Group order of non-inverted LM3875 pc boards? Anyone interested?

[Alcaid]

Re: Re: Obout grounding

You have the +PGND and -PGND reversed, as I made a mistake on the silkscreen in the first picture that you have. This should be corrected on the pcbs.

As for the signal and output ground, they are tied together with a small trace under R2, so you do not need to this externally. Just use the OG and SG pads for tieing to your source and output.

The CGND connects to your chassis, central ground point, where the AC ground comes in.

--
Brian

Three questions:
1. Would switching +PGND and -PGND have any affect?
2. Why don't you just run a single ground from the bridge PCB to the amp PCB?
3. In general, should the star ground be between the power supply caps (on amp PCB) or between bridges?

 

[BrianGT]

Re: Re: Re: Obout grounding

Three questions:
1. Would switching +PGND and -PGND have any affect?
2. Why don't you just run a single ground from the bridge PCB to the amp PCB?
3. In general, should the star ground be between the power supply caps (on amp PCB) or between bridges?

1. It shouldn't have any effect, except for cosmetic reasons. It is nicer to have the + on the + side, instead of the opposite.

2. It seems better to have the main grounding point be on the pcb, with the power grounds not referenced to ground until the main power ground on the pcb.

3. In general, it shouldn't make too much of a difference, but Peter Daniel prefers this way, and it is proven to work well.

--
Brian

 

[Alcaid]

Thanks for answering.

 

[Saurav]

1. Would switching +PGND and -PGND have any affect?

I accidentally did that on a phono stage once, and the circuit started motorboating. It's quite possible that something else (or a side effect) caused it, but since then I've always made sure my grounds return to where they started from.

 

[BrianGT]

Blackgate N 4.7uF

Can anyone find a large stock of Blackgate 4.7uF N capacitors? I would really like to include them with the kit orders, but I currently only have enough to cover half the orders.

Anyone able to locate them in stock somewhere?

--
Brian

 

[SQ Kid]

i dont know if i mentioned it already, but thanks for replying to my questions. your hard work is much appreciated and congrats on the wedding (last thing to be thinking about on your wedding night is electronics... )

 

[budwiser]

Did you check with Michael Percy? He carries Black Gate.

 

[BrianGT]

Did you check with Michael Percy? He carries Black Gate.

Yes, I bought out the stock that he had on this item, and he is getting more in a couple of weeks. I will probably end up offering the option to wait a week extra, or else I will ship out the boards with Nichicon Muse caps. This is after I use the BG N 4.7uF caps that I have now to cover the first half of orders.

--
Brian

 

[BrianGT]

Re: Important Announcement

Important Announcement:

I will stop taking orders for kits (not for pcb sets) tommorrow morning, due to the large number of orders received thus far. If you want to order a kit, please submit your order before tomorrow morning.

The reason for this is that I don't want to get too backlogged in putting together kits and mailing them out. After a decent amount of kits are mailed out and I am able to source more parts for the kits, I will start taking orders again.

I am also getting married on the 27th of this month, and want to be finished all the kit orders before this time, so that I don't have to be putting kits together on my wedding night.

Orders for pcb sets will not stop, and will continue until I run out of pcbs, and have to order more.

If you miss out on the kit orders, don't worry, as I will definately offer them again in the future, since there was such a big interest in the group order thus far.

I am still working on getting all the confirmation e-mails together for the orders and will mail them out soon. I have been busy ordering parts, as I have had to order from 8 vendors to get all the parts for these orders, and am still in the process of ordering.

Drop me an e-mail if you have any questions.

One more thing: I have bought packing materials, and will start getting kits together early next week, when the last parts orders come in. I will try to have a decent amount of orders ready to ship out, when I get the pcbs a week from tommorrow (12th). If you ordered early, your order could ship out on the 15th. I will work hard to get all orders shipped out quickly.

--
Brian

I will stop taking orders for kits at around Noon (EST -5:00). After this point, I will make new Wiki to determine how much interest there is in more kit orders.

I will start taking kit orders again in a few weeks, if the interest is there.

--
Brian

 

[Variac]

These people have Black Gates. I was too tired to check if the right ones...

http://www.hndme.com/storecapblackgate.html

 

[BrianGT]

Re: Important Announcement

Important Announcement:

I will stop taking orders for kits (not for pcb sets) tommorrow morning, due to the large number of orders received thus far. If you want to order a kit, please submit your order before tomorrow morning.

The reason for this is that I don't want to get too backlogged in putting together kits and mailing them out. After a decent amount of kits are mailed out and I am able to source more parts for the kits, I will start taking orders again.

I am also getting married on the 27th of this month, and want to be finished all the kit orders before this time, so that I don't have to be putting kits together on my wedding night.

Orders for pcb sets will not stop, and will continue until I run out of pcbs, and have to order more.

If you miss out on the kit orders, don't worry, as I will definately offer them again in the future, since there was such a big interest in the group order thus far.

I am still working on getting all the confirmation e-mails together for the orders and will mail them out soon. I have been busy ordering parts, as I have had to order from 8 vendors to get all the parts for these orders, and am still in the process of ordering.

Drop me an e-mail if you have any questions.

One more thing: I have bought packing materials, and will start getting kits together early next week, when the last parts orders come in. I will try to have a decent amount of orders ready to ship out, when I get the pcbs a week from tommorrow (12th). If you ordered early, your order could ship out on the 15th. I will work hard to get all orders shipped out quickly.

--
Brian

Last call for kit orders! I will disable the option of ordering kits on the order page in a couple of hours. I will keep the option of ordering pcbs up on the page still.

All parts have now been ordered for the kits, as the paypal funds made the transfer. I will start assembling kits early next week, and when the pcbs come at the end of the week, I can begin packaging. I am hoping to get a decent sized batch of orders out on Monday, the 15th, assuming that no delays occur from the parts shipments or pcb shipments.

Note: If you already placed an order, and wish to modify the order, I will allow for this. Simply drop me an e-mail.

--
Brian

 

[BrianGT]

A little over an hour left for orders to be submitted...

--
Brian

 

[jtsjf]

Well, I'm still interested but paypal is taking FOREVER to transfer money so I can pay you. Well, the pcbs are what I was initially interested in anyhow. Hey, this way I can buy more pcbs and flesh them out (so to speak) over a longer time...heh....

Brian, Thanks for doing this- your hard work is very much appreciated.

Cheers,
Jason

 

[BrianGT]

I have stopped accepting kit orders at this time. Kits should be offered again in a month or so.

I will continue to take orders for pcbs.

--
Brian

 

[Lee35210]

Honeymoon

Hey Brian,

I hear the Scottish Inn near 6 Flags is real purty!
Can always use a few new 'Wrecks

Best of luck and thanks again!

Lee35210
(L'il wreck in early 50's, had my 1st real food at The Varsity)

 

[moe29]

My Dad was at Emory in the early 50's, and frequented the Varsity

He was at the Gradys Hospital too... but as Dr. not a patient

3 generations of my family have eaten there

The ATL rocks!

Good Luck Brian! and Congrats (and thanks for the fab GP)

 

[Variac]

real food at The Varsity

This is arguable -I've been there. It's a cool place though- I have their t-shirt!

 

[BrianGT]

My Dad was at Emory in the early 50's, and frequented the Varsity

He was at the Gradys Hospital too... but as Dr. not a patient

3 generations of my family have eaten there

The ATL rocks!

Good Luck Brian! and Congrats (and thanks for the fab GP)

I can handle the varsity about once year, as it take me a couple of days to recover from all the grease that it contains. I lived one block from it freshman year (right over the interstate, closest dorm to it), and after going there a few times in a short period, I just felt like I couldn't go there for a long time.

I love their onion rings and frosted orange though.

The key to the varsity is to take it moderation.

--
Brian

 

[Lee35210]

I couldn't eat there now without a double Protonix chaser!
Last time I ate there was when I took my Dad to a game @ Grant's Field in the early '80's. I think that was his first time since he was @ Tech in the 50's. Oh how we drift when we start to age!
I have no idea what this has to do with GC's!?!

 

[dp]

AAaaahhhh!

So I spent the afternoon sifting through the 23 page thread and at the end find out I'm a day late. Servers me right for taking diyaudio out of my favourites file at work (in an attempt to actually do more work).

Brian, if you've got the parts to put together another 2 kits, I'll take them. Otherwise, put me down as interested for another run of ordering whenever you get it started up again.

-duane