Helium
-
Posts
121 -
Joined
-
Last visited
Content Type
Profiles
Forums
Events
Posts posted by Helium
-
-
@Laowei: Just curious, what GG board file are you using?
What I'm looking at has slightly different traces layout (was posted 20160224). Can you check yours if its newer?
-
Yep I'm working for Japanese company, and my eyes got used to seeing that)) whoever edited the file has OS with japanese language pack installed.
-
1
-
-
Ok, I checked BOM and availability of parts here and there and it seems feasible to build but at enourmous price, almost prohibitive for own use.
I guess ttl quantity of listed obsolete parts in whole universe is enough to build 10 units more of this thing. Maybe 15 (provided they are not 'wasted' for other projects). Then they will be depleted forever.
I may be missing somehow but last year you mentioned:
=====
diy-t2 with current production parts testing now obsolete fets 2sj79/2sk216 replaced with ksa1220/ksc2690 and 2sa1486 replaced with stn9360
=====
How about the progress? I guess board have to be redesigned to accomodate new parts.
-
1
-
-
1 hour ago, kevin gilmore said:
Thank you so much.
Curious, japanese fonts are used, who touched
Thank you so much!
-
Kevin, could you please upload the latest BOM (both amp and ps) of DIY T2?
Could not find it anywhere.
-
I think he needs to try another opamp instead of opa445. Maybe DC must be decreased temporarily for another lower voltage opamp, but worth to try.
-
On 31.08.2017 at 3:16 AM, gepardcv said:
I ordered the Phoenix "PT 1,5" series terminal blocks which we discussed earlier. While it's nice that they have plastic along the bottoms, I'm not convinced they would help prevent arcing if a trace passes beneath the attached wire. (1) There is still no plastic right where the trace would run. (2) There is no plastic directly beneath the wire attachment. It's beyond me why there just isn't a fully-enclosed plastic housing here. Maybe it's another Phoenix part number which I haven't found yet. Photo attached.
Why do you guys always refer to 5-mm pitch connectors while the board has 5.08-mm pitch?
-
23 minutes ago, Pars said:
don't think the board will fit an Alps RK27 pot
Sh*t, I confused Alpha with Alps. Then TKD definitely better of course. Just place order for Alpha version, will contact PCB maker to replace Gerber.
-
Yes, it's 4,8 x 6,8, and latest rev is 1.5.
What's input impedance of 'portable' Dynalo? If it's low, then problem is that 5K RK27114 Alps hard to source, even on Ebay (they seem to disappear completely).
-
On 23.09.2016 at 1:52 AM, kevin gilmore said:
final board file for the transportable just posted
http://gilmore.chem.northwestern.edu/boards/SSDynalo-v1-4.zip
this is Kerry's work, very amazing
What is exact board dimension of this PCB?
On 02.11.2016 at 4:45 AM, Kerry said:I did a small update on the mini board to add a pad on the opposite side of the on board regulators.
Here's and updated view...
Hi Kerry. Is SSDynalo-v1-4.zip from Kevin's depository the latest gerber?
EDIT: Found, never mind.
-
2
-
-
wow thank you!
-
Grounded Grid?
-
On 04.09.2017 at 5:31 PM, kevin gilmore said:
power supply ground is signal ground and has to be connected.
/
-
On 10.05.2017 at 8:25 PM, spritzer said:
Given Kevin's retirement, we had to move the files so I put them here temporarily. I might move them again soon though....
Could you upload there schematic files as well please?
-
Kevin,
Want to build this board and try it instead of e12. Few questions if you allow:
Is trigger offset DC with standard resistors 0.5v? Is it from O+ to O- or from O+ to GND/O- to GND?
Is it suitable for non-differentail balanced amps like 4-board B22, 2-board KSA5?
Is it suitable for SE amps (like 2-board B22, 1-board KSA5)? Just use R+ and L+ terminals?
Input GND taken from where? If it's signal GND, then take it from any board? Can it be left unpopulated?
-
Thanks.
-
Hi Kevin, is KA5 fully-differential amp? I guess it's not, want to make sure.
If it's not, then for balanced operation 2 boards are needed, and one board amplifies any 2 signals from L+ L- R+ R-. Is it correct?
-
What is exact board size of balanced Dynahi with onboard heatsinks (aka dynahibal8f)?
-
Can someone please explain what AT1000 data is?
Is it related to Amprobe AT1000 tracer?
-
Kevin, is this thread all devoted to goldenreference4.zip?
What about goldenreference and goldenreference3? Is goldenreference4 direct replacement for those?
And you opted to get rid of TO-3 transistors?
-
On amb's site, he only states that 1 e12 per PSU should be used, which I'm not quite sure I understand the rationale for.
It's because e12's virtual ground is referenced to PS ground. Imagine you are using 2 sigma22 and only 1 e12, which is referenced to one sigma22. Even if you built both sigma for the same voltage, due to parts tolerance the DC voltage of both will not be identical. Even 0.1v difference of sigmas output will make e12 false trigger because it will think that DC offset is 0.1v+amp's native DC offset.
-
If I use a protector board the only cut of point is 0.5v. Isn't that too high already? Does anyone know any design that cut off below 0.5v? What is the safe cut off point for headphone?
Try AMB's e12. I'm using it in almost every build of beta22, and will use for dynahi as well.
To my opinion, 0.5v is too large and may damage some headphones, while others will survive. Anyway, I wouldn't risk my collection of 1000-1500USD headphones. I want the amp to be as most universal as possible.
-
Ordered off board version of golden reference boards from seeedstudio 1.6mm 2oz copper
Will have some extras for grab when my order gets here.
Kevin, are Golden reference boards finalized? You mentioned that there is oscillation unless some parts are not omitted...
-
Sorry going to order for myself only, no experience to start GB if you meant it. Also, it's going to be rather expensive. The price of PCB house I've used to deal with is around 18-20USD per PCB of Goldenreference for the lot of 4 (180x110mm, double layer, FR-4, 1.5mm, 70um).
The Multi Amp aka Dynalo Mk2
in Do It Yourself
Posted
It might be transistors are heating THAT340 thru copper layers. Are they soldered directy to board, or plugged in sockets?