 64.9k 1%, , b1, 
R-152, 1k 1%, , b1, 
R-153, 2.2M, , b1, 
R-154, 750k, , b1, 
R-155, , , , 
R-156, 470k, , , 
R-157, 100k 1%, , , 
U-1, CA-3240E, wide-band op-amp, , dual op-amp (Harris)
U-2, , , , 
U-3, RC-4200, analog multiplier, , (Raytheon)
U-4, LM-301-AN, , b3, 
U-5, RC-4200, analog multiplier, , (Raytheon)
U-6, LF-398N, , , sample and hold
U-7, CA-3290E, , , dual Bi-MOS op-amp (Harris)
U-8, MD-14046BCP, PLL, , phase locked loop
U-9, CA-3240E, wide-band op-amp, , dual op-amp (Harris)
U-10, LM-2917N-8, F - V converter, , 
U-11, 7660 CPA, , , (Harris)
U-12, CA-3240E, wide-band op-amp, , dual op-amp (Harris)
U-13, CA-3240E, wide-band op-amp, , dual op-amp (Harris)
U-14, CA-3290E, , , dual Bi-MOS op-amp (Harris)
U-15, CA-3290E, , , dual Bi-MOS op-amp (Harris)
U-16, 78L05-ACZ, volt. regulator - 5 volt, , 
U-17, LM-2930T-8, Voltage Reg - 8 volt, E1, low-volt dropout
U-18, CS-453 / MC3484S4-2, Injector Driver,, 4.4 A peak current (see Motorola MC3484S4-2)
U-19, CS-453 / MC3484S4-2, Injector Driver,, 4.4 A peak current (see Motorola MC3484S4-2)




There, I think you know as much -- or more -- about the 502 as I do

Tom Cloud

   If there was a funeral at night, would all the cars drive
    with their headlights off?