MEP 805B 806B screen dim/bright tool build

Going to start on the build for a tool to lighten and darken the screens on the 5/6B's. Finally got the cable from China

I am probably going to use a waffer board to backup, the terminals are open on the back of the breakout board. The pour potting material over the whole thing to dummy (155mm) proof it.




Going to use a double throw spring loaded switch for the up/down bright and then a single throw for the on/off

If there are some smarter electronics guys out there, I am open for design improvement until I pour the potting material.

Talked with our local radio shack owner, he suggested a job box instead of waffer board and to use separate push buttons instead of a double throw. I thought it was good ideas, here is what i have so far.



Thinking i will get the test runs done tomorrow, then pouring potting epoxy so suggestions better be quick

I think i wired it correctly

I think you got good advice from the radio shack dude. Two separate push buttons seems like it is more foolproof. Don't fill it until you have done multi runs, on several differant CIM's. But all in all, looks good!!!

Thanks. I am surprised that noone else has done this. The army way of building a tool was a good way to smoke a CIM because you have a chance of getting the wrong wires out of the 100 wire loom. My build is fairly fool proof even for a dummy like me.

I only have 2 available locally, mine which doesn’t need adjusted but the other jenny is brand new, like 12 hours not a reset, its CIM is unreadable without the dash lights on. So I will tear down its plug and tape then adjust the screen

Ahahhaha, it vurks.



it will adjust to full white and full black. 40-50 button pushes from full dark to full light. I dont know if my backlight switch works or not, the sun is too bright, will check that this evening when it gets dark.

Now off to town to see if I can fix the other machine, that will make the owner very happy. He didnt know that he had a problem, whomever sold him the genny, at a premium, was not truthful at all. Seller told buyer, oh thats just how its supposed to work, liar liar pants on fire. I dont know who the seller was, but there are some other things I want to bend his ear about as well. Thats why I hate used car sales men, whatever it takes to make the sell, even if they outright lie about it.

M35A2-AZ, when this gets epoxy, it will be in the mail to you to fix yours.

Looking REAL good!

Find out who this guy is, and if he is someone who makes a living at selling gen sets, put the word out. Man, people like that need the KGB solution for their problem.

here is a video of the tool at work.

https://youtu.be/Yyv2Xf-616g

remember the mouse will not work, and the reading are not correct, this tool is for contrast only.

When verifying that the back lights are working correctly, look at both sides on the top and the bottom. There are 2 separate back lights in the CIM

Video was taken in the shadow of the shop in the shadow of a truck. In direct sunlight the screen will washout much worse at lightest contrast setting.



I did use some 1" standoffs on the bottom of the breakout board to center it in the job box

155mm said:

Going to start on the build for a tool to lighten and darken the screens on the 5/6B's. Finally got the cable from China

I am probably going to use a waffer board to backup, the terminals are open on the back of the breakout board. The pour potting material over the whole thing to dummy (155mm) proof it.

View attachment 711194View attachment 711195


Going to use a double throw spring loaded switch for the up/down bright and then a single throw for the on/off

If there are some smarter electronics guys out there, I am open for design improvement until I pour the potting material.

Click to expand...

Great job!

May I ask why you feel the need to pot this?

I am a bull in a china shop and the breakout board I didnt think was skookum enough to be wiggling around with the 100 pin hanging off the end. Dust, dirt, wham bam thank you ma'am of having to be around gunbunnies my whole green iron career. Build it 10x stronger cause some dumble dorf will use your special tool as a toothpick and jump rope.

155mm said:

I am a bull in a china shop and the breakout board I didnt think was skookum enough to be wiggling around with the 100 pin hanging off the end. Dust, dirt, wham bam thank you ma'am of having to be around gunbunnies my whole green iron career. Build it 10x stronger cause some dumble dorf will use your special tool as a toothpick and jump rope.

Click to expand...

If you feel your device has to be potted, I don't think it's cased and/or interfaced with the outside world correctly.

Yes potting may be cheap and expedient, but it just transfers stresses to other parts and prevents any future serviceability.

Potting is usually done as a security measure or thermal stabilization measure on highly temperature sensitive circuits/components.

Potting for physical damage just makes it heavy and even more likely to be used as a hammer.

Farmitall said:

Great job!

May I ask why you feel the need to pot this?

Click to expand...

I would have done the same.
1. You never need to get back into the board. No parts that need replacing.
2. The tool will not get enough use to somehow cause a broken wire in the bottom plug, so once again. Its protected.
3. If you drop it, its protected.
4. If I need to get my assistants attention, I wack him on the head with it, and its protected.

Farmitall said:

If you feel your device has to be potted, I don't think it's cased and/or interfaced with the outside world correctly.

Yes potting may be cheap and expedient, but it just transfers stresses to other parts and prevents any future serviceability.

Potting is usually done as a security measure or thermal stabilization measure on highly temperature sensitive circuits/components.

Potting for physical damage just makes it heavy and even more likely to be used as a hammer.

Click to expand...

In the military, potting is done to keep people from screwing things up, by "repairing" it. Its also done to protect the manufactures product.

155mm said:

Talked with our local radio shack owner, he suggested a job box instead of waffer board and to use separate push buttons instead of a double throw. I thought it was good ideas, here is what i have so far.

View attachment 711723View attachment 711722

Thinking i will get the test runs done tomorrow, then pouring potting epoxy so suggestions better be quick

Click to expand...

Would you consider making one to sell?

I can build one similar to the official drawing for the cable. Did one about a month ago for a customer.
PM me if interested.

I'll be building a few of these cables.
PM me if anyone is interested in getting one.

The MEP-805B / MEP-806B CIM Brightness adjustment cable/tools I'm fabricating will be ready to ship this weekend.
Feel free to PM me if anyone is interested in one.

kloppk said:

The MEP-805B / MEP-806B CIM Brightness adjustment cable/tools I'm fabricating will be ready to ship this weekend.
Feel free to PM me if anyone is interested in one.

Click to expand...

Did you build one for cjohnson?

I want to see how you built yours, post up photos

Yes, his is one of the ones being built in this batch