Cool! If I don't need it then perfect! Time saved on finding the best fit enclosure and worrying about fit or fixture but I think it'll probably work within my size constraints if I do need it. I understand that heat dissipation might be the more important thing to worry about with mu-metal shielding present.
Also, does any of these appeal to you or raise red flags (e.g. dimension)?...
1.2Ohm 1W: PR01000101208JA100 Vishay BC Components | Resistors | DigiKey
1.2Ohm 2W: PR02000201208JA100 Vishay BC Components | Resistors | DigiKey
1.2Ohm 3W: RWM04101R20JR15E1 Vishay Sfernice | Resistors | DigiKey
AC03000001208JAC00 Vishay BC Components | Resistors | DigiKey
(the 3W seem to have better temperature drift... Of the two the first advertises long-term stability so maybe that's the way to go)
2.4Ohm 1W: PR01000102408JR500 Vishay BC Components | Resistors | DigiKey
2.4Ohm 1W slightly lower temp drift: https://www.digikey.com/product-det...ronics-inc/RSF1JT2R40/RSF1JT2R40CT-ND/6594492
2.4Ohm 2W: https://www.digikey.com/product-det...ents/PR02000202408JR500/PPC2.4W-2CT-ND/597373
2.4Ohm 3W Vishay is out of stock on Digikey
2.2Ohm 2W much lower drift: https://www.digikey.com/product-detail/en/vishay-sfernice/RWM04102R20JR15E1/RWMA-2.2CT-ND/1587893
Thanks again!!
Last edited:
Maybe 2.7Ohm is better than 2.2Ohm since we're targeting 220mA+ but not too much?
Here's a low drift one (3W): RWM04102R70JR15E1 Vishay Sfernice | Resistors | DigiKey
Of course, lower power rated ones are more accurate: MBB02070C2408FCT00 Vishay BC Components | Resistors | DigiKey
Probably of negligible importance, though the large temperature drifts in standard Vishay is somewhat concerning... Any opinions...?
Here's a low drift one (3W): RWM04102R70JR15E1 Vishay Sfernice | Resistors | DigiKey
Of course, lower power rated ones are more accurate: MBB02070C2408FCT00 Vishay BC Components | Resistors | DigiKey
Probably of negligible importance, though the large temperature drifts in standard Vishay is somewhat concerning... Any opinions...?
Digikey resistor catalog = disappointment
Here are picks from Mouser:
2.4Ohm 1W 50ppm: RS01A2R400FE12 Vishay / Dale | Mouser
1.2Ohm 3W 50ppm: RS02B1R200FE12 Vishay / Dale | Mouser
There should be plenty of safety margin with these right?..
Here are picks from Mouser:
2.4Ohm 1W 50ppm: RS01A2R400FE12 Vishay / Dale | Mouser
1.2Ohm 3W 50ppm: RS02B1R200FE12 Vishay / Dale | Mouser
There should be plenty of safety margin with these right?..
Maybe the Vishay/Sfernice wirewound enamelled ones which have low enough ppm. Those resistors I remember inside Jadis gear because Sfernice was an old independent French components maker originally.
Those last two 50ppm Dales in Mouser look good also. But 1W will get hotter than 3W and it will look more different in size. 1W is still technically safe in your case.
Those last two 50ppm Dales in Mouser look good also. But 1W will get hotter than 3W and it will look more different in size. 1W is still technically safe in your case.
That's super interesting! Not doing this on a regular basis, I was initially confused whether Vishay sfernice is actually the common vishay or some less trustworthy company (though really resistors are resistors...). It seems like Vishay has acquired many others in the business and also has many product lines. It's also interesting that I was almost going to go for Taobao because I just couldn't believe that there's no low ppm 2.4ohm resisters out on the market, and I was more or less right. Tons of cheap resistors on Taobao ($1 top, usually much less) marked as 25ppm or even less in some cases. I would believe that most are probably legit too.
I couldn't find 2W for 2.4ohm even on Mouser I think, so I just went for the 1W, which hopefully should be enough since the CC is 0.08*2+0.10A. Square that and multiply into 2.4Ohm seems safe, but maybe it'll get hotter than need be... Also ordered dummy load resistors 25Ohm(5W) and 100Ohm(3W). Will post back when I get to assembling everything next month. Too much busy work but a lot of DIY fun!
)
Wow! Well, DIY is not really 'DIY' anymore when you use parts and designs from all over the world, not to mention the ideas shared on this global community! It's quite amazing, and makes for a good hobby.I'll definitely post back in a few weeks when I get some more time. Really looking forward to an upgraded dam1021 setup!
My project to build the Soekris DAM 1121 + Raspberry Pi + Tube-I-zator buffer stage starts today. Based on the chassis which I got, it is going to be very tight placement for all the boards. Bummer.
Option #1
House everything within the chassis. Still missing is the linear supply for the Pi. Will have to stack the Raspberry Pi on top of the Soekris DAM board. The MOSFET of the middle +ve UBiB will have to be air cooled instead of chassis sink.
Option #2
Have another chassis just for the PSU. Which means I will have to stack the 2 chassis on each other.
Feedback on pros and cons much appreciated. TIA.
Option #1
House everything within the chassis. Still missing is the linear supply for the Pi. Will have to stack the Raspberry Pi on top of the Soekris DAM board. The MOSFET of the middle +ve UBiB will have to be air cooled instead of chassis sink.
Option #2
Have another chassis just for the PSU. Which means I will have to stack the 2 chassis on each other.
Feedback on pros and cons much appreciated. TIA.
Have you consider to stack the toroids to save space?
If your case height permits of course.
If your case height permits of course.
Can also position Ubibs along their sides with M1 M2 holding them down as they sink to the chassis floor. There is provision for a screwdriver not to be blocked by parts when reaching to the Mosfets. Choosing low profile electrolytics also, so the regs can bunch closer together. Like Epcos C1 and Panasonic FM C2 C3.
@vgeorge, that's a brilliant idea, I tried but there isnt sufficient clearance. :-(
I've upgrated the FSP with Ultrabib 1.3 and now it's another story.
Everything is much better, clarity, transparence, dinamic, soundstage and energy.
My FSP is balanced, yes I've two printed circuit everyone managing the + and - of the
cartridge output. The gain is 56dB with only one K369.
I desoldered the components of the original volt regs and piggybacked the new ones.
R1 is 5.6R for about 110mA of ccs current.
The sinks of M2 are 7C°/W and the temperature is not hot.
Thank you again Nick
Everything is much better, clarity, transparence, dinamic, soundstage and energy.
My FSP is balanced, yes I've two printed circuit everyone managing the + and - of the
cartridge output. The gain is 56dB with only one K369.
I desoldered the components of the original volt regs and piggybacked the new ones.
R1 is 5.6R for about 110mA of ccs current.
The sinks of M2 are 7C°/W and the temperature is not hot.
Thank you again Nick
