Stop in for a cup of coffee

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Well, I did something spontaneous this evening.

I signed up for singing lessons.
I went with my friend to the house of a piano, chelo, and vocals teacher. This lady is pretty much a retired pro, who is having money problems so she is taking students at her house.

My friend signed up for chelo lessons and the lady thought I was there to sign up for something too. I told her i was only there for the ride.

I saw what she could do and was kinda talked into it by my friend
 
Rainy Day Auto said:
Well, I did something spontaneous this evening.

I signed up for singing lessons.
I went with my friend to the house of a piano, chelo, and vocals teacher. This lady is pretty much a retired pro, who is having money problems so she is taking students at her house.

My friend signed up for chelo lessons and the lady thought I was there to sign up for something too. I told her i was only there for the ride.

I saw what she could do and was kinda talked into it by my friend
Click to expand...
So you can sing me love songs now?
 
Getting further into the dig. I have discovered that the smaller components are almost entirely encased in the insulating RTV and only the larger ones are in half of each.

I took two similar sized pieces of each layer and allowed them to equilibrate to a fixed temperature heat plate at about 125*. The RTV warmed up quicker (insulator) and the silica mix layer got hotter (higher heat capacity). The RTV layer was only half as warm as the silica layer.

When both were placed on the room temperature aluminum heat sink plate, they both cooled down at about the same rate but the silica layer got cooler a little quicker.

This means the silica layer has higher heat capacity (holds more heat) but sheds it faster than the RTV layer (higher heat conduction). This results in a more extreme thermal cycle taxing the components.

This is a bad combination for a circuit board. The smaller components are encased in an isulating layer that won’t let them shed heat and the larger components are encased in half that and half in a layer that holds more heat before it sheds it. Add to that the external aluminum heat sink is at the opposite end of the case from where the heat is being generated making it useless.

No wonder these things fry quickly.

80BEBCCD-7BB7-4C30-B6C5-758168BA9495.jpeg
 
Rainy Day Auto said:
Well, I did something spontaneous this evening.

I signed up for singing lessons.
I went with my friend to the house of a piano, chelo, and vocals teacher. This lady is pretty much a retired pro, who is having money problems so she is taking students at her house.

My friend signed up for chelo lessons and the lady thought I was there to sign up for something too. I told her i was only there for the ride.

I saw what she could do and was kinda talked into it by my friend
Click to expand...
I should probably do that as well but I have too much to do. When I lead at Church I usually work on songs on the boat on my banjo, practice at home on my acoustic guitar and the try and do the hardest, sing while playing bass. Comes out good most of the time but there are just some songs that I need a guitar or banjo in hand to sing or I cant do it.
 
Ddaddy said:
Getting further into the dig. I have discovered that the smaller components are almost entirely encased in the insulating RTV and only the larger ones are in half of each.

I took two similar sized pieces of each layer and allowed them to equilibrate to a fixed temperature heat plate at about 125*. The RTV warmed up quicker (insulator) and the silica mix layer got hotter (higher heat capacity). The RTV layer was only half as warm as the silica layer.

When both were placed on the room temperature aluminum heat sink plate, they both cooled down at about the same rate but the silica layer got cooler a little quicker.

This means the silica layer has higher heat capacity (holds more heat) but sheds it faster than the RTV layer (higher heat conduction). This results in a more extreme thermal cycle taxing the components.

This is a bad combination for a circuit board. The smaller components are encased in an isulating layer that won’t let them shed heat and the larger components are encased in half that and half in a layer that holds more heat before it sheds it. Add to that the external aluminum heat sink is at the opposite end of the case from where the heat is being generated making it useless.

No wonder these things fry quickly.

View attachment 1715415277
Click to expand...
Probably used the sand mix to keep the board from dropping to the bottom of the tray with little consideration for thermal properties
 
zkx14 said:
Probably used the sand mix to keep the board from dropping to the bottom of the tray with little consideration for thermal properties
Click to expand...
It sure does seem that way. An electronic circuit board with these conditions has little chance of surviving very long. No wonder it died after only 200 miles of run. Add in that the hot engine bay is on the heat shedding side and it had nearly no chance at all.
 
So put together the cases with the wiring and let the person buying the case provide thier own hei module.
 
I am about to place an order with wish dot com.

They have some insanely good stuff for low prices, but I have a strange suspicion this stuff is coming from China :eek:
 
Ddaddy said:
Getting further into the dig. I have discovered that the smaller components are almost entirely encased in the insulating RTV and only the larger ones are in half of each.

I took two similar sized pieces of each layer and allowed them to equilibrate to a fixed temperature heat plate at about 125*. The RTV warmed up quicker (insulator) and the silica mix layer got hotter (higher heat capacity). The RTV layer was only half as warm as the silica layer.

When both were placed on the room temperature aluminum heat sink plate, they both cooled down at about the same rate but the silica layer got cooler a little quicker.

This means the silica layer has higher heat capacity (holds more heat) but sheds it faster than the RTV layer (higher heat conduction). This results in a more extreme thermal cycle taxing the components.

This is a bad combination for a circuit board. The smaller components are encased in an isulating layer that won’t let them shed heat and the larger components are encased in half that and half in a layer that holds more heat before it sheds it. Add to that the external aluminum heat sink is at the opposite end of the case from where the heat is being generated making it useless.

No wonder these things fry quickly.

View attachment 1715415277
Click to expand...
That is what I said way back there!!!^^^^^^^^^that transistor had no chance...
 
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I haven't said much about this, but I may have been given a good opportunity. Please add me to your prayer list. I will let yall know in a week or two after I see how it works out.
 
Well, I blew off work enough for today tearing apart this ECU. Tomorrow I need to be full time on the ball. Several meetings and a boat load of other stuff I need to do. At least I can still work from Home for it. Things are coming to a head there, they owe me a lot of money ($25k) and if I don’t get my payment soon, I am resigning. In the mean time, I intend to show them my value fully so that if I resign it will be exceptionally painful for them. I’m going to advance a bunch of stuff and then stop dead in my tracks. Pay me or I leave and won’t tell you anything to let you pick up the pieces...and it will cost you double if you ask me to do it afterward.

See you guys tomorrow night. Sleep time now.
 
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