Dashboard PCB Replacement (CJH Design)
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- icosahedron
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Re: Dashboard PCB Replacement (CJH Design)
Refer to CJH's pdf on how to mount the regulator. It must be mounted flat down on the board using the mounting hole. The PCB itself then acts as a heat sink. Mica is a good thermal conductor and an excellent electrical insulator. In this application it is not really required.
E D I T: I was wrong about the mica washer. The regulator is mounted on the ground plane of the PCB and only the solder resist will provide electrical insulation without it; a mica washer is definitely required.
E D I T: I was wrong about the mica washer. The regulator is mounted on the ground plane of the PCB and only the solder resist will provide electrical insulation without it; a mica washer is definitely required.
Last edited by icosahedron on 04 Jul 2025, 19:28, edited 1 time in total.
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Re: Dashboard PCB Replacement (CJH Design)
£4 gets you 10 heatsnks with pads and washers suitable for the TO-220 package used by the 7810 . probably get them cheaper than that.
#
Heatsink.
Which reminded me that I do need some for an application where I am pushig near 1.5A on a 7v Drop.
Cheaper
#
Heatsink.
Which reminded me that I do need some for an application where I am pushig near 1.5A on a 7v Drop.
Cheaper
TwinTurbo
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1985 1.9 DG Caravelle Autohomes Karisma
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Re: Dashboard PCB Replacement (CJH Design)
I wouldn’t place mica in the category of good thermal conductors. It’s typically about 500x poor at heat conduction as aluminium or copper. The regulator should make good thermal contact with either a small heat sink or the ground plane of the board.icosahedron wrote: ↑04 Jul 2025, 18:57 Refer to CJH's pdf on how to mount the regulator. It must be mounted flat down on the board using the mounting hole. The PCB itself then acts as a heat sink. Mica is a good thermal conductor and an excellent electrical insulator. In this application it is not really required.
Paul F Dennis
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Re: Dashboard PCB Replacement (CJH Design)
First package turned up with the "Mechanical Fit" model. It's spot on. Unforunatly the LED's I bought to restock my supplies had short legs ( seems to be a common cost saving these days to knock 5mm off a leg. So they don't sit fully home.
TwinTurbo
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- icosahedron
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Re: Dashboard PCB Replacement (CJH Design)
I fully agree with you that mica is not the best thermal conductor. The following is what I was trying to get across:PaulFDennis wrote: ↑04 Jul 2025, 19:25I wouldn’t place mica in the category of good thermal conductors. It’s typically about 500x poor at heat conduction as aluminium or copper. The regulator should make good thermal contact with either a small heat sink or the ground plane of the board.icosahedron wrote: ↑04 Jul 2025, 18:57 Refer to CJH's pdf on how to mount the regulator. It must be mounted flat down on the board using the mounting hole. The PCB itself then acts as a heat sink. Mica is a good thermal conductor and an excellent electrical insulator. In this application it is not really required.
"In electronics, mica is used to electrically isolate heat sinks from components while still allowing heat to dissipate."
Re: Dashboard PCB Replacement (CJH Design)

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Re: Dashboard PCB Replacement (CJH Design)
The Hairy Camper wrote: ↑04 Jul 2025, 10:05 Excellent progress, TT. I was given the final designs for my prototype a couple of days ago. JLCPCB are out of stock on 4 items needed to populate the board though, so I've got to sit tight until they've restocked next week. It's my first time using them though, so they've offered free assembly which is probably worth it.
Get yourself a ferrule crimper and crimps , work a lot better than plain wire with the screw terminals.
TwinTurbo
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Re: Dashboard PCB Replacement (CJH Design)
3 More Packages..

The Edge connector, there is a fault on this that I have lodged with JLC. The Design had wider tracks than the production. Even on the Gerber file on JLC website the tracks are the correct witch but something has faile din production. Waiting on a response.

The DOPS Connector. I have made a mistake on this, I deleted every other pin hole as it's 2mm pitch and the dash is 4mm pitch. I did not need to delete the hole and it just means I have to cur the pins from the 2mm Pitch connector.

1 in 3 may be right, the track size is correct on this one.


The Edge connector, there is a fault on this that I have lodged with JLC. The Design had wider tracks than the production. Even on the Gerber file on JLC website the tracks are the correct witch but something has faile din production. Waiting on a response.

The DOPS Connector. I have made a mistake on this, I deleted every other pin hole as it's 2mm pitch and the dash is 4mm pitch. I did not need to delete the hole and it just means I have to cur the pins from the 2mm Pitch connector.

1 in 3 may be right, the track size is correct on this one.

TwinTurbo
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Re: Dashboard PCB Replacement (CJH Design)
I may have time to trial fit tomorrow, but I am at the local amature theater for the next two weeks on and off doing the SFX for a production. and the weekend after that am In Barrow on Lighting for a festival. And that's aside from the day job.
TwinTurbo
1985 1.9 DG Caravelle Autohomes Karisma
1985 1.9 DG Caravelle Autohomes Karisma
Re: Dashboard PCB Replacement (CJH Design)
Loving watching this progress. I purchased a similar thing from slaughter house customs. 


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Re: Dashboard PCB Replacement (CJH Design)
There are a few designs out there from various suppliers.
TwinTurbo
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Re: Dashboard PCB Replacement (CJH Design)
Actualy it's not faulty , it was a trick of the light. It was easier to see the tracks in the photo than real life.


TwinTurbo
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Re: Dashboard PCB Replacement (CJH Design)
Progress slow this last week or so with the theatre performancees ( 1st nigt sell out and almost perfect from the tech team
) only 4 more to not F###### up .
With the mechanical fit confirmed on the LED board I need to do the same for the edge conncetor ( althoug we have seen the "Proof" ) and for the guage board.
It's then just going over the schematic 50 times and confirming it's correct for the LED board and then laying up again in the PCB design.
I have been looking at the DOPS and have a rough plan for a daughter board that will do away with the original DOPS all togerther , althought the buzzer may not be quite as authentic as the bizare VW chattering relay.

With the mechanical fit confirmed on the LED board I need to do the same for the edge conncetor ( althoug we have seen the "Proof" ) and for the guage board.
It's then just going over the schematic 50 times and confirming it's correct for the LED board and then laying up again in the PCB design.
I have been looking at the DOPS and have a rough plan for a daughter board that will do away with the original DOPS all togerther , althought the buzzer may not be quite as authentic as the bizare VW chattering relay.
TwinTurbo
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- Oren Kipnis
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Re: Dashboard PCB Replacement (CJH Design)
I follow this thread every time there is an update, and appreciate the effort put into the development.
Will be happy to purchase 2 units once the entire kit goes to batch production.
Will be happy to purchase 2 units once the entire kit goes to batch production.
1990 ex. German Army Syncro, 3 knob, AFN, M469 fully converted to 16". Camper conversion by URO CAMPER in Seville.