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I'd probably supply the wire with the board.  One end could have a pin attached to inset into the the proper DIN hole and the other end would be stripped for soldering.  

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This time around for the MK2 all assembly has to be included on the PCB or something I can source and just include.  The original F18A required me to solder all the PCB pins, JTAG header, and VGA header (and initially the jumper header as well).  I don't have the time or energy to do that on the MK2, sorry.  Finding specialized cable assemblies is a PITA, and having custom assemblies made is too expensive.  The MK2 will have a means for audio-in, but it will be up to each user to find their own way.

 

However, at the other end of things, should the DVI header PCB assembly include a 3.5mm audio jack for audio out?

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Thanks Shift838.

 

@Andrewmacattack

Yes, I have a store on my website where they will be for sale.

 

I'm actually a somewhat nervous about the MK2 right now.  I think the demand is pretty high, and the initial volume will be scary (having hundreds of boards made at a cost of thousands of dollars can be nerve-racking).  To help me not have to guess on the quantity for the first run, I will probably take a pre-order (again, via my store) and have as many boards built as necessary.  After that, like the original F18A, I will try to keep the MK2 in stock as the demand requires.

 

But, I need to get the DVI board done, get some prototype PCBs, and get through testing first.  The DVI header is *big* and will probably double the PCB size, which is not really a good thing since this is a 4-layer PCB (40% cost over a 2-layer PCB).  The DVI receptacle is expensive too, around $4.80 each, compared to the more popular video format receptacles at $1 to $2 each.  Nothing to do about that though.  At least the DVI header will be designed for panel-mounting and will have a few PCB holes to facilitate mounting in various situations.  Also, having the video receptacle off-board does also offer some protection to the MK2 itself, i.e. you won't rip the board out of the socket when you trip or yank on the video cable.

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2 hours ago, matthew180 said:

However, at the other end of things, should the DVI header PCB assembly include a 3.5mm audio jack for audio out?

 

I game for that, but that will require a D/A conversion to output audio generated in the MK2, itself, right?

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PWM in the FPGA, low-pass filter on the output pin; done it a few times, works good.  This would let you have audio out without having to use the DIN-5 cable.  Although, the internal audio-in connection would still be required, and the audio would go through two unnecessary conversions (analog to digital, and back to analog).

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One thing is certain, DVI headers are *BIG*!  And this does not have the 3.5mm audio jack on it yet.  Still debating that option.  This header board is about two-thirds the size of the MK2 itself.  Connectors are such a PITA.  At least it will be a solid panel mount.

 

fpc2dvi1.thumb.png.f6ad66cd436dfab0e2343172a2e8f578.pngfpc2dvi2.thumb.png.ef0b590280f631be9d9e6ffa80853ff4.pngfpc2dvi3.thumb.png.5b0303c7d26b4a3613dbd2d896ccf491.png

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It is important that the track lengths are consistent within each individual board, not just across the entire end to end connection. It doesn't look from these renders as if you've fallen into this trap, but I'm explicitly mentioning it, just in case you do! :P

(For the uninitiated: with HDMI and similar high frequency or differential pair signals, the tracks need to be very evenly matched in electrical length and impedance. If the design is split across two boards, each board standalone must be 'straight' as you can never be sure they will be paired with each other, or that a future board layout might shift tracks on one side around. So you have to look at the totality of the whole system. If you split the differences across the two boards so they only matched each other, and you then put the DVI header on an OTHER board, everything would go out of alignment and you'd have all kinds of subtle signal quality issues. This SUCKS. Especially if you later do a MKIII board and want to use the same header and you have to remember where you put the allowances.)

 

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Yup, all pairs de-skewed and length matched.  I am aware of the TMDS requirements for routing, but thanks for making sure.  Routing this header was a real PITA due to the pin locations in the DVI header, and took way longer than I had hoped.  Clearly this header was not made with ease of layout or integrity of the TMDS signals in mind; and if it was, I certainly don't know what those specific characteristics might be.

mk2dvi.thumb.png.a557ae5d8fc3a8827aed38049f420840.png

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Looking good Matthew 🙂 

On 8/13/2019 at 8:04 PM, matthew180 said:

I thought about that, except the extra wire will be the responsibility of the user.  You can get them with clips on both ends.  They don't make the best connection, but it is easy for people without a means to solder the wire.

 

I think to minimise the risk of damage you should supply it with a wire already soldered to the board for the audio then if the user wants to inject the audio they can strip the other end and wire it to the DIN socket themselves.

 

On 8/16/2019 at 8:21 AM, matthew180 said:

One thing is certain, DVI headers are *BIG*!  And this does not have the 3.5mm audio jack on it yet.  Still debating that option.  This header board is about two-thirds the size of the MK2 itself.  Connectors are such a PITA.  At least it will be a solid panel mount.

 

Have you considered just leaving pads available on the DVI PCB header board so we could wire our own 3.5 mm jack to the PCB:

 

10PCS 3.5MM Mini Stereo Female Panel Mount Headphone Jack Solder, Black 4 C W1R7

 

Whilst not confident enough to soldier a wire directly to the F18A board (see first quoted post above) I suspect the DVI PCB board would be easier!

 

It would mean drilling another hole although it would have the advantage of it being entirely up to the user where they mount it. Of course you could just bypass the F18A and DVI PCB header and wire the audio jack straight to the DIN socket anyway.

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