H8 Tear down to check the new backplane.

[Norberto Collado]

Here are some pictures on the H8 chassis tear down process and to check the hole alignment to install the BP screws.

 

There is rust inside the chassis. What chemical I can use to remove the rust before re-painting the inside of the chassis for better protection?

 

Tear down:

 

New H8 backplane smaller than the old one??? Will it fit?

 

 

New H8 Backplane installed: No shorts from +8V to ground after installing screws.

 

 

Only one hole off, but still can install the screw. I just found out that the new H8 Backplane is longer than the original. Will fix for production.

 

 

Norberto

[Norberto Collado]

The ATX Mini Power Supply fits nicely and the fan covers the transformer hole. No need for a fan guard. This is the final solution and will re-attached the cover for the 110V AC to keep the inside of the H8 safe. I will keep using the original H8 ON/Off switch to control AC ON/OFF to the Power supply. Will replace the fuse with a momentary switch to control DC ON/OFF. I still need to figure out where to install another switch to be able to reset second CPU in dual configuration or perhaps use the SSI board to reset the second CPU board. Any feedback appreciated.

 

Now we have more space on the back of the H8 chassis for future expansion and the H8 chassis is not that heavy as before due to the weight of the transformer.

 

 

Norberto

 

[Glenn Roberts]

This pretty much mirrors my experience building Rusty.  It’s been my rock solid go to system all these years.  Lightweight and cool running. 

As for removing rust I recommend steel wool and good old elbow grease. I think I painted mine with satin black rustoleum

Sent from my iPad

On Jul 31, 2021, at 8:25 PM, Norberto Collado <norberto...@koyado.com> wrote:



The ATX Mini Power Supply fits nicely and the fan covers the transformer hole. No need for a fan guard. This is the final solution and will re-attached the cover for the 110V AC to keep the inside of the H8 safe. I will keep using the original H8 ON/Off switch to control AC ON/OFF to the Power supply. Will replace the fuse with a momentary switch to control DC ON/OFF. I still need to figure out where to install another switch to be able to reset second CPU in dual configuration or perhaps use the SSI board to reset the second CPU board. Any feedback appreciated.

 

Now we have more space on the back of the H8 chassis for future expansion and the H8 chassis is not that heavy as before due to the weight of the transformer.

 

<image001.jpg>

 

Norberto

 

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[Steven Feinsmith]

NO WAY! never use steel wool!!!! Regardless of any kind of abrasive materials on PCB. During the old days, there was NO solder masking. I heard some people try to polish gold fingers from the PCB. It will ruin easily because of very thin gold plating. In the past, four vintage boards had ruined gold plates on fingers. I had to use chemicals to remove the damaged gold. After several steps then, use electroplating to restore gold on fingers. It was a successful procedure. The traces on the vintage PCB were copper. That is what it needs to be careful to clean with the chemical without destroying it. When the technology was used, the solder mask solved many PCB problems and made it have a long life. During my old days, Many television printed circuit boards had no solder mask. The early computers did not have it. They had problems with the printed circuit, developed oxidation, and ruined it.
Once you get oxidation or/and corrosive on the board. It was DONE! The only way to clone and make a modern type of PCB.

Steven

To view this discussion on the web visit https://groups.google.com/d/msgid/sebhc/642FDB92-CA95-4A4C-B4F1-2565ABD23C98%40gmail.com.

[Mark Garlanger]

Steven, 

The steel wool is not for the boards, it was for the chassis. 

Mark

To view this discussion on the web visit https://groups.google.com/d/msgid/sebhc/CAGJMgmVdCjG5%2B%3DEVBmM_gVqSPLrcd1Z%3Djrb2HvisiJk%3Dkt%3Dp6A%40mail.gmail.com.

[glenn.f...@gmail.com]

Correct. Thanks for clarifying Mark.  I was responding to two emails at once (the other email Norberto sent asked how to remove rust from the metal chassis)…

 

• Glenn

To view this discussion on the web visit https://groups.google.com/d/msgid/sebhc/CAAjkm79O4TuugjMfnZdUhE4OROm-UXosxZ-aJvPXVudq1A4i7w%40mail.gmail.com.

[Norberto Collado]

Thanks and my way to the HW store to get the parts!

 

Norberto

 

From: "se...@googlegroups.com" <se...@googlegroups.com> on behalf of Glenn Roberts <glenn.f...@gmail.com>
Reply-To: "se...@googlegroups.com" <se...@googlegroups.com>
Date: Saturday, July 31, 2021 at 6:06 PM
To: "se...@googlegroups.com" <se...@googlegroups.com>
Subject: Re: [sebhc] H8 Tear down to check the new backplane.

 

This pretty much mirrors my experience building Rusty.  It’s been my rock solid go to system all these years.  Lightweight and cool running. 

To view this discussion on the web visit https://groups.google.com/d/msgid/sebhc/642FDB92-CA95-4A4C-B4F1-2565ABD23C98%40gmail.com.

[Les Bird]

Glad to see my PC power supply feature for the motherboard is coming in handy and extending the life of the H8. New design looks good Norberto. And yes, amazing how much lighter the H8 is without the transformer.

Les

On Saturday, July 31, 2021, 08:25:51 PM EDT, Norberto Collado <norberto...@koyado.com> wrote:

The ATX Mini Power Supply fits nicely and the fan covers the transformer hole. No need for a fan guard. This is the final solution and will re-attached the cover for the 110V AC to keep the inside of the H8 safe. I will keep using the original H8 ON/Off switch to control AC ON/OFF to the Power supply. Will replace the fuse with a momentary switch to control DC ON/OFF. I still need to figure out where to install another switch to be able to reset second CPU in dual configuration or perhaps use the SSI board to reset the second CPU board. Any feedback appreciated.

 

Now we have more space on the back of the H8 chassis for future expansion and the H8 chassis is not that heavy as before due to the weight of the transformer.

 

 

Norberto

 

[Norberto Collado]

Les,

 

Agreed and thank you for creating the “H8-H200” project, which has been the inspiration for the upgrades. That was a lot of work for you to do in such short time.

 

As the H8 chassis is all dis-assembled and my son is out of school, he decided to start building the H8 chassis using his CAD tools. In just a few hrs.’ he already completed the side panels. Tomorrow he will do the chassis and then he will add the provided feedback.

 

Here is what we did today:

 

H8 Chassis with internal rust. I do not know why Heath did not paint the inside of the chassis to avoid such rust.

 

Tools to remove rust:

 

H8 Chassis – Rust removed:

 

H8 Chassis Painted: I just painted the internal chassis. Did not paint the exterior.

 

New H8-Chassis in CAD: WIP

 

 

Norberto

 

From: "se...@googlegroups.com" <se...@googlegroups.com> on behalf of Les Bird <les...@bellsouth.net>
Reply-To: "se...@googlegroups.com" <se...@googlegroups.com>
Date: Sunday, August 1, 2021 at 6:39 PM
To: "se...@googlegroups.com" <se...@googlegroups.com>
Subject: Re: [sebhc] H8 Tear down to check the new backplane.

 

Glad to see my PC power supply feature for the motherboard is coming in handy and extending the life of the H8. New design looks good Norberto. And yes, amazing how much lighter the H8 is without the transformer.

 

Les

 

 

.

[Steven Feinsmith]

It looks good to me as the first step to duplicate the original H8 chassis. I like to call them "Heathkit H-8, Second Generation".

Take care,

Steven

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[Norberto Collado]

During the rust cleaning process the fastener that holds the screw for the front panel top cover came out. I’m guessing it was soldered by Heath supplier, but it came out. I think this was a defect by their supplier. What tool I need to fix this issue to be able to attached the front panel cover underneath screw? Is the same one used on the Heath card mount heatsink bracket, I think.

 

Issue:

 

 

[Glenn Roberts]

Nice job. Great to see your son’s cad/cam capture of the side panels (a chip off the old block). Any thoughts on where we could get some prototypes manufactured? The most interesting could be clear acrylic. Might have to tweak the design a bit for different materials (e.g. strengthen around screw holes).

I would like to make wooden side panels. Can you share the blueprints with exact dimensions labeled (especially screw holes)? That’s what I’ve been lacking.

The new design with PC power runs so cool I don’t think you need a vented top anymore (power supply fan and holes in the metal cabinet provide sufficient ventilation). This opens up  the possibility for a clear Plexiglas top if we can figure out how to fabricate one.

If Les’ design was the H8-2000 then perhaps this evolved version is the H8-2020!

Sent from my iPad

On Aug 2, 2021, at 12:10 AM, Norberto Collado <norberto...@koyado.com> wrote:



Les,

 

Agreed and thank you for creating the “H8-H200” project, which has been the inspiration for the upgrades. That was a lot of work for you to do in such short time.

 

As the H8 chassis is all dis-assembled and my son is out of school, he decided to start building the H8 chassis using his CAD tools. In just a few hrs.’ he already completed the side panels. Tomorrow he will do the chassis and then he will add the provided feedback.

 

Here is what we did today:

 

H8 Chassis with internal rust. I do not know why Heath did not paint the inside of the chassis to avoid such rust.

<image001.jpg>

 

Tools to remove rust:

<image002.jpg>

 

H8 Chassis – Rust removed:

<image003.jpg>

 

H8 Chassis Painted: I just painted the internal chassis. Did not paint the exterior.

<image004.jpg>

 

New H8-Chassis in CAD: WIP

 

<image005.jpg>

 

Norberto

 

From: "se...@googlegroups.com" <se...@googlegroups.com> on behalf of Les Bird <les...@bellsouth.net>
Reply-To: "se...@googlegroups.com" <se...@googlegroups.com>
Date: Sunday, August 1, 2021 at 6:39 PM
To: "se...@googlegroups.com" <se...@googlegroups.com>
Subject: Re: [sebhc] H8 Tear down to check the new backplane.

 

Glad to see my PC power supply feature for the motherboard is coming in handy and extending the life of the H8. New design looks good Norberto. And yes, amazing how much lighter the H8 is without the transformer.

 

Les

 

 

.

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<mime-attachment>

[Glenn Roberts]

The part is called a self-clinching nut

https://www.biscoind.com/pem-pennengineering-clss-032-1/p?idsku=8801590&gclid=CjwKCAjwr56IBhAvEiwA1fuqGvdyyXJd6kH7QtvXN-PP1AgbkMO27iTNyZ_4ZrfHLFMGqd9dTrJ-4BoCWWgQAvD_BwE

It was pressed into the hole at the time of manufacture. The hole may now be too distorted to accept a new nut but you could give it a try. You might be able to press it into place with a ViseGrip tool. Perhaps reinforce it with epoxy. I’m dubious about using solder but if you did you’d certainly need a high wattage iron. All of the screws are #6 32 threads per inch.

Sent from my iPad

On Aug 2, 2021, at 3:02 AM, Norberto Collado <norberto...@koyado.com> wrote:



During the rust cleaning process the fastener that holds the screw for the front panel top cover came out. I’m guessing it was soldered by Heath supplier, but it came out. I think this was a defect by their supplier. What tool I need to fix this issue to be able to attached the front panel cover underneath screw? Is the same one used on the Heath card mount heatsink bracket, I think.

 

Issue:

 

<image001.jpg>

 

<image002.jpg>

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[Glenn Roberts]

P.s. this might be best turned over to a competent machine shop. I think they could easily fix it. Perhaps braze on a new nut if the press fit doesn’t work…

Sent from my iPad

On Aug 2, 2021, at 6:19 AM, Glenn Roberts <glenn.f...@gmail.com> wrote:

The part is called a self-clinching nut

[norberto.collado koyado.com]

Thanks for the feedback and now I know what I'm looking for. I see the #6-32 self-clinch part in Amazon, but not the tool.  

https://www.amazon.com/gp/product/B08XYLQ9FC/ref=ox_sc_saved_title_1?smid=A1THAZDOWP300U&psc=1

Let me see if a ViseGrip tool can do the job.

Norberto

---

From: se...@googlegroups.com <se...@googlegroups.com> on behalf of Glenn Roberts <glenn.f...@gmail.com>
Sent: Monday, August 2, 2021 4:56 AM

To: <se...@googlegroups.com> <se...@googlegroups.com>
Subject: Re: [sebhc] H8 Tear down to check the new backplane.

To view this discussion on the web visit https://groups.google.com/d/msgid/sebhc/75A76753-27B2-4AEA-B8C9-DD158702D335%40gmail.com.

[Steven Feinsmith]

Hi Norberto,

You do not need a tool for this one. When you insert the self-clinch nut, you need a washer and screw, and it will "clinch" into the metal sheet. If you prefer to use tools for clinching purposes. Here is:

https://www.dontwasteyourmoney.com/best-rivet-nut-tool/

I hope this works for you...

Steven

To view this discussion on the web visit https://groups.google.com/d/msgid/sebhc/SN6PR01MB3855DC81A843D16E17F975C6F7EF9%40SN6PR01MB3855.prod.exchangelabs.com.

[norberto.collado koyado.com]

Thank you and a much simpler solution. There is a HW store next to me, and I will check it out this evening and hopefully they have the #6-32 self-clinch part.

Norberto

---

From: se...@googlegroups.com <se...@googlegroups.com> on behalf of Steven Feinsmith <steven.f...@gmail.com>
Sent: Monday, August 2, 2021 11:58 AM

To view this discussion on the web visit https://groups.google.com/d/msgid/sebhc/CAGJMgmWiuVk8iagm3tA62tp7F9KqL%3DG6H3QMPjzm9ER%2B539VsA%40mail.gmail.com.

[norberto.collado koyado.com]

I cannot buy locally, so I order from Amazon a bag. They should be in by tomorrow to start the assembly process again.

Chassis is painted only in the inside with flat black to eliminated/contained as must rust as possible.

Norberto

[Glenn Roberts]

You may have to reduce the diameter of the hole slightly to give the new nut sufficient purchase to hold. Perhaps tamp it a bit using a hammer and with something solid underneath to flatten out the sheet metal a bit around the hole.

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[norberto.collado koyado.com]

Good idea!

---

From: se...@googlegroups.com <se...@googlegroups.com> on behalf of Glenn Roberts <glenn.f...@gmail.com>

Sent: Tuesday, August 3, 2021 11:35 AM

To: <se...@googlegroups.com> <se...@googlegroups.com>
Subject: Re: [sebhc] H8 Tear down to check the new backplane.

To view this discussion on the web visit https://groups.google.com/d/msgid/sebhc/CACkv5mBDwOVmCrSBqOkJQBda2nwVpGkmq4PYZFOrCCRDgj%3DR0Q%40mail.gmail.com.

[Norberto Collado]

I received today the #6-32 self-clinch part and did try all possible methods to clinch the part into the metal. No matter how hard even hammering the part in, it does not want to go in. It requires a lot of force to clinch such part into the metal. I need a very powerful tool to do this as the case of the H8 is not aluminum and it is hard steel. Perhaps  a HALF TON Power Press will do as this one.

 

 

I will clean up the hole with the steel tool and use Gorilla glue or epoxy to keep the part secure into the chassis. I think this should do it. Then repaint again.

 

Thanks for all the feedback.

 

Norberto

 

 

From: "norberto.collado koyado.com" <norberto...@koyado.com>
Date: Tuesday, August 3, 2021 at 11:39 AM
To: "se...@googlegroups.com" <se...@googlegroups.com>
Subject: Re: [sebhc] H8 Tear down to check the new backplane.

 

Good idea!

 

---

From: se...@googlegroups.com <se...@googlegroups.com> on behalf of Glenn Roberts <glenn.f...@gmail.com>
Sent: Tuesday, August 3, 2021 11:35 AM
To: <se...@googlegroups.com> <se...@googlegroups.com>
Subject: Re: [sebhc] H8 Tear down to check the new backplane.

 

You may have to reduce the diameter of the hole slightly to give the new nut sufficient purchase to hold. Perhaps tamp it a bit using a hammer and with something solid underneath to flatten out the sheet metal a bit around the hole.

.

[Glenn Roberts]

Wow. Well you tried. Yes I’m sure a press of some sort was used at the factory. Again, the best way to effect this repair is to find a machine shop…

Sent from my iPad

On Aug 5, 2021, at 1:27 AM, Norberto Collado <norberto...@koyado.com> wrote:



I received today the #6-32 self-clinch part and did try all possible methods to clinch the part into the metal. No matter how hard even hammering the part in, it does not want to go in. It requires a lot of force to clinch such part into the metal. I need a very powerful tool to do this as the case of the H8 is not aluminum and it is hard steel. Perhaps  a HALF TON Power Press will do as this one.

 

<image001.jpg>

 

I will clean up the hole with the steel tool and use Gorilla glue or epoxy to keep the part secure into the chassis. I think this should do it. Then repaint again.

 

Thanks for all the feedback.

 

Norberto

 

 

From: "norberto.collado koyado.com" <norberto...@koyado.com>
Date: Tuesday, August 3, 2021 at 11:39 AM
To: "se...@googlegroups.com" <se...@googlegroups.com>
Subject: Re: [sebhc] H8 Tear down to check the new backplane.

 

Good idea!

 

---

From: se...@googlegroups.com <se...@googlegroups.com> on behalf of Glenn Roberts <glenn.f...@gmail.com>
Sent: Tuesday, August 3, 2021 11:35 AM
To: <se...@googlegroups.com> <se...@googlegroups.com>
Subject: Re: [sebhc] H8 Tear down to check the new backplane.

 

You may have to reduce the diameter of the hole slightly to give the new nut sufficient purchase to hold. Perhaps tamp it a bit using a hammer and with something solid underneath to flatten out the sheet metal a bit around the hole.

.

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[Paul Birkel]

FWIW, if a filleted epoxy of the current threaded part into place doesn’t hold then you might consider getting a J-style clip-on nut and trimming off the back-end of the J – leaving two tabs that ought to give you better adhesion and control.  Something like this:

 

To view this discussion on the web visit https://groups.google.com/d/msgid/sebhc/7596626F-251B-46CD-B183-32F7E6F8CB52%40gmail.com.

[geneb]

On Thu, 5 Aug 2021, Glenn Roberts wrote:

>> On Aug 5, 2021, at 1:27 AM, Norberto Collado <norberto...@koyado.com> wrote:
>>
>> I received today the #6-32 self-clinch part and did try all possible
>> methods to clinch the part into the metal. No matter how hard even
>> hammering the part in, it does not want to go in. It requires a lot of
>> force to clinch such part into the metal. I need a very powerful tool
>> to do this as the case of the H8 is not aluminum and it is hard steel.
>> Perhaps a HALF TON Power Press will do as this one.

A little benchtop arbor press from harbor freight should do the job.

g.

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[John Evans]

Another option is to find a soft aluminum rivnut that would fit the hole
or a slightly enlarged hole.  They work like pop-rivets to install.

https://www.rivetnutusa.com/rivnut-rivet-nut/

John - Colorado Springs

[norberto.collado koyado.com]

OK, I will give the rivnut a try.

Thanks,

Norberto

---

From: se...@googlegroups.com <se...@googlegroups.com> on behalf of John Evans <john.ev...@gmail.com>
Sent: Thursday, August 5, 2021 6:29 AM

To: se...@googlegroups.com <se...@googlegroups.com>
Subject: Re: [sebhc] H8 Tear down to check the new backplane.

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[norberto.collado koyado.com]

Thanks Paul and Glenn for your feedback. Let me try first the rivenut approach.

Norberto

---

From: se...@googlegroups.com <se...@googlegroups.com> on behalf of Paul Birkel <pbi...@gmail.com>
Sent: Thursday, August 5, 2021 3:22 AM
To: se...@googlegroups.com <se...@googlegroups.com>
Subject: RE: [sebhc] H8 Tear down to check the new backplane.

 

To view this discussion on the web visit https://groups.google.com/d/msgid/sebhc/0a2901d789e3%24cc34c1b0%24649e4510%24%40gmail.com.

[Steven Feinsmith]

Hi Noberto,

You try different methods to fix the problem. My solution is to weld the metal then grind it smooth on both sides. Then drill to make a new hole exact as it was before. Tap to create a thread for a screw into it. I read an article about it a long time ago as I am not a machinist.

Steven

To view this discussion on the web visit https://groups.google.com/d/msgid/sebhc/SN6PR01MB3855F298E8714CC70FC2AC92F7F29%40SN6PR01MB3855.prod.exchangelabs.com.

[norberto.collado koyado.com]

I agree! Worse case, I will bring the chassis to the machine shop. I should get the rivenut this weekend and hope for the best.

Norberto

---

From: se...@googlegroups.com <se...@googlegroups.com> on behalf of Steven Feinsmith <steven.f...@gmail.com>
Sent: Thursday, August 5, 2021 11:28 AM

To view this discussion on the web visit https://groups.google.com/d/msgid/sebhc/CAGJMgmUvEZ67ewxDHjMr5Ae%2BGwcV9MYHNRRp%3D0_E1%2BF3oubu1g%40mail.gmail.com.

[Steven Feinsmith]

Good decision...

Steven

To view this discussion on the web visit https://groups.google.com/d/msgid/sebhc/SN6PR01MB3855D2905B5BB96CE6BA2987F7F29%40SN6PR01MB3855.prod.exchangelabs.com.

[G. Beat]

I thought that Heathkit is ed PEM Fasteners (Penn Engineering), in these instances.

https://www.pemnet.com/fastening-products/pem-self-clinching-fasteners-new/

[Norberto Collado]

My son gave me a preview of the original H8 chassis in CAD today. He shall be done tomorrow. Then he will work on the front panel cover and finally the H8 LED’s cover. He will assembled all the parts in CAD to make sure all holes do align properly. Once he is done, we will make a copy to build out the new H8 chassis using all new components and add the feedback received. At least we will have the original H8 design in CAD.

 

Attached is a picture rear sided view.

 

Thanks,

Norberto

 

 

[Norberto Collado]

H8 Chassis Video attached for fun!

 

Thanks,

Norberto

[norberto.collado koyado.com]

H8 chassis CAD completed. Now what it remains is the top cover and LED protector to have the full system in CAD.

Attached are the pictures for the H8 chassis.

Thanks,

Norberto

[Steven Feinsmith]

That is great your son did a good job!

My question is if we are seeking reproduction of the H8 chassis. Do we need to have an open hole for the transformer? We are no longer using the transformer and large capacitors (linear power supply). We use a switching power supply from Meanwell or PC PSU. We can adjust to a minimum voltage level to run in-board voltage regulators or choose a PC PSU and bypass the voltage regulators. Do we need airflow holes on the bottom and top cover? Should we allow open holes on sides for cooling fans with filters to bring forceful airflow to keep components cool as possible?

In case, we use a linear power supply. It is possible to have a company reproduce the transformer (custom-build). My major concern is electrolytic capacitors nowadays because the ripple current was higher during the old days.

Open to the discussion?

Thank you very much,
Steven

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[Glenn Roberts]

This is a baseline capture of the as-built H8 chassis. It is the logical starting point for any modern manufacturing. As Steven points out before any actual manufacture of new sheet metal it would make sense to do some updates.

Sent from my iPad

On Aug 6, 2021, at 9:47 PM, Steven Feinsmith <steven.f...@gmail.com> wrote:



To view this discussion on the web visit https://groups.google.com/d/msgid/sebhc/CAGJMgmWkfm_8JCHxBRfnRTgDsEnVWhcWF7ZsTRZxZ%2B5HRh5ibA%40mail.gmail.com.

[Norberto Collado]

I see two steps here:

 

1. Reproduction of the original H8 chassis to preserved for history. If someone wants to duplicate the original chassis it can be done.
2. Use the CAD files in step #1 to build the new H8 chassis. There is another email thread in which a lot of feedback was provided on what we need on this new chassis. In this re-design we add the ATX PSU/Mean Well PSU, RS232 holes, etc. I can expand later when we get to step 2.
1. Per feedback from Glenn, the ATX PSU has its own fan and that is enough to cool the chassis. If I see space left in the back to put a small fan, I will do so. The new backplane support the +12V/+5V fans using same 4-pin header as in the PC.

 

 

Thanks,

Norberto

[norberto.collado koyado.com]

Slowly building out the original H8 Chassis. New pictures attached and holes do align nicely.

During my search for the clinch tools, I saw the press inserts that are used on the H8 side panels and ordered a bag.

Thanks,

Norberto

[Norberto Collado]

The rivenut #6-32 worked out fine. Easy to install with the right tools. Not as beautiful as using a clinch nut. To use the clinch nut again, the hole needs to be welded, smoothed, and redrilled as mentioned by Steven. For now the rivenut will do just fine. Tomorrow I will do final inside re-painting to start the build out of the H8 system with the new ATX power supply and new backplane.

 

A note of caution: I only encourage changing the H8 backplane if using the old tin plated pins on the backplane from Heath as it is not reliable. Also if you have a pretty bad H8 system in which the backplane pins were damaged or broken backplane. If your H8 system is using the gold plated pins backplane or using a Trionyx backplane, I do not see the need to change it unless you want to use the dual CPU configuration and protection against shorts. If the H8 original Power supply is working fine, there is no need to change it to a ATX PSU.  This is to preserved the value of the H8 system if you decided to sell it in the near future. I saved all the parts so that I can put it back as the original H8 but using the new backplane. Changing to a ATX PSU is a lot of work and all vintage boards will need to be reconfigured to use 5V inputs. That is a lot of work. Hopefully soon we will have a new chassis that will solve all these upgrade issues.

 

Why I’m doing all these changes to my H8 system? Two reasons: 1. To validate the new H8 backplane with the ATX PSU in a two CPU configuration. 2. To be able to re-create the original H8 chassis in CAD, so that we can develop a new chassis that can support ATX PSU/Mean Well Power Supply along with new chassis enhancements. For this work, I need to strip down the H8 system into bare bones. Also, an opportunity to remove all the rust inside the chassis to protect the metal.

 

 

Tools used:

 

 

[glenn.f...@gmail.com]

The RivNut’s a great solution.  Thanks to John Evans for mentioning this!

 

I have an H8 chassis that had previously been used as an expansion box on an old H8.  There was a home-brew ribbon cable arrangement to string two busses together and (unfortunately) slots cut into the side panels to pass the ribbon cable through.  The chassis had a linear power supply but not all the original Heath parts.  And no front panel…  the backplane used the old tinned connectors…

 

So this is an ideal chassis to build out my “H8-2020” with the Rev 4 CPU and new front panel and backplane boards.  Initially I am patching the side panels (will post pictures separately) but I intend eventually to fabricate some nice looking wooden ones (thanks Norberto for posting a source for the brass screw fittings for the side panels!

 

 

 

From: se...@googlegroups.com <se...@googlegroups.com> On Behalf Of Norberto Collado
Sent: Sunday, August 08, 2021 12:29 AM
To: se...@googlegroups.com
Subject: Re: [sebhc] H8 Tear down to check the new backplane.

 

The rivenut #6-32 worked out fine. Easy to install with the right tools. Not as beautiful as using a clinch nut. To use the clinch nut again, the hole needs to be welded, smoothed, and redrilled as mentioned by Steven. For now the rivenut will do just fine. Tomorrow I will do final inside re-painting to start the build out of the H8 system with the new ATX power supply and new backplane.

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[Norberto Collado]

Glenn,

 

Once we are done with the CAD model, I will send you the information on the side panels. I will check if we can do a 3D print to test it out. Making wooden ones will be great and paint them the same color as the PDP-8 replica. At work I used to have a PDP-8 and the enclosure was all shiny wood and it was very beautiful.

 

 

Also, on my H8, I intend to expand outside the H8 into another H8 backplane, but using 2x DB25 cables into the second chassis.

 

On the brass screw fittings for the side panels, I will send you some as I will get 50-pcs. 😊

https://www.amazon.com/240-006-BR-Flush-Press-Insert-Brass/dp/B06XGK7XQR/ref=sr_1_2?dchild=1&keywords=flush+insert+brass+240-006-br&qid=1628446839&sr=8-2

 

For the RivNut, I bought everything in Amazon. Also in Amazon I bought the following parts to replace the old ones and they fit nicely into the H8 chassis. I think we can buy all the parts in Amazon for the H8 chassis…

 

 

https://www.amazon.com/dp/B0839KVBKB?psc=1&ref=ppx_yo2_dt_b_product_details

 

 

 

 

https://www.amazon.com/dp/B071ZM852H?psc=1&ref=ppx_yo2_dt_b_product_details

 

 

 

https://www.amazon.com/gp/product/B07MSHD726/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1

 

 

 

Thanks,

Norberto

 

 

From: "se...@googlegroups.com" <se...@googlegroups.com> on behalf of <glenn.f...@gmail.com>

Reply-To: "se...@googlegroups.com" <se...@googlegroups.com>
Date: Sunday, August 8, 2021 at 4:40 AM
To: "se...@googlegroups.com" <se...@googlegroups.com>

Subject: RE: [sebhc] H8 Tear down to check the new backplane.

[Glenn Roberts]

I will probably use a blank from Woodcraft:

 

https://www.woodcraft.com/categories/wood?thickness%5B%5D=3%2F4%22&width%5B%5D=6%22

 

thoughts suggestions welcome; also on stain and finish…  possibly walnut or cherry…  wondering of there was a particular wood or finish that was popular back in the 70s (e.g. for home stereos, etc.)?

 

 

 

From: se...@googlegroups.com <se...@googlegroups.com> On Behalf Of Norberto Collado

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[norberto.collado koyado.com]

Almost done with the H8 original chassis in CAD. Top cover and cross bar are what is left. Attached is latest chassis picture. So far, all holes align properly.

Les, Glenn,

I'm trying to figure out on how to attach the ATX power supply to the chassis to put it back. Any ideas on how you did it?

Thanks,

Norberto

---

From: se...@googlegroups.com <se...@googlegroups.com> on behalf of Glenn Roberts <glenn.f...@gmail.com>
Sent: Monday, August 9, 2021 8:03 AM

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[Les Bird]

Norby,

Mine is not mounted in but instead it just fits snuggly at the back of the chassis wedged between the back panel and the raised mounts for the transformer. See photo:

[norberto.collado koyado.com]

Thanks for the feedback!

Norby

---

From: se...@googlegroups.com <se...@googlegroups.com> on behalf of Les Bird <les...@bellsouth.net>
Sent: Wednesday, August 11, 2021 9:47 AM
To: SEBHC <se...@googlegroups.com>

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[Steven Feinsmith]

The chassis showed covers for a high-voltage circuit on the left side and capacitors on the right side. They will no longer when we use ATX (PSU). I planned to use Dell's PS-5161-1D1 that provide 160 watts as follows:

+3.3v @ 9A MAX
+5V @ 11A MAX
+12V @ 9A MAX
-12V @ 0.5A MAX
+5VFP @ 2A MAX
+5V and +3.3V load sharing will not be greater than 85W Max. continuous load DC output power shall not exceed 160W.

I believe this device is enough to power the H8 system. The only problem with this unit is that it needs to mount on the left side because of the exhaust vent and AC power socket. The internal fan should be enough to pull airflow from the rest of the chassis. If you seek ATX devices (box style) on many PCs may not have enough room to fit the chassis unless to increase the rear end area.

Here are two pictures to give you an idea:

This power supply is a compact style used on Dell computers, and it is not expensive. I got it from eBay a long time ago.

Thank you,
Steven

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[glenn.f...@gmail.com]

I used an Athena Power model AP-MTFX30 in Rusty (which conforms to the “TFX” form factor specification):

 

AP-MTFX30 | athenapower.com

 

https://photos.app.goo.gl/h1949iRCWefnuS7z6

 

it makes for a clean looking install because the fan grille lines up very nicely in the space where the transformer had been:

 

https://photos.app.goo.gl/LegyK8miY4oZLhP86

 

(however I did have to drill new holes).

 

the only problem is that the screws that hold the power supply to the case are those stubby coarse-threaded screws used in PC fans, and they’re screwed into plastic.  If I ever shipped the unit I’d want to remove the power supply as I don’t trust those screws to hold it.

 

as you can see I never got around to adding a cord restraint for the power cord.  I connected the switch to the appropriate power-on connections on the power supply (sorry can’t recall which lines those are but happy to report back more if needed).

 

On my “H8-2000” boards there were originally jumpers across input and output on all of the 5V regulators, but I’ve slowly added Pololu regulators to most of my boards so I can swap at will between PC-style and H8 analog powered chassis.

To view this discussion on the web visit https://groups.google.com/d/msgid/sebhc/SN6PR01MB38559616B4456BB747724B2EF7F89%40SN6PR01MB3855.prod.exchangelabs.com.

[norberto.collado koyado.com]

Thanks for the feedback!  I will work on this as I need my system up and running again with a secured PC power supply.

Norby

---

From: se...@googlegroups.com <se...@googlegroups.com> on behalf of glenn.f...@gmail.com <glenn.f...@gmail.com>
Sent: Wednesday, August 11, 2021 11:25 AM

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[G. Beat]

Desktop Platform Form Factors Power Supply

Intel Corporation 

Design Guide, June 2018, Revision 002 (67 pages)

https://www.intel.com/content/dam/www/public/us/en/documents/guides/power-supply-design-guide-june.pdf

[G. Beat]

The other option is to Specify a Popular SMPS, like MeanWell.

https://www.meanwell.com/meanwell_products.html#tag-6-16

Using either an Enclosed or Open Frame model. Preference to enclosed models (safety in open computer case).

greg

elmhurst, il

On Wednesday, August 11, 2021 at 2:19:28 PM UTC-5 Norby wrote:

[Norberto Collado]

Latest pictures and we shall be done by this weekend in duplicating the original H8 chassis in CAD.

 

I did not realize until now that the H8 chassis is beautifully designed. Not like the PC that is a rectangular enclosure with no beauty in mind. I’m impressed that such small chassis could be that powerful.

 

Thanks,

Norberto

 

 

 

 

 

 

[Glenn Roberts]

Beautiful work. Your son is a magician with that CAD tool!

Sent from my iPad

On Aug 12, 2021, at 10:46 PM, Norberto Collado <norberto...@koyado.com> wrote:



Latest pictures and we shall be done by this weekend in duplicating the original H8 chassis in CAD.

 

I did not realize until now that the H8 chassis is beautifully designed. Not like the PC that is a rectangular enclosure with no beauty in mind. I’m impressed that such small chassis could be that powerful.

 

Thanks,

Norberto

 

<image001.png>

 

<image002.png>

 

<image003.png>

 

<image004.png>

 

<image005.png>

 

<image006.png>

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[Terry Smedley]

I agree!  The CAD work is beautiful!  Thanks to all the Collados.

I imagine the original engineering drawings were put on vellum with a T-square and Koh-i-Noor (and assorted "felt case" instruments).  

Terry

[Norberto Collado]

Hello,

 

I completed testing with the ATX Power Supply on the H8 with the new backplane. It was hard to figure out on how to attached the ATX Power Supply into the H8 chassis.

 

As I want to still support the 7805 regulators I decided to use two small power supplies. One for +15v/-15V around 1A, and a 8V power supply at 10A.

 

Here are some pictures with the two Power Supplies attached. I shall be able to start tomorrow in putting the system back. I just needed to drill two small holes as the second hole was already there. So both Power Supplies are secured.

 

I will use the fuse hole to attached a switch to provide reset to the second CPU board. More pictures to come.

 

Thanks,

Norberto

 

[Norberto Collado]

I have an H8 chassis that had previously been used as an expansion box on an old H8.  There was a home-brew ribbon cable arrangement to string two busses together and (unfortunately) slots cut into the side panels to pass the ribbon cable through. 

 

Glenn,

 

I asked my son to 3D print the side panels to verify alignment with the actual H8 chassis.  Once I’m done, I will send you the two side panels. I already received the brass screws and will be installing them on the side panels.

 

Thanks,

Norberto

[Glenn Roberts]

I’ll certainly be anxious to see how the 3-D printing comes out!  I can show this off at VCF East.

 

In fairness I should mention that I have repaired the holes in the side panels with a fairly good outcome.  I’ll post pix and more info soon…

 

I’m still planning to make some wooden side panels as well, so I’ll have to get some of those brass inserts for that…

 

Thanks!

 

• Glenn

 

 

From: se...@googlegroups.com <se...@googlegroups.com> On Behalf Of Norberto Collado
Sent: Saturday, August 14, 2021 3:41 PM
To: se...@googlegroups.com
Subject: Re: [sebhc] H8 Tear down to check the new backplane.

 

I have an H8 chassis that had previously been used as an expansion box on an old H8.  There was a home-brew ribbon cable arrangement to string two busses together and (unfortunately) slots cut into the side panels to pass the ribbon cable through. 

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[Steven Feinsmith]

Both sides can be created with wood or plastic through a milling machine. I know many people do not have that heavy machine. The alternative is to use your skill with a router, press drill, radial saw, and few others that can make excellent pieces of side replacement for the H-8.

The problem is metal sheets to create the top cover, bottom/rear end sheet, front panel, and some metal to support the cards. I am aware the cost of fabricating the metal is pretty expensive and must have a large volume. I do not know anyone who is tremendous still in metalworking to create parts. The situation is an enormous challenge at this time. I assume if we can find metalworking from China, it may be much cheaper to produce as many as 100 pieces. Any ideas?

Steven

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[Paul Birkel]

Consider creating an alternative top-panel using an array of perforations rather than louvers, which may then be less expensive to manufacture.  Different look, of course …

To view this discussion on the web visit https://groups.google.com/d/msgid/sebhc/CAGJMgmUCAxa5T9BKibpmrKbuQuBgxjz7c2gt_oJwcdF6kermvg%40mail.gmail.com.

[Steven Feinsmith]

For the suggestion, using an array of perforations will look ugly appearance.

Thank you,

Steven

To view this discussion on the web visit https://groups.google.com/d/msgid/sebhc/034d01d791a1%24f2aa2cc0%24d7fe8640%24%40gmail.com.

[Norberto Collado]

Hello Glenn,

 

Sure, I will send you the brass inserts.

 

My son printed the right side panel. As his 3D printer is small, he printed it into 2 parts just to check alignment. He had to do some minor adjustments after installing it into the H8 chassis. Ink well spend. We will need to find a 3D print manufacturer  that can handle bigger sizes.

 

Here is a picture of the 3D prototype.

 

Norberto

[Norberto Collado]

I do not think we need to add holes to the top of the enclosure. A small +12V fan attached to the side panel should do just fine. Or if using a PC power supply, the fan is built in.

 

Norberto

 

For the suggestion, using an array of perforations will look ugly appearance.

 

Thank you,

Steven

 

 

On Sun, Aug 15, 2021 at 2:51 AM Paul Birkel <pbi...@gmail.com> wrote:

Consider creating an alternative top-panel using an array of perforations rather than louvers, which may then be less expensive to manufacture.  Different look, of course …

 

From: se...@googlegroups.com [mailto:se...@googlegroups.com] On Behalf Of Steven Feinsmith
Sent: Saturday, August 14, 2021 7:18 PM
To: se...@googlegroups.com
Subject: Re: [sebhc] H8 Tear down to check the new backplane.

 

Both sides can be created with wood or plastic through a milling machine. I know many people do not have that heavy machine. The alternative is to use your skill with a router, press drill, radial saw, and few others that can make excellent pieces of side replacement for the H-8.

The problem is metal sheets to create the top cover, bottom/rear end sheet, front panel, and some metal to support the cards. I am aware the cost of fabricating the metal is pretty expensive and must have a large volume. I do not know anyone who is tremendous still in metalworking to create parts. The situation is an enormous challenge at this time. I assume if we can find metalworking from China, it may be much cheaper to produce as many as 100 pieces. Any ideas?

Steven

.

[glenn.f...@gmail.com]

Very nice!  So for this prototype are the two printed sections attached to each other somehow?  How?  Obviously for any serious production we’d need a single piece. 

 

From: se...@googlegroups.com <se...@googlegroups.com> On Behalf Of Norberto Collado
Sent: Monday, August 16, 2021 1:08 AM
To: se...@googlegroups.com
Subject: Re: [sebhc] H8 Tear down to check the new backplane.

 

Hello Glenn,

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[norberto.collado koyado.com]

So, for this prototype are the two printed sections attached to each other somehow?  How?

With Epoxy or Super Gorilla glue to play with it is fine, but not for production.

Norby

---

From: se...@googlegroups.com <se...@googlegroups.com> on behalf of glenn.f...@gmail.com <glenn.f...@gmail.com>
Sent: Monday, August 16, 2021 5:06 AM
To: se...@googlegroups.com <se...@googlegroups.com>
Subject: RE: [sebhc] H8 Tear down to check the new backplane.

 

[norberto.collado koyado.com]

I started to build out my H8 system last night as shown in the attached picture. I have a quick question for the experts on power cables. For the 8V power supply, I'm using 18AWG cable, but my heart is telling me to 16AWG as the target is to support 10AMPS max.  Any feedback appreciated, so that I can use proper power cable AWG.

I left the power transformer cut out open as my son is creating me a 3D print cover to support the Parallel printer connector, a single USB connector , dual DB9's, and a reset switch for the second CPU. Terry Gulczynski provided great feedback on what he did for his H8 system and how to utilize best any opening in the H8 system with different cover plates for different configuration needs. So, I decided to use such opening for same purposed.

Also, I updated with new parts the power cable, on/off switch, fuse holder, and the 120VAC power outlet for the H19 terminal. I cannot complete the build-out as I'm still waiting for the new fuse holder. All parts available in Amazon.

Thanks,

Norberto

[Glenn Roberts]

I am no such expert but this chart is saying 16:

 

https://www.bluesea.com/resources/1437

 

I found a few others with similar info.

 

From: se...@googlegroups.com <se...@googlegroups.com> On Behalf Of norberto.collado koyado.com
Sent: Saturday, August 21, 2021 5:44 PM
To: se...@googlegroups.com

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[Norberto Collado]

Thanks Glenn!

 

I found a white wire 16 AWG in my tool box and replaced both 18 AWG cables with this one. I colored the end in red, so that I know which one is ground and which one is positive.

 

Norberto

 

From: "se...@googlegroups.com" <se...@googlegroups.com> on behalf of Glenn Roberts <glenn.f...@gmail.com>

Reply-To: "se...@googlegroups.com" <se...@googlegroups.com>
Date: Saturday, August 21, 2021 at 5:48 PM
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[Lee Hart]

Wire tables are based on (often unstated) assumptions about the insulation, allowable temperature rise, and acceptable voltage drop. The wire itself can carry substantially more than what you see in wire tables.

For your H8, voltage drop is probably the most important parameter. Here's how I would size it: Let's say you will accept a 2% voltage drop in the 5v supply; That's 5v x 0.02 = 0.1v. Half of that will be in the +5v lead, half in the GND lead. Further, let's say the total wire length is 2 feet (12" for the +5v wire, 12" for the GND wire).

Now, let's assume your maximum current is 10 amps. A 0.1v drop at 10 amps is R=V/I = 0.01 ohms. Looking at a wire table,

#16 is 0.00401 ohms per foot, so 2 feet would be 0.008 ohms.

#18 is 0.00639 ohms per foot, so 2 feet is 0.0128 ohms.

Either is close enough to work. I doubt you'll see anything close to 10 amps. :-)

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[norberto.collado koyado.com]

Thanks, Lee, for such information and how to do the correct math base on voltage drop.  AG #16 gives less voltage drop. I was checking the cable that HealthKit used, and it is #16 AWG.

With the new boards I do not think we can get to 10A, but I tested the board with resistors to make sure it can handle properly 10A. I did not want the backplane voltage traces to become a fused when reaching such currents if ever.

Thanks,

Norberto

---

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Sent: Monday, August 23, 2021 12:39 PM
To: se...@googlegroups.com <se...@googlegroups.com>

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[norberto.collado koyado.com]

Attached is the H8 transformer 3D print cover plate to support USB, serial ports, parallel printer port, and reset switch. I just need to sand it, give it a bath with epoxy to hardener, and some black paint.

---

From: se...@googlegroups.com <se...@googlegroups.com> on behalf of norberto.collado koyado.com <norberto...@koyado.com>
Sent: Monday, August 23, 2021 9:25 PM

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[Steven Feinsmith]

It Looks great!!!

Steven

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[norberto...@koyado.com]

Received today remainder parts to put back together the H8 system. Now I have all new parts for the AC input into the chassis. I hope to finalized by Friday.

 

Thanks,

 

Norberto

 

 

 

[Norberto Collado]

Powered-up the updated H8 system and it came up nicely. Now I have less weight on the chassis and I can use last slot on the H8 backplane with space still left.  Below is a two CPU configuration to do a quick verification that the main CPU was still operational.

 

One power supply provides +8Volts and the second power supply provides +5V,+15V, and -15V to support legacy Heath boards.

 

Here are some pictures.

 

 

 

 

Thanks,

Norberto

[norberto...@koyado.com]

Adding mini speaker to H8 Front Panel!

 

[Glenn Roberts]

Congratulations. It’s been a long road. Looks like you added a stiffening bar to the front panel? We talked about a number of approaches. What did you end up using?

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On Sep 2, 2021, at 2:42 AM, norberto...@koyado.com wrote:



Adding mini speaker to H8 Front Panel!

 

<image003.jpg>

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[glenn.f...@gmail.com]

Did you just hot glue that to attach it?

 

From: se...@googlegroups.com <se...@googlegroups.com> On Behalf Of norberto...@koyado.com
Sent: Thursday, September 02, 2021 2:43 AM
To: se...@googlegroups.com
Subject: RE: [sebhc] H8 Tear down to check the new backplane.

 

Adding mini speaker to H8 Front Panel!

 

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[Norberto Collado]

 

I added a little hot glue on one side, but the soldered wires can do the job. The sound of such speaker is soft and not as loud as the original. For me that works better as it doesn’t bother my ears when beeping. Also my wife approved it as the original sound was loud and bother her as well.

 

On the stiffening bar, it is not needed for the production boards. The FP pictured here is my first prototype which is thinner than the production board and requires such bar. Also this proto board is missing a lot of features.

 

Thanks,

Norberto

 

From: "se...@googlegroups.com" <se...@googlegroups.com> on behalf of <glenn.f...@gmail.com>
Reply-To: "se...@googlegroups.com" <se...@googlegroups.com>
Date: Thursday, September 2, 2021 at 9:26 AM
To: "se...@googlegroups.com" <se...@googlegroups.com>
Subject: RE: [sebhc] H8 Tear down to check the new backplane.

 

Did you just hot glue that to attach it?

 

From: se...@googlegroups.com <se...@googlegroups.com> On Behalf Of norberto...@koyado.com
Sent: Thursday, September 02, 2021 2:43 AM
To: se...@googlegroups.com
Subject: RE: [sebhc] H8 Tear down to check the new backplane.

 

Adding mini speaker to H8 Front Panel!

 

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[Lee Hart]

PS: Watch out for undersized wire. Like so many things today, some of the no-brand wire you'll find on the market is under-sized! Copper is expensive, so vendors are tempted to "cheat" on the size. This problem seems especially common in automotive wire.

You can check the size with a wire-stripper (when it doesn't fully cut the insulation), or with a micrometer (if you have one handy), or a micro-ohmmeter (which basically measures thevoltage drop at a known current).

Lee Hart

To view this discussion on the web visit https://groups.google.com/d/msgid/sebhc/2995B434-2E77-49A4-B943-438BA52D702F%40koyado.com.

[norberto...@koyado.com]

Thanks for the feedback. I will check voltage drop as I add boards to find out if gauge is correct.

 

Norby

 

From: se...@googlegroups.com <se...@googlegroups.com> On Behalf Of Lee Hart
Sent: Thursday, September 2, 2021 9:21 PM
To: se...@googlegroups.com

To view this discussion on the web visit https://groups.google.com/d/msgid/sebhc/CAF__8heX-NQM5AMYF-aY881sTHakk9yxXhC7g06hAsPi07dGJA%40mail.gmail.com.

[Glenn Roberts]

Also watch out for copper clad aluminum fakes

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On Sep 3, 2021, at 3:05 AM, norberto...@koyado.com wrote:



<image001.jpg>

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[norberto.collado koyado.com]

As I put together the updated H8 system, Heath used a 15-pin ribbon cable for the H19 RS-232 connection. Actually, the H8/H89 RS232 interface only supports 8 signals, so no need to have 15 cables total for H19 RS-232. So, I'm building a new cable that goes from the H8 15-pin header to DB9 female connector and from here to a DB25 H19 connector. Having a DB9 female connector allows to go to USB or networked serial adapters. More flexibility with DB9. 

Once done, I will post the wiring diagram.

Thanks,

Norberto 

[Norberto Collado]

Today added the I/O cover plate to H8 system, so that cable management is more cleaner.

 

Here are some pictures:

 

 

 

 

 

[Glenn Roberts]

Very nice!

Are you still using the thumb switches on the Z67-IDE+? I don’t see those…

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On Sep 18, 2021, at 8:42 PM, Norberto Collado <norberto...@koyado.com> wrote:



Today added the I/O cover plate to H8 system, so that cable management is more cleaner.

 

Here are some pictures:

 

<image001.jpg>

 

<image002.jpg>

 

<image003.jpg>

 

 

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[Norberto Collado]

Yes! They are on the external enclosure with  the Z67-IDE+. I just bring the SASI cable out to it. Also looking into using the solution provided by Terry S. which uses the Rotary Encoder Module to manage the LCD Menu.

 

 

 

Terry S. solution to eliminate the BCD switches:

 

Thanks,

Norberto

 

From: "se...@googlegroups.com" <se...@googlegroups.com> on behalf of Glenn Roberts <glenn.f...@gmail.com>
Reply-To: "se...@googlegroups.com" <se...@googlegroups.com>
Date: Saturday, September 18, 2021 at 7:37 PM
To: "se...@googlegroups.com" <se...@googlegroups.com>
Subject: Re: [sebhc] H8 Tear down to check the new backplane.

 

Very nice!

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