Since we need not only IRF9610 and IRF610 we will have to order from Farnell or RS anyway. Some parts they sell only in hundreds, which would be no problem when group-buying. But who would want to do the work?
I suggest we group-buy only transistors & ICs, maybe some special caps as well as the diodes. But nobody could sort all those resistors.
Gruß
Christian.
I suggest we group-buy only transistors & ICs, maybe some special caps as well as the diodes. But nobody could sort all those resistors.
Gruß
Christian.
X-Aleph PCB`s arrived TODAY!
Hello again to everybody,
I guess some of You are already nervous - I have the cure for You - take a look here - I have attached a picture 
:
http://www.diyvideo.com/forums/showthread.php?s=&postid=328774#post328774
I try to find time to pack and send out everything before this weekend!
http://www.diyvideo.com/forums/showthread.php?s=&postid=328770#post328770
If somebody from this PCB-group buy is interested, let me know soon - I could hold back Your PCB shipping and combine the PCB shipping with diodes.
Hello again to everybody,
I guess some of You are already nervous
- I have the cure for You - take a look here - I have attached a picture :http://www.diyvideo.com/forums/showthread.php?s=&postid=328774#post328774
I try to find time to pack and send out everything before this weekend!
regarding parts - I have a bunch of nice very high-power (real!) dual Schottky diodes for sale - great for X-Aleph projects as rectifier bridges - take a look at this thread if You`re interested :
http://www.diyvideo.com/forums/showthread.php?s=&postid=328770#post328770
If somebody from this PCB-group buy is interested, let me know soon - I could hold back Your PCB shipping and combine the PCB shipping with diodes.
Hello everybody,
It wasn't too difficult to find the parts list at the aleph wiki page.
But it came to my mind that we all will need huge transformers as well as decent heat sinks. Both items may be much cheaper when bought in large numbers.
If you are interested I could organize the group order concerning torodials and heat sinks (the heavy stuff) but CAN NOT do this for the transistors because I have no possibilities (as well as no glue) to measure/match them.
I can imagine buying heat sink chassis, too (look at www.schuro.de for example). What size of heat sink and transformer will be needed?
Cheers
Christian.
It wasn't too difficult to find the parts list
at the aleph wiki page.But it came to my mind that we all will need huge transformers as well as decent heat sinks. Both items may be much cheaper when bought in large numbers.
If you are interested I could organize the group order concerning torodials and heat sinks (the heavy stuff) but CAN NOT do this for the transistors because I have no possibilities (as well as no glue) to measure/match them.
I can imagine buying heat sink chassis, too (look at www.schuro.de for example). What size of heat sink and transformer will be needed?
Cheers
Christian.
Me also would be interested in heavy duty, high quality torodials group purchase but I think there are two serious issues with this:
first: I believe the different transformer power and secondary voltage rating needs for each individual XA-builder will vary too much. Usually You can get good prices only for ONE specific model - not for 5 ore more different versions.
second: a torodial transformer group purchase would only make sense when the tranformers could be shipped directly from the factory to each participant of the group purchase - what I doubt is possible. Otherwise the costs for shipping and reshipping this heavy stuff very likely will eat up the savings due to the group purchase.
I`d be in in buying a reasonable lot but I doubt that anyone has the time to match a couple of hundret groups of FET`s out of a couple of thousends lot.
We have 200 boards here - if each is stuffed only with the minimum 4 FET/board - that`s 800 FET`s minimum - to get such an amount of matched FET`s I guess we would need estimated 1000 pcs. minimum (from same batch/manufactorer).
Thoroughly matching suitable groups of FET`s must take weeks (don`t forget that each FET should settle in temperature before making reliable measurement) - I seriously doubt that anyone has the time (not to speak from patience) to do this.
I believe, to achieve this in reasonable time without a special (semiautomatic) test rig which can measure a lot (say 50 pcs.) at once is quite hopeless.
BTW: I begin packing PCB`s now and hope to be able to ship out tomorrow
Hello,
I am not too sure that we would not save money by group-ordering the heavy stuff despite the additional shipping costs.
There are reasonably offerings from 10 pcs., so we could offer e.g. two different torodials.
Concerning the Transistors: I thought the person who will match transistors for a number of interested people will get a fair payment for doing it.
Regarding transistor prices: I would not like to order at reichelt. Once, I ordered a dozen TL431 and got three different types! (different manufacturers as well as TL431A, TL431C ...)
I also would wish to order everything from ONE or maybe two suppliers just to keep it simple. In the case of everybody is ordering her/himself shipping cost is another issue.
But even in this case we could share ordering numbers
Cheers
Christian.
I am not too sure that we would not save money by group-ordering the heavy stuff despite the additional shipping costs.
There are reasonably offerings from 10 pcs., so we could offer e.g. two different torodials.
Concerning the Transistors: I thought the person who will match transistors for a number of interested people will get a fair payment for doing it.
Regarding transistor prices: I would not like to order at reichelt. Once, I ordered a dozen TL431 and got three different types! (different manufacturers as well as TL431A, TL431C ...)
I also would wish to order everything from ONE or maybe two suppliers just to keep it simple. In the case of everybody is ordering her/himself shipping cost is another issue.
But even in this case we could share ordering numbers
Cheers
Christian.
Aleph-X Components Group Buy in Germany
Dear all,
May I add my 2 cents worth to the discussion.
I bought 100 IRFP044's (not 044N's from Reichelt) indirectly from IR, all from one wafer lot (with luck, was no guarantee), matched 25 of them during Christmas, picked 4 (not the best) and bulit a standard Aleph-X using Grey's schematics but with 1A bias per transistor (source resistor 0R47) and cheap parts from Reichelt otherwise just to test PCB, etc. Power supply was just standard bench supply from Reichelt. The 9610's were also from the same lot, matched at room temperature at both 10 and 20mA. I took again a pair at random.
It ran first time without trouble, no swapping, nothing; actually too easy as I don't know what else trouble to expect if I were to go for a higher power version. At startup absolute DC on both outputs to ground was about 2V, dropping to around 0.2V after 30 minutes. Differential DC was never more than 20mV and most of the time around 2mV. Transistors were matched at working current and temperature (put them in the oven first helped).
So obviously the matching was OK, but I am currently trying to develope a method to test entire curve from 0.25A to 1.5A, with reasonable effort. It would take a while (unlikely before Easter) but if it works, I would be prepared to offer the rest as matched sets (of 4 or 8) at a reasonable cost (believe me, you would never be able to afford my salary, so I am just doing this for fun and not for money) after I take the first 33. If someone lives nearby (east of Stuttgart) and volunteer to help, he gets to choose the next set of 8 at cost.
In a blind test with 6 people, including 2 amateur musicians, the AX, as it is (8W), came out on top, slightly better than JLH 15W (2 amps driven as differential through a phase shifter, see JLH Letters to the editor 1970), and both beat my Krell KAV300i by a distance despite lack of power, and hence base control. Female vocal was particularly the strength of AX (Shirley Bassey came to live 1m away). So I am totally convinced. Thank you very much Mr. Pass.
For one or two amps, most components one can find from Reichelt, Schuro, or Farnell, be it more expensive than if you buy 1000 from a distributor. For me, the one component I am having most difficulties with are the 3W source resistors. Of course you could use the MOX 4W from Intertechnik (which is what I use for the prototype), but I would love to try Vishay Dale CPF3 metal film. Under 1 ohm, they are next to impossible to get ex-stock. Minimum order quantity is 5000, and I guess they would cost around 20 Euro per hundred at that quantity, plus post plus MwSt. I want to use 0R39 instead of 0R47, to give it a bit more bias (see Nelson's article on matching) at 20V rails. My heatsink would be large enough to give 15 degC rise above ambient. If there would be sufficient people interested (say 50 people and everyone take 100) so that we can get to 5000, I would be prepared to do all the ordering and accounting, etc. Unless someone else would volunteer, to my greatest pleasure.
The other alternatives would be :
a) to use MFS3 5% from Welwyn at around the same price with 600 minimum,
b) to use 3 x 1.2ohm 2W 5% in parallel from Reichelt, which would cost 27 cent and give you better tolerances at the same time, at the cost of a bit more real estate on the PCB (probably won't all feed onto the standard board.
My preference at the moment is still Vishay, so please let me know if there is sufficient interest for a group buy. Don't send me emails please as I would have no time to check them all and you would be keeping me from my matching activities. Just post to the forum and I shall check every now and then when I have time.
The rest is difficult to do together, as people might want to use different rail voltages and different number of devices in parallel.
One thing to watch is the power supply capacitors. If you intend to use CRCRC, say 44000uF as C and 0.22ohm as R, you would get more than 35 amps peak charging current, which equates to some 15A rms, for the first C, very close to if not exceeding the maximum rating (for 3000 hours) for most large caps. So you might wish to consider parallel small caps (say 20 x 2200uF) through current balancing resistors.
There are enough threads on the forum on rectifier diodes, input caps, etc., so I am not going into that.
Patrick
Dear all,
May I add my 2 cents worth to the discussion.
I bought 100 IRFP044's (not 044N's from Reichelt) indirectly from IR, all from one wafer lot (with luck, was no guarantee), matched 25 of them during Christmas, picked 4 (not the best) and bulit a standard Aleph-X using Grey's schematics but with 1A bias per transistor (source resistor 0R47) and cheap parts from Reichelt otherwise just to test PCB, etc. Power supply was just standard bench supply from Reichelt. The 9610's were also from the same lot, matched at room temperature at both 10 and 20mA. I took again a pair at random.
It ran first time without trouble, no swapping, nothing; actually too easy as I don't know what else trouble to expect if I were to go for a higher power version. At startup absolute DC on both outputs to ground was about 2V, dropping to around 0.2V after 30 minutes. Differential DC was never more than 20mV and most of the time around 2mV. Transistors were matched at working current and temperature (put them in the oven first helped).
So obviously the matching was OK, but I am currently trying to develope a method to test entire curve from 0.25A to 1.5A, with reasonable effort. It would take a while (unlikely before Easter) but if it works, I would be prepared to offer the rest as matched sets (of 4 or 8) at a reasonable cost (believe me, you would never be able to afford my salary, so I am just doing this for fun and not for money) after I take the first 33. If someone lives nearby (east of Stuttgart) and volunteer to help, he gets to choose the next set of 8 at cost.
In a blind test with 6 people, including 2 amateur musicians, the AX, as it is (8W), came out on top, slightly better than JLH 15W (2 amps driven as differential through a phase shifter, see JLH Letters to the editor 1970), and both beat my Krell KAV300i by a distance despite lack of power, and hence base control. Female vocal was particularly the strength of AX (Shirley Bassey came to live 1m away). So I am totally convinced. Thank you very much Mr. Pass.
For one or two amps, most components one can find from Reichelt, Schuro, or Farnell, be it more expensive than if you buy 1000 from a distributor. For me, the one component I am having most difficulties with are the 3W source resistors. Of course you could use the MOX 4W from Intertechnik (which is what I use for the prototype), but I would love to try Vishay Dale CPF3 metal film. Under 1 ohm, they are next to impossible to get ex-stock. Minimum order quantity is 5000, and I guess they would cost around 20 Euro per hundred at that quantity, plus post plus MwSt. I want to use 0R39 instead of 0R47, to give it a bit more bias (see Nelson's article on matching) at 20V rails. My heatsink would be large enough to give 15 degC rise above ambient. If there would be sufficient people interested (say 50 people and everyone take 100) so that we can get to 5000, I would be prepared to do all the ordering and accounting, etc. Unless someone else would volunteer, to my greatest pleasure.
The other alternatives would be :
a) to use MFS3 5% from Welwyn at around the same price with 600 minimum,
b) to use 3 x 1.2ohm 2W 5% in parallel from Reichelt, which would cost 27 cent and give you better tolerances at the same time, at the cost of a bit more real estate on the PCB (probably won't all feed onto the standard board.
My preference at the moment is still Vishay, so please let me know if there is sufficient interest for a group buy. Don't send me emails please as I would have no time to check them all and you would be keeping me from my matching activities. Just post to the forum and I shall check every now and then when I have time.
The rest is difficult to do together, as people might want to use different rail voltages and different number of devices in parallel.
One thing to watch is the power supply capacitors. If you intend to use CRCRC, say 44000uF as C and 0.22ohm as R, you would get more than 35 amps peak charging current, which equates to some 15A rms, for the first C, very close to if not exceeding the maximum rating (for 3000 hours) for most large caps. So you might wish to consider parallel small caps (say 20 x 2200uF) through current balancing resistors.
There are enough threads on the forum on rectifier diodes, input caps, etc., so I am not going into that.
Patrick
It`s done.......
and I´m glad it`s (almost) over
Yesterday I have packed almost everything (unless two people who have requested to still hold back their boards) and shipped out today (as at Saturdays the post office is extremly crowded anyway the officer wasn`t exactly happy that I caused an even huger queue).
So I hope that everything arrives well
, I think everybody should get his boards before the next weekend at the latest (most will arrive earlier).
So I wish all of You much fun and good luck with Your projects and ......let`s show Your works!!
and I´m glad it`s (almost) over
Yesterday I have packed almost everything (unless two people who have requested to still hold back their boards) and shipped out today (as at Saturdays the post office is extremly crowded anyway the officer wasn`t exactly happy that I caused an even huger queue).
So I hope that everything arrives well
, I think everybody should get his boards before the next weekend at the latest (most will arrive earlier).So I wish all of You much fun and good luck with Your projects and ......let`s show Your works!!
Everything posted ?
Christoph (Coculino),
Ulrich (who is a colleague) from Ulm has ordered 10 boards. He just left Friday for Thailand for 3 weeks' holiday. If his package bounds back from the post after one week, you know why, and please hang on to it and send him a email.
I don't have authorisation to fetch his post, and his lives 80km from where I do, so there is little I can do.
Sorry for the trouble,
Patrick
Christoph (Coculino),
Ulrich (who is a colleague) from Ulm has ordered 10 boards. He just left Friday for Thailand for 3 weeks' holiday. If his package bounds back from the post after one week, you know why, and please hang on to it and send him a email.
I don't have authorisation to fetch his post, and his lives 80km from where I do, so there is little I can do.
Sorry for the trouble,
Patrick
To those getting their new AX boards.
If you're a Cardas fan, the 2nd annual Cardas bulk purchase is just starting to pick up steam. If you're interested see this thread in the trading Post Forum and the WIKI Page for details.
I have already sent 100 price lists out.
Hi Christoph,
Sorry to spam you like this. I'm sure you'll understand.
If you're a Cardas fan, the 2nd annual Cardas bulk purchase is just starting to pick up steam. If you're interested see this thread in the trading Post Forum and the WIKI Page for details.
I have already sent 100 price lists out.
Hi Christoph,
Sorry to spam you like this. I'm sure you'll understand.
More Spam
Thanks Patrick - good to know!
Ulrich`s board where shipped letter post (uninsured - so no need to sign anything) and in case they fit in his mailbox there will be no problem.
If it bounce back though, I`ll keep it until Ulrich is back and I`ll email him.
I hope not more of You guys are in Thailand (though I can understand this well ......the weather is just too fine there ) I was so glad to get all the stuff out and I wouldn`t really want to see coming half of it back
Rodd,
no problem at all here.........in fact...I really appreciate all the bulk purchase things and other offers that are going on here increasingly.....there is no better way to save on money!
.... and actually this is a good opportunity to place some spam myself
.....
Folks, I hope You don`t really mind when I draw Your attention on this thread again:
High-Power, High-Voltage Dual Schottky diodes for sale
I have already lots of requests and orders from all over the world (and as it appears I`ll sell all of them) but oddly enough none from Germany what makes me really wonder - so much X-Aleph boards...
I believe You won`t find anything better (and more handy than those) at a better price.
Now that`s enough spammed.
Thanks Patrick - good to know!
Ulrich`s board where shipped letter post (uninsured - so no need to sign anything) and in case they fit in his mailbox there will be no problem.
If it bounce back though, I`ll keep it until Ulrich is back and I`ll email him.
I hope not more of You guys are in Thailand (though I can understand this well
......the weather is just too fine there ) I was so glad to get all the stuff out and I wouldn`t really want to see coming half of it backRodd,
no problem at all here.........in fact...I really appreciate all the bulk purchase things and other offers that are going on here increasingly.....there is no better way to save on money!
.... and actually this is a good opportunity to place some spam myself
.....Folks, I hope You don`t really mind when I draw Your attention on this thread again:
High-Power, High-Voltage Dual Schottky diodes for sale
I have already lots of requests and orders from all over the world (and as it appears I`ll sell all of them) but oddly enough none from Germany what makes me really wonder - so much X-Aleph boards...
I believe You won`t find anything better (and more handy than those) at a better price.
Now that`s enough spammed.
Hi Christof
I Think its because Hexfreds are hip at the moment in this Area .
Anyway I would like to try these ones. Please send me a mail about the cost of 12 Pieces whith Porto. Same Konto as The Boards ? I transfer the money when I got your mail.
Regards Bernhard
PS: Der Plan is: Teile sammeln bis ich die Amps bauen muß
I Think its because Hexfreds are hip at the moment in this Area .
Anyway I would like to try these ones. Please send me a mail about the cost of 12 Pieces whith Porto. Same Konto as The Boards ? I transfer the money when I got your mail.
Regards Bernhard
PS: Der Plan is: Teile sammeln bis ich die Amps bauen muß
Hi Bernhard,
I wouldn`t say hip - this sounds too much about fashion.
Take a look what the experts have to say about this.
Looks like this is much more than just fashion or even hype:
http://www.diyaudio.com/forums/showthread.php?postid=146277#post146277
http://www.diyaudio.com/forums/showthread.php?s=&threadid=28605
http://www.diyaudio.com/forums/showthread.php?s=&threadid=12162&highlight=
http://www.diyaudio.com/forums/showthread.php?s=&threadid=8683
http://www.diyaudio.com/forums/showthread.php?s=&threadid=8826
You got email!
Clever strategyPS: Der Plan is: Teile sammeln bis ich die Amps bauen muß
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