There's (3) available on eBay.Old TRANSPO ELECTRONICS STOCKNOT a standard Ford regulatorSee the cover phillips head screws? There's a pot underneath.On the reverse side there is a FIFTY AMP TO-3 power transistor on a heat sink.Inside are a couple of MR2535 avalanche rectifiers.http://www.ebay.com/itm/Transpo-F540HD-Voltage-Regulator-FORD-1G-40-65-Amps-Heavy-Duty-/151837580701?hash=item235a399d9d:g:OeQAAOSw3xJVa1M2&vxp=mtrThis is a piece of cake to use with your alternator.If I were you I would buy one to eat now and one to save for later. This unit has been out of production AND THE EBAY PRICE IS THE SAME AS WHAT I WAS PAYING FOR THEM THIRTY YEARS AGO.

MEXICOWANDERER wrote:There's (3) available on eBay.Old TRANSPO ELECTRONICS STOCKNOT a standard Ford regulator See the cover phillips head screws? There's a pot underneath.On the reverse side there is a FIFTY AMP TO-3 power transistor on a heat sink.Inside are a couple of MR2535 avalanche rectifiers.http://www.ebay.com/itm/Transpo-F540HD-Voltage-Regulator-FORD-1G-40-65-Amps-Heavy-Duty-/151837580701?hash=item235a399d9d:g:OeQAAOSw3xJVa1M2&vxp=mtrThis is a piece of cake to use with your alternator.If I were you I would buy one to eat now and one to save for later. This unit has been out of production AND THE EBAY PRICE IS THE SAME AS WHAT I WAS PAYING FOR THEM THIRTY YEARS AGO.

There are NO mistakes with url cut and paste. Someone somewhere is huffing and puffing on wacky weed.Thanks Don

Ordered one.I am assuming since it has 4 contacts that the VR's case need not be grounded?That one of the contacts is ground, one a relayed ignition on Hot, and the other two for the field?What made you decide to find this New Old Stock gem?Now I guess I got to order that trick the ECM resistor too.

The regulator case MUST BE GROUNDED on all external Ford regulators. This F540is the product of a liaison between myself and Frank Oropeza of Transpo in Agostino's restaurant in Ft Bragg in 1982. I ranted and carried on about the propensity of B circuit regulators to latch (destruction) when battery reference negative was removed from the circuit. Absolutely positively zero voltage droop from .1 amp field to 20 amps of field current. This reg is .01 stable. And it does not Laurel& Hardy if ground reference is lost.F) field to one alternator brush. The other brush must be negatively grounded to the case.S) signal from ignition switch. One of your existing field wires to a brush on the alt is a super quality ignition signal source. Extend it to the regulator S terminalI) used when an indicator light is needed - an idiot light. Leave unconnected.A) means a+ battery reference always hot. It doubles as the regulator reference voltage input and source power for the field F terminal circuit. I like the overkill this circuit with a 12-gauge power wire. Now, if you have a superb alternator to battery positive post circuit (which would mean you upgraded it) you can cheat and connect the regulator A terminal to the alternator output stud. Makes the circuit handy, and shorter - no cross compartment runs.Chop the alternator brush field terminal with dikes. I like to use 14-gauge wire here because of mechanical strength. Solder all terminals and splices. Run to a shiny clean ground.Run a 14-gauge wire from the regulator F terminal to the OTHER brush terminal on the alternator. Solder.I SOLDER A 1/4" 12 gauge ring terminal to the regulator case. Remove the irridite plating first. Gob on the solder. Use a plated bolt or wood dowel to keep the holes aligned. 12 gauge wire to the engine in harness with the F and I wires to the alternator. I like external tooth lock washers for all this.Go online. Go to eBay.SEARCH Ford External Voltage Regulator Plugs.There are two types of plugs. Both fit. One is junk.The plug you want is RED. It has a plastic bridge retaining loop that keeps the plug snapped onto the regulator. The junk one waits until heavy night time traffic, with cloudburst, then slips off the regulator terminals.The regulator and plug terminals are all cad plated. Smother them with electrolytic silicone grease, including the side where the wires enter the red regulator plug. Smother the riveted terminals beneath the reg. The soldered regulator ground wire is bullet-proof.Hope this helps. Transpo set the reg for 14.0 volts. Have a ball with the pot.BUT keep in mind the lid is metal and the stuff inside angers easily.

Okay I've read and reread your edited post a few times now.Don't let your optic nerve get stretched too much with the eye rolling of the following questions. Remember I do not have a background in this stuff. My 50/120 alternator has two field wire connections. To one of these comes a wire from the Transpo VR's "F" terminal. The other alternator field terminal stud gets a new wire run to the alternator casing ground?My existing field wires, one is Z1 system voltage on a light blue 14awg wire, the other field wire is green 14awg, it goes into the ECM. The 'trick the ECM resistor' is to be wired between these two existing wires after removal from alternator to keep the CEL/MIL light off.So I run another 14awg light blue wire from Z1 hub to the "S" terminal on the VR as my switched ignition. Any fuse needed?The Transpo VR case gets well grounded directly to Alternator casing. Mine does have a (-) stud."chop the alternator brush field terminal with dikes" WTF does this mean? Am I to be modifying the 50/120 alternator internally to get this regulator to work? I'd like to be able to disconnect the 'trick the ECM' resistor and return VR duty to the ECM if needed without removing alternator from vehicle.Ignore the idiot light terminal, done.A: battery reference always hot. I do have upgraded cable, but it might be just as easy to run a wire right to battery(+), or at least my 'common' feed on my Blueseas 1/2/both/off switch. Am Assuming this wire carries little current, can be thin?Now you know my desire to reach the VR's potentiometer from the driver's seat. I am assuming I can either drill a hole in the casing over the pot and have a non electrically conductive means to twist the pot, or perhaps I can desolder the pot and run wires in its place to a larger remotely mounted Pot. No doubt the VR is potted, what are the chances of desoldering. I did this successfully on the cheapowatt and Meanwell. But they were not potted. I'm not afraid to mount the VR where accessible for pot twiddling from driver's seat, but I'd rather have a remote Pot right next to my digital voltmeter on the dash, and the VR casing will not mount right here easily/cleanly, without looking like a big wart. I'd like to have it hidden behind dashboard. Any benefit to additional heatsinking?Kind of feeling like I am opening a can of worms just to get my voltage regulation in line with 'Ideal' desires, but I am learning. I've always hated knowing that if the VR inside the ECM goes belly up I'd have to do something like this anyway, but I was planning on using the standard Mopar external regulator, not trying to make a heavier duty Ford regulator work in its place.

LandYacht Here's Your Voltage Regulator (RUSH!)

MEXICOWANDERER
Explorer
Nov 01, 2015
2 regs would work with an ON/ON switch. But few regs are FLAT TEMPERATURE COMPENSATING

Recommendation?

Buy reg # 2 another HD

Then have a ball.

No problems with field feedback.

You will be making a Borgette
landyacht318
Explorer
Nov 03, 2015

2000 OHM 3386 - 3/8 ” Square Trimpot® Trimming Potentiometer

It is not submerged in Potting. It appears to have a plastic ring, cut to thickness of the legs placed under it. The potting bonds the backside of the Potentiometer to this plastic ring, Immobilizing it.

Shouldn't be too hard to remove it and have 3 thick legs sticking above the potting.
MEXICOWANDERER
Explorer
Nov 03, 2015
Newest old stock. Yay! They were made post 1996 until WAI boarded the Ship Of Transpo and tossed the crew overboard. Earlier models had the pot buried and this mommy has a FET output transistor because of the 2K resistor. This model of F540HD is a rare bird. It does have the TO3 mounted underneath on an aluminum heatsink plate, right?
MEXICOWANDERER
Explorer
Nov 03, 2015
WHY WORK WHEN I CAN CHEAT?

Landy, post images and specs for the magic gizmo (whe it arrives). I got better things to do than re-invent the wheel for an alternator field substitute.

DIBS on the remaining two F540HD regs. Depends on what I am quoted for the TVR 911-02 from Romaine Electric.

If I go with the AGM for the toad, I don't want the OEM ECU reg getting it's greasy fingers on it.
landyacht318
Explorer
Nov 03, 2015
Not sure about the aluminum plate below the TO-3. I can't see through the potting. If there is one it is quite thin. I suspect it is directly on the steel casing.

It does say made in China on the box.

I'll post the resistance once the 'trick the ecm' gizmo arrives.

They got me for 9$ shipping for that.
MEXICOWANDERER
Explorer
Nov 03, 2015
Turn the whole thing turtle. Now you are looking at the underneath of the regulator. Does it look like every other regulator? A boring expanse of flat aluminum plate base?
landyacht318
Explorer
Nov 03, 2015
Its flat, but it is steel with no protrusions other than the stamping's feet

I was expecting more girth. The removable lid is not magnetic, but the bathtub base is.
MEXICOWANDERER
Explorer
Nov 03, 2015
Makes for interesting reading even for non nerds. Even anti-nerds can glean information and there is enough Tech info to please pocket protector types.

http://www.nxp.com/documents/selection_guide/75017357.pdf

Ultra low Vf makes it all possible. Many of these devices have filtered down to the surplus outlet buy-em-by-the-pound level.

Let's hope Wo Fat won the battle with Ching Lee that the two point two cents price difference was worth buying the expensive spread MOSFET. Landy will be tickled.
landyacht318
Explorer
Nov 03, 2015
Wo Fat, McGarrett's evil Chinese spymaster Nemesis.

Can he be trusted?
MEXICOWANDERER
Explorer
Nov 03, 2015
Bookem Danno. Originator of the phrase "O Wo Is Me"