Topic: GridSeed 5-chip USB miner voltage mod - page 8. (Read 156991 times)

U29 is a "dual unbuffered inverter"  http://www.nxp.com/products/logic/buffers_inverters_drivers/series/74HC2GU04.html - see the ordering tab on that same page

U9 is a low dropout regulater from UPI Semiconductor.  http://www.upi-semi.com/product/ProductInfo.aspx?ProductID=156  I couldn't find anyplace to directly order this one in the quick couple minutes I searched it, but if you can't find it, chances are TI or Fairchild or STI have something that will match the specs nearly exactly.

How did they break?

thanks for the reply they look like IC chips but I cant seem to find where to buy them anywhere.

First looks like:



Second looks like:


Hopefully you or one of the experts here know what they are because I don't.

https://www.dropbox.com/sc/49d8nddz5pq6so0/AAAxQatn8c4nHKjL9HTsbJRVa can someone tell me the value of the chip I have circled in yellow it seems the corner broke off somehow looks like its U29?

https://www.dropbox.com/sc/wv2fser9qsckrxd/AAADuFrCeExPo0daWuG4M6LGa - and I need the value of this one as well as it looks like the corner melted or broke off as well

depends on your standards
Ayouye 937+ seems to be very good rated on Amazon but goes for 50-60 bucks
you can also get an analog Weller for 100... (my ERSA was almost 150€ when i got it for bday)

usually they have ~1mm, so have to add one yourself

Accidently overheating the FB while soldering the + fan wire to it can cause pre-mature failure. It only takes a few seconds of too much heat to burn one up, I am sure.

Besides the fan is only pulling 78mA, if that while running and maybe 140mA startup which lasts less than 2 seconds to spool up and stabilize.

By the way, I forgot to mention that I revised the 5V USB Fan power mod recently. Only days ago actually. So I'm late posting it. Sue me!  
On the last few batches of pods, the fan + is now connected to and powered by 12V input via 5V regulator on the PCB.
See pic.
 

You can make the change easily if you wish to. I've been powering 6 of my miners via 5V USB for months now, for hundreds of hours straight now. No problems with the FB's! Just be very careful not to overheat the components you are keeping on the pcb.

I know I didn't overheat any of them when soldering to them. It takes me less than a second to solder the wire to the tinned connections.
All is well.

By the way, all 20 were the latest plain aluminum colored pods. All heat sinks were evenly touching their respective chips. No components were on a different plane i.e. higher than the 5 main uP chips. Looks like they got the components mounted right on this run.
See pic.


Finally, the whole unit assembled and ready to uber-hash!
See pic.

Enjoy!
And....
Peace  

I haven't been following this thread for a while but when I was, I could not find any photos of the underside of the Gridseed PCB. I took some today, hope this is useful to someone:

• Bottom of PCB (heatsink cutouts visible) http://i.snag.gy/vMaiM.jpg
• Bottom of PCB (with melted/eroded/torn heat pad!) http://i.snag.gy/IoF3t.jpg
• Bottom of PCB showing "golden pads" (cleaned up with alcohol wipe) http://i.snag.gy/chVId.jpg

Sorry they are pretty terrible quality but they should give Gridseed virgins a fair idea of what to expect when they take the bottom heatsink off.

Another pool I'm on shows a 12 hr hash rate.  Do you know what the pools you're using show? 12 hr, 24 hr or something else?  Just trying to eliminate some things here.  Running 12 hrs on a pools that shows 24hr hashrate would probably show about half what you expect.

I have run for 12 hours at a time with two different multipools and the results are the same: about exactly half the hashes I should have for my 20 seeds (have about 5M, when I should have 10M-as per controller). When I clock it back down to 850kHz the alignment matches up between contoller and pool (have 7.2M on both controller and pool).

Is anyone here running on the China-supplied silver PSUs with multiple connectors and 20 volt-mods? I wonder if the power supply may be an issue.

dyland - how long do you let them run before changing settings?
I don't use a  hashra controlla.  One pool I'm on shows 24 hr hashrate.  If I look at it after 6 hours the hash rate will be low.  After 24 hrs it is what I expect to see.

Another way to check would be the amount of coins mined per 24 hrs.

Has anyone encountered the following problem?:

I am running 20 grid seeds off a pi running hashra controlla (BFGminer). These are recently volt-modded 47.7k resistor to go about 510khsh.


PROBLEM: They are showing 510khsh on the controller, controller shows very little hw rejects at 1200, but poolside they only report about half that.

When I take I clock it back down to 800 from 1200, controller and poolside are aligned at about 340 per unit.

Thanks in advance for any help.

Radio shack has your average 25-40w (non adjustable) irons for around $14.  I don't recall if they come with a fine tip or not.  I think they sell tips for up to $5.  It's been awhile to be honest since I've looked into buying equipment. 

Actual 'stations' are much more generally.  Some come with a small number of accessories, others don't.  You could check Amazon/google to see the range.

+more I needed to hear. Thanks!

I @ new to this, how much for a decent soldering station? And does a soldering station come with a 0,5mm tip?

try to support your hands somewhere on the table of softly on the miner

i have shaky hands too but with a bit of practice and concentration i learned to handle it

remember to get a decent solder station or at least a 0,5mm tip first!

I took a look at them through the cooling fins, they are microscopic. Thank you for the advice. And yes it makes me very upset I cannot do it myself. It's so simple but yet I could trash 80 bucks down the drain for nothing in which my shaky hands will do. I got bad shaky hands.

You have any advice of any forum members willing to get payed to do it or is it just not worth it?

I'd like to say it's really easy...but that's because I've been soldering for at least 15 years, but honestly...if you're just bridging two locations, it is easy.  Just google some soldering tutorials and practice on some junk first.  Anything will do, old phone, old hard drive, etc.  Just as long as the components are small, it will give you something to practice on without the worry of ruining something. 
If you use a small piece of wire, just tin the wire with solder first, lay it across the location to bridge and touch the iron to each pad just long enough to melt the solder.  Trim off any excess and you're done.  Just remember not to use a LOT of solder.  A little goes a long way.

That's about the best advice I could give short of paying someone to do the mod (which in my opinion is actually counter-productive as you're spending yet more money). 

Ok, thanks, nst6563. I am not touching either of those, I was going to use the circuitwtriter pen, but I think the tip is to large and it might squeeze to much goo out. man i wish I knew how to solder perfectly.

I have a gridseed here unmodded that is just begging for the permanent volt mod.

It really depends.  Just bridging the one location listed in the OP then you'll need to specify voltage=1 in the command line in order to activate the higher voltage. 
If you check out this guide here https://bitcointalksearch.org/topic/guide-jesses-official-overclocking-voltmod-guide-for-g-blade-gridseeds-v2-575315 it has many pictures of the different voltmods.  For bridging the location(s), in his pics, the blue circle enables the use of the voltage=1 parameter in some mining software.  Bridging location 2 (the yellow circle) enables the higher voltage without the need of specifying the voltage=1 parameter.

one or two?

In the OP's picture I see only one green square location.

Just curious....but is the 5v USB fan mod on these gridseeds that have the failed USB ferrite bead?  It could be the added current usage of the fan stresses it enough over time to the point of failure as I'm sure the USB circuitry wasn't designed with the load of the fan in mind.  I'm not saying it can't handle it, because there is plenty of power from the USB port for a fan, but given the build quality of these things it really wouldn't surprise me.