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[B]PRP resistor group buy for the EUVL F5X build[/B]

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#43
What are in the bag?

Before I forget, I better describe what are in the bags 😉

For those who purchase 2 sets:
- there is one large bag for each person, the person's diyaudio id is on it.
- inside the large bag, there are a few smaller bags:
* One is labeled Assorted which contains 4 matched 220R's, 20 x 1K,
8 x 47R, 8 x 1.5K, 4 x 100K, 2 x 10R. Same values are wrapped together.
* 3 bags labeled 33.X, each bag contains one set of 8 matched 33R
resisters. You will be using 1 from each bag and parallel 3 of
them for each 11R location in the schematic.
* 4 bags labeled 220.X, each bag contains one set of 8 matched 220R
feedback resisters. You will be using 1 from each bag and parallel 4 of
them for each 55R location in the schematic.

For those who purchase 4 and 5 sets:
- there is 2 large bags for each person, the person's diyaudio id is on it.
- inside one large bag, there are a few smaller bags that contain the must
be matched resistors:
* 3 bags labeled 33.X, each bag contains one set of 16 or 20 matched 33R
resisters. You will be using 1 from each bag and parallel 3 of
them for each 11R location in the schematic.
* 4 bags labeled 220.X, each bag contains one set of 16 or 20 matched
220R feedback resisters. You will be using 1 from each bag and parallel 4
of them for each 55R location in the schematic.
Nic, your 220R's are in bag of 12 and bag of 8 as I was too lazy to rebag
them, but they are totally matched.
- inside the second large bag, there are:
* 1 assorted bag that contains 8 or 10 matched 220R's, 4 or 5 x 10R's,
8 or 10 x 100K's. Same types are wrapped except the 220's.
* 1 bag of 16 or 20 x 1.5K
* 1 bag of 16 or 20 x 47R
* 1 bag of 40 or 50 x 1K

DO NOT pay too much attention to the .X value. This is just the reading from my Fluke. I am pretty sure it is not 100% accurate 😉 All it matters is the same readings to designate as matched.

Thanks!!
 
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#44
For those who are in the PRP/Fuku GB AND are also in my other 2 GB's and are not in USA:
- 2SK3897/2SJ618, Keratherm Pads, see this spreadsheet.
- 2SK2013/2SJ313, see this spreadsheet.

You are qualified to ship these items along with the PRP and Fuku. I sent some PM's in the last few days to remind this option but didn't get all response. I am gong to finish up match the 2SK2013/2SJ313 this weekend and will calculate the total of your batch and request payment.

I can accommodate however you want to ship your items, but please let me know. I will great appreciate if you tell me your shipping preference (direct or with PRP/Fuku). Either spreadsheet has my email address next to my id. You can email me using that email address (my PM inbox is quite full).

Thanks!!
 
#48
> Just to double check is this quantity sufficient for a balanced F5X?

For each channel F5X, you need

4x Keratherm Red TO247-2 for the main amp
2x Keratherm Red TO247-2 for the regulator
8 X Keratherm Red TO220-4 for the rectifier diodes

If I am not totally forgetful (I am occasionally these days) that's all you need.


Patrick
 
#50
I think you meant :

12 X Keratherm Red TO247-2.
16 X Keratherm Red TO220-4.

And I would suggest you order 25% extra, as they are fragile.
You might have to replace them if you for some reason have to unscrew your devices from the heatsinks.
(i.e. only good for one time if you are unlucky)


Patrick
 
#51
From this post, it will be
12 x TO-247-2 and 22 x TO-220-4.
However, due to the way the TO-220-4 is packaged (7 pads in one strip), I have to force everyone to round up to a multiple of 7 because I don't want to cut into the middle of a strip. John, I rounded you up to 42 x TO-220-4 and added to the spreadsheet.

Thanks!!
 
#54
> It's 22 TO220 pads you'd need in total (six additional TO220 devices on protection board)

Yes, but I also said in the same post that the protection board TO220s are not critical at all and can easily live with mica & grease.

So essential 16x TO220.
Luxury 22x TO220.

🙂


Patrick
 
#56
Wow! I didn't see this group buy, 2SK2013/2SJ313, are these the output devices? I'm in the resistor GB. If possible I would like a set of outputs for a stereo amp. What are those 2SK3897/2SJ618's for ? I guess I'd need pads also. If I'm too late, thanks anyway.
 
#57
Let see I can answer Jan and ichiban at once 🙂

Juma used F5 as the basis and design the TF5 in this thread.
A few member built this circuit and had good feedback. In here, Juma used 3 x N-P pairs per channel. In post #42, the same circuit was tweaked a little to make it a line preamp!!

In Papa's new BA-3, he also used 2sk2013/2sj313 as the reference parts, see Papa's article here. Then later, Papa published the BBA-3 (Balanced BA-3) which is effectively 2 x BA-3 with minor tweak 🙂 The BA-3 boards are also available in the diyaudio store !!!

symslow of our F5X test team also used these in the UGS and had good result. Since I am quite intrigue of so many usage of these transistors, I bought some so that I can match them up and have some fun for future projects. Obviously, I need more than I use to have good matches 🙂 Hence, I have some excess to sell.

Ichiban,

The 2SK3897/2SJ618 are for the regulator, one set per one stereo F5X. I still have some Keratherm pads left, plenty of TO-220-4 but only have 20 TO-247-2 (you need 12 for a stereo F5X).

Thanks!!
 
#59
can i add some of those keratherms? i need 8 x to-274-2 and say another 28 x to220-4 (4 x 7) sorry i dropped off this was gonna get 50 but I've go so many parallel projects going at the moment i lost track of this one.
 
#60
qusp, I have plenty of TO-220-4 . I ordered 2000 from the factory, but I only have 20 TO-247-2 left which should be just enough for you (8) and Ichiban (12). If you 2 decide to go for it, let me know, and I will add you 2 to the spreadsheet.

Jan, I apologize that I didn't quite answer your question and might confuse you. The 2SK2013/2SJ313 are not for F5X at all. I just happen to have some available for other interesting projects as described above and can ship with the F5X parts.
 
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