SS Lancer
Well-Known Member
Yes the old US company names are locked in our memory banks and all were better than off shore - garbage .
1974 Brain Box saves the day.
- Thread starter George Jets
- Start date
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Just info.
Working on a really large lot of stuff right now. Hope I can swing it. I am out of room I really need a 20' container for some of this stuff. Way to many sun machines right now.
SS Lancer
Well-Known Member
Old jewel I picked up !
I have two of the exact same ones. There is one from the early desotos that is a .25 ohm also that I have sold to guys in a pinch. Let me get pics of the ecu draw, amazing what is in there.
SS Lancer
Well-Known Member
Good info in a pinch one might could find one of those !
Some guys cant swing 50 on a ballast. I get it it is a lot.
Please click to expand so you can read this whole post below:
The TO-220 transistor would likely work if they properly heat-sinked it. That is what the big screw-hole is for, and you see them bolted to a thick heat-sink in every commercial product.
the small transistor they use today T0-220 is rated at 150W, the TO-3 is rated at 300W and the case is the collector.
Your small transistor heat sink should contact the metal of the cover securely to dissipate heat only, probably insulated, not used as the collector circuit anymore for safety reasons (ie. 400V potential at the case of the old ones) you can thread a hole in that heat sink, put some thermal compound on it and screw it down to the real heat sink for added thermal conductivity if your so inclined.
Just for the sake of conversation, others are saying that that small transistor heat sink should be mechanically fastened to the the ICM shell and the external heat sink to help pull the internal heat out of the chip.
The new Standard Products LX100 internal heat sink tab is sitting just inside the cover not fastened to the external heat sink. This may have actually designed in this way to keep people from getting shocked by touching the external transistor like the old ones would do. Today's Liability . . .
I would think if the new LX100 ICM interal heat sink tab was screwed to the external aluminum heat sink, that would be a big win for reliability and pulling the heat out of that internal chip thus eliminating the failure rates.
More to come . . .
Here is the new LX100 cut open again.
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SS Lancer
Well-Known Member
Yes sir on the $50 price
I been building up my collection of the mostly unwanted technology or primitive stuff
Accel nos dual points
Caps - buttons and racing points sets
I also have alot of racing point sets for single point LA distributors
I still find above US made items valuable.
Yes, this will add to my post on page #58
Yes people are saying to proper heat sink the aftermarket ICU.
Here is a hack for the Standard Products LX100 Ignition Control Module that I am considering.
Take and drill a 1/2" hole through the fake (top hat) transistor on center, then take a 1/4" drill bit through the heat sink hole that lines up with the internal heat sink tab hole.
Drilling only deep enough to get through the outer skin of the ICM, to gain access to the inner heat sink tab.
Now take a stainless steel sheet screw of proper size and lenght. Screw it though the hole and catch the hole in the inner heat sink tab, carefully snugging it up to make the inner heat sink tab and the outer heat sink as one.
Dissipating the internal heat to the ICM case and outer heat sink. Without having to cut the whole ICM case open to see what is inside like I did for this demonstration.
I think people are on to something here to get the heat out of the internal chip.
Some thoughts to add to the collective thinking on this subject.
I see in the internals of the LX100 ICM there is a piece of some tape or tape compound between the internal heat sink tab and the ICM case.
The tape is possibly a thermal conductor, or an insulation layer. Someone on here may know the purpose of that tape layer.
The tape is possibly a thermal conductor, or an insulation layer. Someone on here may know the purpose of that tape layer.
Continuing on from Post #60
@BillGrissom
@pishta
@halifaxhops
What do you guys think about the compound inside the LX100 ICM where the internal heat sink tab is pasted together with the inner skin of the ICM? Would that be a thermal transfer compound, it is hard and black, and there looks like some thermal transfer tape in there too.
If that is indeed thermal transfer compound then a person would probably not need to mechanically fasten the internal heat sink to the ICM body and external heat sink.
I would think from an assembly point of view they would drop in the board and the heat sink goes down into the thermal compound at the same time. Then they put one rivet into the installed terminals and plastic connector housing to hold it all together. Then they fill with sand with a thin layer of epoxy over all that to seal it all up.
If this is the case I am thinking that this is more thermally efficient than I thought upon my first inspection (without being bolted together), giving the the internal heat sink tab a way to transfer the internal chip heat out to the external aluminum heat sink and out then to the surrounding atmosphere to get rid of it.
What are your thoughts on this ? Could maybe even add a couple heat sink wings to the external heat sink to make it pull the heat out even better ??
@BillGrissom
@pishta
@halifaxhops
What do you guys think about the compound inside the LX100 ICM where the internal heat sink tab is pasted together with the inner skin of the ICM? Would that be a thermal transfer compound, it is hard and black, and there looks like some thermal transfer tape in there too.
If that is indeed thermal transfer compound then a person would probably not need to mechanically fasten the internal heat sink to the ICM body and external heat sink.
I would think from an assembly point of view they would drop in the board and the heat sink goes down into the thermal compound at the same time. Then they put one rivet into the installed terminals and plastic connector housing to hold it all together. Then they fill with sand with a thin layer of epoxy over all that to seal it all up.
If this is the case I am thinking that this is more thermally efficient than I thought upon my first inspection (without being bolted together), giving the the internal heat sink tab a way to transfer the internal chip heat out to the external aluminum heat sink and out then to the surrounding atmosphere to get rid of it.
What are your thoughts on this ? Could maybe even add a couple heat sink wings to the external heat sink to make it pull the heat out even better ??
lol just a few
Never enough. LOL
Semiconductor technology has changed dramatically in the last 50 years. Switching speeds are much faster. Most of the heat in a semiconductor is generated during switching. Faster switching means less heat generated, which is one reason packages have gotten a lot smaller for the same power handling capacity.
In my opinion, the Chinese replicas are likely unreliable because of the shoddy manufacturing, rather than a different transistor. On the OEM parts, the transistor was firmly and closely attached to the heat sink. In the Chinese version, it appears that the transistor is placed “close” (whatever that means) to the case with some thermal grease blobbed on. It is not mechanically attached. This method is not good for heat transfer. The power handling capability of the TO220 style (and others) transistor goes way up with a good heat sink correctly configured, which the examples are not.
The sand is an interesting twist. No doubt very cheap. I would suspect it acts as thermal storage rather that thermal dissipation. That means it would act like a heat sink until it warmed up, then it wouldn’t do anything.
In my opinion, the Chinese replicas are likely unreliable because of the shoddy manufacturing, rather than a different transistor. On the OEM parts, the transistor was firmly and closely attached to the heat sink. In the Chinese version, it appears that the transistor is placed “close” (whatever that means) to the case with some thermal grease blobbed on. It is not mechanically attached. This method is not good for heat transfer. The power handling capability of the TO220 style (and others) transistor goes way up with a good heat sink correctly configured, which the examples are not.
The sand is an interesting twist. No doubt very cheap. I would suspect it acts as thermal storage rather that thermal dissipation. That means it would act like a heat sink until it warmed up, then it wouldn’t do anything.
So it is sounding like it is still a good idea to go in and do my 2 step drilling hack and mechanically fasten the internal heat sink to the external heat sink my means of a screw fastener.
Thank You
Need to do my 1/2" hole Drill through the empty transistor top (top hat) to gain access, then 1/4" drill hole through the control module box to gain access to the internal heat sink tab with the hole in it, then self tap screw it together.
Should be able to do that being the outer heat sink has pre-aligned drill holes underneath the "Top Hat".
So only 2 drill holes to do the task and not having to open the whole case to get inside.
I would try it. Will be really interesting to see how it turns out. May not be the only problem, but it is an obvious one.
Finding a nice size machine screw here, needs to be just a bit longer. Now if I can get a tap of the same threads to gently put some threads in the internal heat sink tab hole. That should make a good fastener and heat transfer item all in one.
Thanks again, will see what I can come up with. Have to order in a couple more LX100 modules to experiment with, the nice part is they are in huge supply all over.
Yep, need to get this internal heat sink tapped for machine threads without wrecking it. Doing it from the outside without opening the case, if lucky just a 3/16" hole through the control module case for acess.
Hopefully I can just cut some thin threads into the inside of the existing hole.
Hopefully I can just cut some thin threads into the inside of the existing hole.
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pishta
I know I'm right....
The collector/heatsink is electrically hot in the circuit, it connects pin 2 to 3 and pin 2 is also the heat sink portion. The voltage is only 12V, not enough to shock you (unless its a flyback from the coil) if you are going to attach it to the heatsink directly, you will short the collector (+) to ground (-) via the heatsink unless its isolated from the case, probably not! The 'tape' you see may be mica, plastic or another insulator but your screw needs to be insulated as well from ground with a bushing, or use a nylon screw. Best bet is to allow the heatsink to be isolated from the case (on plastic isolators) and then you can run the metal screw into the collector/sink and use it as a conduit for the heat. It would work better if you actually cut a hole in the case and allowed the collector of the TO-220 to bend out to contact the isolated heatsink.
The pins 2(+4, the heatsink) and 3 are the open switch, when a small current is applied to the base (1) it allows the switch to close allowing current to flow between 2 and 3. remember 4 (heatsink) is also pin 2, they are internally strapped. The small current is supplied via the reluctor and its associated circuitry. This acts as a high speed relay, switching coil on/off up to 12,000 RPM (800 times per second) or 800Hz with a very small trigger voltage.
The pins 2(+4, the heatsink) and 3 are the open switch, when a small current is applied to the base (1) it allows the switch to close allowing current to flow between 2 and 3. remember 4 (heatsink) is also pin 2, they are internally strapped. The small current is supplied via the reluctor and its associated circuitry. This acts as a high speed relay, switching coil on/off up to 12,000 RPM (800 times per second) or 800Hz with a very small trigger voltage.
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OK good information here. I am studying these and am looking over another 4 pin module with a functioning "Top Hat" transistor. I see that the transistor is isolated by a thin plastic sheet and the attaching screws have plastic bushings around them, to keep them from shorting it out as you say.
Will open this one up tomorrow to see the inner workings.
Here is another new module available through Parts Geek that looks like it has the "Hot" working Top Hat transistor.
I like this model because I identify the working transistors as the shorter wider transistors that are mounted with the course threaded screws just like the mopar units.
Also has the insulating sheet below the first layer of the external heat sink, identifying it as Hot, a working transistor.
Would actually like to buy some of these exact models if I can find the true sellers. They are looking like they could be real good new units.
I like this model because I identify the working transistors as the shorter wider transistors that are mounted with the course threaded screws just like the mopar units.
Also has the insulating sheet below the first layer of the external heat sink, identifying it as Hot, a working transistor.
Would actually like to buy some of these exact models if I can find the true sellers. They are looking like they could be real good new units.
pishta
I know I'm right....
Yup, thats a thermally conductive insulating pad. The TO-3 had two pins plus the case to make the 3rd. The 2 pin layout was for it to fit in a common at the time tube socket. Im not sure how they even utilized the case as the 3rd pin in that application as it looks as if the entire TO-3 case (collector) is insulated? Show us the nudes tomorrow!
EDIT>> looks like one screw may be used for collector to whatever is under the case...time will tell<<
EDIT>> looks like one screw may be used for collector to whatever is under the case...time will tell<<
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OK that's cool, Thermally Conductive Insulating Pad.
Insulation for the voltage, yet conducting the heat to the Heat Sink and out.
That pad is doing 2 jobs at once, like that!
Insulation for the voltage, yet conducting the heat to the Heat Sink and out.
That pad is doing 2 jobs at once, like that!
OK here are 2 of my New Old Stock "MADE IN USA" control modules.
Looking exactly like the ones being advertised on Parts Geek as pictured here on Post #72.
Showing the Thermal Insulated Heat Transfer Pads on both of them. Identifying them as working Top Hat, hot transistors.
MADE IN USA
Looking exactly like the ones being advertised on Parts Geek as pictured here on Post #72.
Showing the Thermal Insulated Heat Transfer Pads on both of them. Identifying them as working Top Hat, hot transistors.
MADE IN USA
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