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Old 13th September 2011, 06:42 PM   #691
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Another single source part is out of stock at Mouser. It's one of the two battery clips. The Keystone 593/594 are close to being the same as the Eagle parts specified but have a slightly different footprint. When I first designed the board Mouser didn't have one of the Keystone parts in stock but they have lots of them now. The Keystone parts are also about twice the price.

There's a regular wire leaded battery clip listed as an alternate on the BOM. Those will certainly work if you can find another way to secure the batteries. They could also be used temporarily until the Eagle parts are back in stock.

The battery clips are tricky in terms of where the batteries end up relative to the back of the case. The drawings don't answer the question of how far the battery snaps onto the clip. I'm reluctant to change the footprint at the last minute to the Keystone part when 600+ boards are about to be ordered and have it not work for some reason.

In hindsight, I wish I'd gone with the Keystone part in the first place. But this could have just as easily happened the other way around. Single source parts are always a potential problem. It's unfortunate companies like Eagle and Keystone don't just use the same footprint.

I'm looking into modifying the current Eagle footprint with bigger holes slightly shifted to perhaps barely accommodate both the Eagle and Keystone parts. The downside will be neither will be as good of fit and it will likely be difficult to align the clips if you don't use a dead battery clipped in place while soldering them. And I can't really know where the ends of the batteries will hit with respect to the back edge of the PCB when using the Keystone clips. It should be similar to the Eagle clips but it's hard to know for sure.
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Old 13th September 2011, 07:02 PM   #692
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IMHO unless the difference in fit is really tiny that would be a compromise too far.
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Old 13th September 2011, 08:51 PM   #693
timpert is offline timpert  Netherlands
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Wouldn't something like the Keystone 1294 or 1291-79 or 303-P fit on the board without modifications? You could glue these to the board with some adhesive to give the battery mounting additional strength.
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Old 13th September 2011, 09:13 PM   #694
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@Timpert, that's a good question as they have plenty of those in stock. The reason I didn't use the full holders (besides the higher price) was to save space. I needed every square millimeter I could get so the batteries are shoved together and as far left as they can go (both of which also helps secure them and keep them in place).

The batteries are only about 26mm wide. The plastic holders are 29.6mm and the metal ones are 28.6mm wide. That's about 370 square mm of extra board space which might not seem like much, but it's about 5% of the total usable board area and I didn't have it to spare without compromising the design in other ways.

Hopefully I can get the Keystone 593/594 to also fit. It might even be possible to trim/bend the 593/594 to fit as-is.
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Old 14th September 2011, 12:00 AM   #695
orpheus is offline orpheus  United States
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Just paid for 3 more boards, so have a total order of 6.

Thank you for your work on this group buy!

Aaron.
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Old 14th September 2011, 12:38 AM   #696
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I would like to have 4 more boards , EU
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Old 14th September 2011, 05:45 AM   #697
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The latest prototype board works GREAT! In every test I've run so far it matches or outperforms the last PCB revision. Everything fits and both shaft lengths of the Alps and Bourns pots work exactly as I hoped. I may try to move the gain resistors slightly to make it easier to use the SIP pin sockets for solderless resistor changes. And I also am still working on the hopefully allowing the Keystone battery terminals as an alternative to get around the Mouser out of stock problem.
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Old 14th September 2011, 11:33 AM   #698
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Quote:
Originally Posted by RocketScientist View Post
The latest prototype board works GREAT! In every test I've run so far it matches or outperforms the last PCB revision. Everything fits and both shaft lengths of the Alps and Bourns pots work exactly as I hoped. I may try to move the gain resistors slightly to make it easier to use the SIP pin sockets for solderless resistor changes. And I also am still working on the hopefully allowing the Keystone battery terminals as an alternative to get around the Mouser out of stock problem.
Does this mean it is ok for me to close the GB and get the order placed, or do you want me to wait while you shuffle the gain resistors around etc?

I've also updated the quatities for those that have requested more boards. Check to see how much more you need to throw in. If you want to check it with me then just send me a PM or an e-mail.

Last edited by olli1324; 14th September 2011 at 11:46 AM.
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Old 14th September 2011, 11:55 AM   #699
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If it is not to late I would like to have:

2 boards, EU-area (Sweden).
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Old 14th September 2011, 11:59 AM   #700
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