bdinnev

Thanks to a few people on here, I managed to dodge getting boards made and managed to buy existing boards for all the bits I need. I am still waiting on a delivery tom come in over the next week or so with the CFA boards and a few other bits and bobs but have received some GRLV boards and a set of v1 attenuator boards and a v2 board. I have done some SMD work in the past with the soldering iron but thought I would up my game this time round and give a hot air rework gun a go. Kerry sent me 2 v1 attennuator boards - 1 already populated and one bare, as well as all the parts to build it, so I finally pulled my finger out today and built it up -

Going through the various files and looking at them in a gerber viewer, .47 is goldenreference6drflipto220.zip. .48 seems to be the latest Kevin version which is the goldenreferencelargecap.zip and then v2(?) seems to be the Kevin + Kerry version.

Hi All, I have been going cross-eyed of late poring through the various threads for the projects required to get a complete amp together and hoping to get a few pointers. I was originally looking at building a Dynalo based amp but after some feedback from Pars and others I had a look at the CFA2/3 boards and think I have decided to go with a CFA3 based build. I am going to build a balanced in / balanced out setup in dual mono so for the amp boards, it will be 2 x CFA3 (based on 89753654_cfp3rssfixedssw-CADCAM.zip) - I am pretty comfortable that this seems to be the most recent version of the CFA3 board. Where things seem to get a bit interesting is the GRLV power supply. Reading through the thread, there seems to be quite a few evolutions of this design and a few different ways of completing it. Based on the GDrive archive, goldreference6d.zip seems to be the way to go but looking through the thread for it, there are a number of evolutions of the design since then including a large cap version and options for 6min/6plus, 7min/plus, 79xx/78xx etc etc - the head starts to swim when going through it. Taking a KISS approach, what is the easiest board to build in this regard especially considering effort / perfomance . Lastly, just to make the build that little more complicated, I am going to go with dual digitial attenuators. My first thoughts were to go with the delta 1 board but then I stumbled upon the digital attenuator designs here by Kevin and Kerry. The through hole version looks easier to make but is a 6 layer board which is not the cheapest to get made in small volume. The SMD version looks better but it is 3 layer which most of the small run PCB houses do not seem to support and from memory there may be a component or 2 that have to be done with a oven / hot air due to solder pads that are not accessible. Should I just stick with the delta1? Lastly, I am happy to go off and get a bunch of boards made for each however if anyone has any boards they are willing to part with that will definatly steer my decisions. Most board hoauses seem to do qty's of 5 or 10 and with me requiring 2 of everything, 5 is a shitty number as having 1 board left over does not help my minor case of OCD so I will get 10 of each made - I may use 4 of each so will have a few left over if anyone wants any (note, this is not a group buy, once decided upon, I am not going to wait for people before placing an order, I will order them and if anyone is interested down the track I should have some). Any tips would be appreciated. Cheers, Ben

Thanks for the pointers Pars - I had overlooked the LED's on the Schematics (too many hours staring at the screen!) I will take a look at the CFA projects and see which way I go. I was going to use either the GRLV of a sigma22 power supply, the sigma 22 is easy as there are kits available "off the shelf" but kinda makes sense to go with the GRLV to keep everything the "same"

Hi All, I am looking at building a dynalo SMT/SMD system, balanced in / balanced out. I have been through this thread back to front as well as the staxmafia thread etc. I think I have got the most recent gerber files (dynalobal17) as well as the schematic (kgdynalobalssproduction.PDF) and I have started building a BOM but have stumbled on a few things that I was hoping some may be able to assist with? Looking at a few comments, all resistors are 0805 size but I am not really sure of current size etc (have shot for 200mw .1% 25ppm at the moment). The schematic does not line up with the pcb with regards to the caps - the schematics only shows 3 (from memory) whereas the pcb shows as many as 12 documented with values - is there an updated schematic? Or am I using an outdated gerber? There appear to be a couple of caps on the PCB that have no values - any hints? (see attached pics) Or are these for something else? Is there a bom available anywhere? I see reference to a xls in a few placed but cannot find the file - am scratching my head on what caps, trim pots, part size for SMD transistors etc Is this project no longer active / am I barking up the wrong tree? It looks like a great project, but maybe there is a newer project I should be looking at? Cheers, Ben