Got the power supply section working this weekend. Be very careful in orientating parts, the mirror of the right and left supply, along with the fact that it's a bipolar supply makes things tricky. I'd also recommend testing the up to the end of the three legged regulator first, before adding the rest of the supply. It might save you some headache.
Speaking of those regulators, I was using the TI parts and ordered the KTE package, which shows on the datasheet as a three legged part. However, the ones I got were two legged, with the tab as the third. Strange. The KTT package (TO-263) fits great though.
Also, the capacitor landings are IMHO made for machines not humans. It would be nice if they were a bit longer. It's doable, but make sure the solder is wicking through the joint and not just balling up at the end of the leg.
Speaking of those regulators, I was using the TI parts and ordered the KTE package, which shows on the datasheet as a three legged part. However, the ones I got were two legged, with the tab as the third. Strange. The KTT package (TO-263) fits great though.
Also, the capacitor landings are IMHO made for machines not humans. It would be nice if they were a bit longer. It's doable, but make sure the solder is wicking through the joint and not just balling up at the end of the leg.
Indeed, I have both of those and two OPA211.
In other news, I'm getting ready to order some of the rumble filter boards. If anyone is interested, contact me via PM or post here. Hopefully, I'll have a cost on Monday. I don't want to end up with a ton of extras, so you might have to each buy two boards or something, we'll just have to see. I'll try and be fair, and just like last time, I want to buy the designer a board or two.
Given my ham fisted soldering skills i should probably have a spare board if any are going so count me in. Likewise for the rumble boards a spare never hurts.
I found the opa827 for £6 in the end so I ordered them. OPA211 would be handy though.
I actually started going through the pcb layout again yesterday and now have about half of a solder mask marked out with component numbers.
I found the opa827 for £6 in the end so I ordered them. OPA211 would be handy though.
I actually started going through the pcb layout again yesterday and now have about half of a solder mask marked out with component numbers.
excellent! I'm going to spend the morning coaxing my 4 year old back to school 
... then I'll try and get the files ready for the fab.
With regard to the amp boards, the other option is to have someone front part of the cash and in return get multiple boards. I think around $100 would be sufficient. I could hold the boards and reimburse you once they sell, or could ship them to you and let you list them in the for sale forum.. just another idea.
... then I'll try and get the files ready for the fab.With regard to the amp boards, the other option is to have someone front part of the cash and in return get multiple boards. I think around $100 would be sufficient. I could hold the boards and reimburse you once they sell, or could ship them to you and let you list them in the for sale forum.. just another idea.
Ok, looks like the boards will run $9 each. Figure $3 shipping. That includes two free (and shipping) for our gracious designer. There will be 12 boards remaining.. So, we are half way there:
1 - luvdunhill
2 - Tarasque
2 - sq#s
I'm thinking about also offering matched caps. From the designer (I hope posting this is okay):
"The DigiKey part number is 495-1122-ND and you need to match as close as possible in trios (C611, C602, C603) and (C612, C606, C607). The matching between channels can be the usual 1%. The absolute values in each trio are not critical, +/-5% is perfectly fine. Example: (1.566u, 1.564u, 1.562u) and ( 1.557u, 1.559u, 1.555u) are very good. I got 20pcs and I was able to select 12 matched caps as above, for two rumble filters but I guess I was a little lucky"
If we're interested in this let me know. I have a Fluke 287 to do the matching, I figure that will be sufficient. If you'd like to propose another cap that will fit, feel free and we can consider that option as a group.
1 - luvdunhill
2 - Tarasque
2 - sq#s
I'm thinking about also offering matched caps. From the designer (I hope posting this is okay):
"The DigiKey part number is 495-1122-ND and you need to match as close as possible in trios (C611, C602, C603) and (C612, C606, C607). The matching between channels can be the usual 1%. The absolute values in each trio are not critical, +/-5% is perfectly fine. Example: (1.566u, 1.564u, 1.562u) and ( 1.557u, 1.559u, 1.555u) are very good. I got 20pcs and I was able to select 12 matched caps as above, for two rumble filters but I guess I was a little lucky"
If we're interested in this let me know. I have a Fluke 287 to do the matching, I figure that will be sufficient. If you'd like to propose another cap that will fit, feel free and we can consider that option as a group.
unfortunately not. I ordered some of the rumble filter boards mentioned in the first few posts.
there are some rumble filter boards available. I can make up more of the amp boards if/when a suitable number of people are interested. Let's say 5.
