n_maher Posted March 24, 2009 Report Posted March 24, 2009 I hate heat sinks with pins, good call to go with a mechanical fastener. Personally I use #4 screws (I'll fight metric to my irrational deathbed) but I'm sure the M3's work fine too.
PICaudio Posted March 24, 2009 Report Posted March 24, 2009 The diameter of the hole it's perfect for a M3 tap -- o -- Rodrigo
Smeggy Posted March 24, 2009 Report Posted March 24, 2009 Nice, threadded sinks seem like an obvious upgrade.
Icarium Posted March 26, 2009 Report Posted March 26, 2009 Last call on SumR 260VA toroids.. I'll probably make the order next week so if you are interested please let me know as soon as possible/convenient. I believe luvdunhill is collecting payments on cinemags right now so if you haven't heard from him please contact him.
Icarium Posted March 27, 2009 Report Posted March 27, 2009 K heard back from vvs for Dreadhead and looser101.. looks like we have a total of ~9 xformers right now. Shooting for 10.
justin Posted March 27, 2009 Report Posted March 27, 2009 FAIL unless you've already received a prototype from SumR and tested it with the PSU and Dynafet amp
Icarium Posted March 27, 2009 Report Posted March 27, 2009 Yeah luvdunhill is going to be ordering an initial prototype one. Like the actual complete order may not happen immediately next week. Just want firmer #s when talking with them. Actually amend that to 8 not 9.
j4cbo Posted March 27, 2009 Report Posted March 27, 2009 justin: Of all the possible part interactions to worry about, this doesn't seem like the most worrying one to me...
Pars Posted March 27, 2009 Report Posted March 27, 2009 Ya know, if you want to hold off on the SumR's until a proto is built, I probably won't be using the 120VA 2x30V fully shielded SumR I have for awhile. Someone is welcome to use it to test with as long as I get it back in the same condition that it leaves here in
Icarium Posted March 27, 2009 Report Posted March 27, 2009 Nod I think luvdunhill and Kevin Gilmore are our two prototypers. New release candidate this weekend I think is the goal
DigiPete Posted March 27, 2009 Report Posted March 27, 2009 Nod I think luvdunhill and Kevin Gilmore are our two prototypers. New release candidate this weekend I think is the goal So luvdunhill and KG are going to build up the first boards for test? That cool. When everything is settled, I will assemble the passive parts order.
Icarium Posted March 28, 2009 Report Posted March 28, 2009 Yeah but the boards havent been ordered yet.. btw since Luvdunhill has transistors already for these prototypes the people prototyping can start building as soon as those are ordered and passive parts are procured for these builds (Not the main passive parts order). What I am going to do is combine the cost of prototype parts/boards and distribute that to everyone when we do the main board order... does that sound reasonable/acceptable? The idea is these guys are donating their time/labor so they shouldn't have to pay for parts/boards and their work benefits the group. It shouldn't be very expensive divided over 10 people or so.
luvdunhill Posted March 28, 2009 Author Report Posted March 28, 2009 So luvdunhill and KG are going to build up the first boards for test? That cool. When everything is settled, I will assemble the passive parts order. I'd recommend prototyping with the actual passive parts that are going to be provided in the kit. So, it would be helpful to have a BOM I think. I believe both you and Jacob may be working on one?
DigiPete Posted March 28, 2009 Report Posted March 28, 2009 I'll try to come up with something this weekend
DigiPete Posted March 28, 2009 Report Posted March 28, 2009 Do we have a validated final schematic with correct part numbers?
DigiPete Posted March 28, 2009 Report Posted March 28, 2009 Guys, Here is the resistor BOM as it now stands based on the latest schematic. If these are the correct values and numbers, I will source various parts and present a final proposal to the group. I would say everyone gets the same parts, guys who want custom resistors or caps, either go it alone, or buy the whole pile of parts (resistors, caps, leds, trimpots, teminal blocks and ICs). Trying to keep it affordable and manageable. What say you? Ok, now getting some feedback from y'all on parts selection: What values are R59 and R62 ? Is 1M the correct value for R63? Xicon for the 2 and 5 ohm from Pars BOM. RN60D for the rest (will those fit?), but I can put in PRPs for critical signal path resistors, you guys tell me which ones to put PRPs in for. For Caps there are alot of ?? in the schematic. For rail caps is everyone ok with 470uF? What is the lead spacing and diameter limit for them? i'm calling them C3-C8, hope that's correct. How about P10352-ND Panasonic FC , or Nich UPW? Boutiques like Nichi Gold Tune or Elna Silmic II, or ?? What bypass caps do you want (i'm calling them C13-18)? Are there six bypass caps on the board, could not tell? How about 399-5442-ND CAP FILM Kemet MMK .47UF 63VDC 5MM 495-2560-3-ND Epcos MKT .47UF 63VDC 5MM 75-MKT1817447064 Vishay Roederstein .47UF 63VDC 5MM Vishay BC or Wima MKS2 ?? C19? C20 and C21?? C9 and C10 for the voltage regs to the alternate OP amp. I assume the prototype board testers will determine if another opa will be used and if these will be populated, and by what. C1 10pFSilver Mica C2. 047uFmet polyest film
DigiPete Posted March 28, 2009 Report Posted March 28, 2009 Hmmm... the tables didnt come out right....
digger945 Posted March 28, 2009 Report Posted March 28, 2009 I think it's safe to say C9 and C10 can be .1uF 50V with small lead spacing, say .1"/2.54mm. They will need to be populated regardless of opamp choice, with or without regulators. .1uF is used in some of the example circuits for the 445 at ti.com and was the value for the servo on the Dynahi.
DigiPete Posted March 28, 2009 Report Posted March 28, 2009 I think it's safe to say C9 and C10 can be .1uF 50V with small lead spacing, say .1"/2.54mm. They will need to be populated regardless of opamp choice, with or without regulators. .1uF is used in some of the example circuits for the 445 at ti.com and was the value for the servo on the Dynahi. thanks!
DigiPete Posted March 28, 2009 Report Posted March 28, 2009 RN55D if the lead spacing is 0.3". Will these 1/8 watters work for all positions mentioned above, except the 2 and 5 ohm?
digger945 Posted March 28, 2009 Report Posted March 28, 2009 I think so, being the same part as CMF55 they should be good to 1/4 watt within specs. I just put a RN55D in the calipers and I get .246" length on the body. This might work for the 5 ohm.
DigiPete Posted March 28, 2009 Report Posted March 28, 2009 This might work for the 5 ohm. An RN55D? I guess, if the power dissipation is around 1/4w or less...??
digger945 Posted March 31, 2009 Report Posted March 31, 2009 Are you sure those small caps are 5mm lead spacing, I measure 3mm. 7.5mm on the 6 big polars.
DigiPete Posted March 31, 2009 Report Posted March 31, 2009 Are you sure those small caps are 5mm lead spacing, I measure 3mm. 7.5mm on the 6 big polars. I guess if I print out those pcb pictures maybe they will be to scale, and I can measure the pitch?
Pars Posted March 31, 2009 Report Posted March 31, 2009 Access to the Eagle files would take care of that issue...
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