Just realized I should have thanked Birgir as well for all of his efforts on the KGST project

I don't mind.   

22 hours ago, Kerry said:

I wanted to redo this as a single 4 layer board.  The board is 111mm x 150mm.  I'm pretty happy.  Should have it back pretty soon and will give it a go.

It supports a couple of styles of the servo for the offset so I can play a bit.

 

It's fantastic! Thanks for your sharing.

The pot. pin definition will be only for alpha? or Alps?

It's just the alpha.  I suppose I could figure out if both could fit.  I think the goldpoint or DACT could be made to work too.

15 hours ago, Kerry said:

On my first version I did the heater wiring off board.  I wanted to get it on the board this time.  I used the 4 layers so that there would be a solid ground plane under the heaters and between any signal / voltage traces.  I also made sure there was some ground plane on top between the heater and servo which at worst would introduce common mode noise.

Looks very interesting. Would it be possible to have some pictures of the inner layers? What might the maximum voltage between layers be?

Beautiful symmetry of the board.

Kerry, have you compared the Supertex and Microchip versions of the DN2540?

like i have time for that at this point.

No I haven't. Have you and do you see or header a difference?

I just bought a bunch of the Microchip SMD version.

No I haven't. Have you and do you see or header a difference?

I just bought a bunch of the Microchip SMD version.

Yeah, good news is that they are cheaper

I was looking at Octopart last night and noticed that their descriptions of the parts hinted that they are different. I haven't dug into the datasets yet.

On 2015/12/8 at 0:58 PM, Kerry said:

It's just the alpha.  I suppose I could figure out if both could fit.  I think the goldpoint or DACT could be made to work too.

Thanks, Kerry.

Where can source Alpha's pot? direct from factory?

Looks like the Microchip version is just a Supertex device with their own branding

The only difference I could find is the document version.

Supertex = Version E051509

Microchip = Version F111010

From Octopart, the datasheet link for the Supertex device sends you here:-

http://datasheet.octopart.com/DN2540N8-G-Supertex-datasheet-14062240.pdf

From Octopart, the datasheet link for the Microchip device sends you here:-

http://datasheet.octopart.com/DN2540N8-G-Microchip-datasheet-27836262.pdf

From the Microchip site the datasheet is:-

http://ww1.microchip.com/downloads/en/DeviceDoc/DN2540%20B060313.pdf

which is exactly the same document as the one just above.

Both are Supertex Doc. #:DSPD-3TO243AAN8, Version F111010

6 hours ago, palchiu said:

Thanks, Kerry.

Where can source Alpha's pot? direct from factory?

The factory have a 1000pc min order.

I don't know anywhere else you could get these, I've been looking around EVERYWHERE and have come up with nothing.

 

I think just Justin and I have sold them in the past but I'm running low and Justin might be as well.  I will restock at some point but I won't sell them as I will probably stop selling parts soon.   

Beautiful work as always Kerry. 

Wondering if boards or gerber files will be available to the general public? 

I'm going to test the current boards first. I don't mind making them available to people.

On 2015/12/10 at 3:23 PM, johnwmclean said:

The factory have a 1000pc min order.

I don't know anywhere else you could get these, I've been looking around EVERYWHERE and have come up with nothing.

 

too bad, not found any seller.  

Group buy for 4 gang Alpha pot?

That would be a rather gigantic investment for a groupbuy.... 

We have to think big sometimes....   Imagine if every builder buys 5 units, then we need 200 members. Do we have 200 active diy builders in our group?????

Go ahead, think big.    It is certainly one of the best pots ever made. 

What sort of price is the Alpha at 1k quantities?

 

//UFN

Around the 10$ mark F.O.B.  I'm sure the TKD's are around this level as well in these quantities. 

I’d take $500 worth for 50 pc’s no problem.

I can probably do 25 or so pieces.

17 hours ago, spritzer said:

Around the 10$ mark F.O.B.  I'm sure the TKD's are around this level as well in these quantities. 

Thanks. Even if the final price ends up being in $18-$20 range I'm pretty sure they'd go fairly quickly.

Of course doing this is either a ton of legwork to run a GB or quite a bit of risk for someone to front the cash, buy the lot and then sell them off afterwards. Not sure if we have volunteers for either?

 

//UFN