Folsom's great little 7297 Chip Amp

lacro · « **Reply #600 on:** 20 Sep 2016, 09:08 pm »

Quote from: Folsom on 20 Sep 2016, 06:43 pm

I'm down to 6 amp boards, and around 20 Antipoles. One gentleman has a claim to 5 amp boards if he claims them soon, but otherwise, I guess... form a line

If I reprint I don't know when at this point, because they won't pay for themselves anytime too soon.

“I silently smiled at my incessant good fortune.”
― Henry David Thoreau

Folsom · « **Reply #601 on:** 21 Sep 2016, 05:43 pm »

Amplifier boards are gone. I have around 15 Antipoles left.

BRN · « **Reply #602 on:** 21 Sep 2016, 07:02 pm »

Man I can't believe I missed the post. I would have purchase another board or two.

Folsom · « **Reply #603 on:** 21 Sep 2016, 08:21 pm »

If I had a sufficient order load I would have more printed.

Maybe if there's enough interest then it will happen. I believe it would require around 20-25 orders. The new boards would be updated slightly, nothing performance wise just slightly cleaner appearance skipping a few things no one uses.

KR500 · « **Reply #604 on:** 22 Sep 2016, 06:09 pm »

I really didn't want to bend the chip or de/re solder to match the chip up against the heat sink
So, using a little "strategery" I used the next smaller standoff post on the rear of the amp board and took some pictures to see if you guys think this is acceptable ? The mica is not on it yet .
toothed lock washers on the PCB and heat sink bolts so they don't wander around.
Also some pictures of the bottom top and rear vent holes . If tyhey aren't enough I'll add more
thanks

lacro · « **Reply #605 on:** 22 Sep 2016, 07:04 pm »

Quote from: KR500 on 22 Sep 2016, 06:09 pm

I really didn't want to bend the chip or de/re solder to match the chip up against the heat sink.

It will probably be fine, You may be overthinking this. I would have tried bending the chip back in alignment. Your not really bending the chip just the leads. One piece of advise I can give after soldering a few of these amp boards is leave the big transistor for last. Trying to keep it from bending while your soldering on the all the wires is difficult. Also, I found that installing the small heat sink on it before soldering to the board was easier. Just my thoughts, your mileage may vary....

lacro · « **Reply #606 on:** 22 Sep 2016, 07:17 pm »

Hey - I just noticed something else with your board. there has been a BOM change from the 10 uF blue cap to this:
http://www.mouser.com/ProductDetail/Cornell-Dubilier/107CKS016M/?qs=%2fha2pyFaduj0NJWQ67zoZIQXKYIad%252bbmZSt3Q9Xez%2fAo6kG9mWogPA%3d%3d

Folsom · « **Reply #607 on:** 22 Sep 2016, 08:13 pm »

The mica will push it out a little bit. You should be fine. You can put it in, and check thermal grease for contact when you take it out.

The bigger cap just prevents the turn on pop, which is harmless to all but the most insanely fragile speakers. I'm not sure such a speaker exist, to be honest, at least that anyone uses an amp with... Headphones maybe?

BRN · « **Reply #608 on:** 23 Sep 2016, 05:08 pm »

Quote from: Folsom on 21 Sep 2016, 08:21 pm

If I had a sufficient order load I would have more printed.

Maybe if there's enough interest then it will happen. I believe it would require around 20-25 orders. The new boards would be updated slightly, nothing performance wise just slightly cleaner appearance skipping a few things no one uses.

You can put me down for 3 boards.

KR500 · « **Reply #609 on:** 23 Sep 2016, 05:11 pm »

Thanks for your post and suggestion about leaving the transistor til last.
I think I did order one of those parts for the turn off pop reduction.
I appreciate your help as I'm still a newb moving forward.

Folsom · « **Reply #610 on:** 23 Sep 2016, 07:04 pm »

Hi guys, I got 2 available amp boards from the claimed 4. They go to whomever also wants Antipoles, first.

shadowlight · « **Reply #611 on:** 23 Sep 2016, 07:28 pm »

Folks, who are using the NABU case how did you get the IEC outlet cut into it?

Odal3 · « **Reply #612 on:** 23 Sep 2016, 07:41 pm »

Congratulations on selling out! Hope you'll sell many more!

limits · « **Reply #613 on:** 23 Sep 2016, 07:43 pm »

Sorry, shadowlight--I'm no help. I ended up using the captive power cord that came with the case. I am sure they make chassis punches for this, but if you're only doing one (or even a few) it might not be worth the cost.

Maybe a drill press drilling small holes for the profile, and finishing it off with sidecutters?...

Good luck with yours!

limits

KR500 · « **Reply #614 on:** 23 Sep 2016, 08:06 pm »

I used a sabre saw with metal blade where I removed the original NABU heat sink from the chassis rear plate for the Furutech power inlet cut out, use a safety face face shield to stop getting metal shrapnel and file the edges of the cut out smooth. The dimensions in MM are on the Furutech site for the cutout size of the inlet. I started from one of the original heat sink mounting holes and drilled each corner I marked out with some drill bits starting small till I got to a size that would allow a saw blade in. Use a slow speed on the drill and lubricating oil.
Jeremy , I will take an amp board unless an Antipole buyer needs it

thanks

Folsom · « **Reply #615 on:** 23 Sep 2016, 08:11 pm »

Sales pending.

Folsom · « **Reply #616 on:** 23 Sep 2016, 11:39 pm »

Ok.

1x DIY7297 board left to go with an Antipole to whomever wants the set.

Sold sold.

indosmokejon · « **Reply #617 on:** 26 Sep 2016, 07:37 pm »

Can anyone weigh in on which power transformer will work best with the antipole and the amp in general, the Hammond in the BOM or the Anitech that Matt Garman used, http://www.antekinc.com/as-1218-100va-18v-transformer/ I am going to build two units and I can get two of the anitek's to the door for roughly $55, so a little cheaper than going with the Hammond units. I know that Folsom also mentioned the James Transformer as well which would be a bit more expensive than either of the previously mentioned transformers. The anitech's would allow me more options with enclosures since they don't sit as high. Thoughts???

Odal3 · « **Reply #618 on:** 26 Sep 2016, 08:05 pm »

Speaking of the James O core transformers - anyone tried one?

Folsom · « **Reply #619 on:** 26 Sep 2016, 08:18 pm »

I've tried to order from James and been met with 0 success. Crying shame, I think they'd be excellent. Also I might order from him for commercial units. But you can't do business with someone that... well, doesn't do business.