Found other parts. I may be able to sell the needed J107 & BF5102 for 30 kits of Calvin Buffer. You just have to buy the KSA1381, still in stock from Mouser, or I can buy them and sell you the complete semiconductor kits for the PCB 
So it is looking good for a run of Calvin buffer pcb...
SB
So it is looking good for a run of Calvin buffer pcb...SB
Better BOM?
Is anyone else having difficulty with the 2012 BOM supplied, or is it just me? It took me 2 hours just to figure out the common mode chokes, without paying 28euro shipping for the ones suggetsed. I'm still not sure what transformers to use, none listed. The leds just say 24 what voltage drop???
Does anyone have a BOM with mouser or Digikey part numbers as a starting point, it would make this process much faster There are far too many rabbit holes to go down associated with this build.
In other news the PCBS are VERY NCE!
Is anyone else having difficulty with the 2012 BOM supplied, or is it just me? It took me 2 hours just to figure out the common mode chokes, without paying 28euro shipping for the ones suggetsed. I'm still not sure what transformers to use, none listed. The leds just say 24 what voltage drop???
Does anyone have a BOM with mouser or Digikey part numbers as a starting point, it would make this process much faster There are far too many rabbit holes to go down associated with this build.
In other news the PCBS are VERY NCE!
Better BOM
Did you get the Paradise_Doc_Ver2020 from SB when you purchased your boards?
If you did look for file Paradise_Parts-List_2020_small.xlsx it is a very detailed BOM with part numbers for Mouser, Digikey and Newark with alternatives. As far as the X-formers go look back through this thread, there are alternatives given.
Double and triple check everything! There are a few minor errors such as some of the listed variable pots parts numbers on the list are side adjust and I believe they should be top adjust. If you don't check the data sheet you would not know as most of the mouser pic.'s show the same pot.
The documentation file is very comprehensive and detailed, some of the best I've seen.
Did you get the Paradise_Doc_Ver2020 from SB when you purchased your boards?
If you did look for file Paradise_Parts-List_2020_small.xlsx it is a very detailed BOM with part numbers for Mouser, Digikey and Newark with alternatives. As far as the X-formers go look back through this thread, there are alternatives given.
Double and triple check everything! There are a few minor errors such as some of the listed variable pots parts numbers on the list are side adjust and I believe they should be top adjust. If you don't check the data sheet you would not know as most of the mouser pic.'s show the same pot.
The documentation file is very comprehensive and detailed, some of the best I've seen.
I'm up for a set ofFound other parts. I may be able to sell the needed J107 & BF5102 for 30 kits of Calvin Buffer. You just have to buy the KSA1381, still in stock from Mouser, or I can buy them and sell you the complete semiconductor kits for the PCB
SB
Kelvin boards with matched transistors (but not without as I have no way of sourcing or testing them) . Please add me to the list?
I think we need a price!Found other parts. I may be able to sell the needed J107 & BF5102 for 30 kits of Calvin Buffer. You just have to buy the KSA1381, still in stock from Mouser, or I can buy them and sell you the complete semiconductor kits for the PCB
SB
Looks promising though
Thank You Mazzer! Of course the one file that wouldn't open, because I very recently changed my motherboard on this computer and havent re-entered my MS Office key to reactivate it. Guess I'll go looking for that key!
Jeffrey
Thank you but no need. I was able to reload office and now do have a very detailed BOM!
Jeffrey
Be careful with some of the BOM entries! A few notes to consider:
For the transformers the following is correct;
I used the Amgis because the Talema was out of stock (Digikey). They work just fine, no noise and they run barely warm and plenty of voltage available for regulators, even with Calvin.
Also the BOM doesn't list the 2R2 resistors needed for the pre-reg boards and the square Panasonic safety caps listed will NOT fit.
I could only find the shunt reg heat sinks at Newark UK. Those in US can still order.
As Algar_emi said early on it's not a simple (or cheap) project but the outcome is well worth the extra work!
I have to head out for a social thing but I will get together an updated list/BOM of what I used and post it here as soon as I can.
TJ
For the transformers the following is correct;
I used the Amgis because the Talema was out of stock (Digikey). They work just fine, no noise and they run barely warm and plenty of voltage available for regulators, even with Calvin.
Also the BOM doesn't list the 2R2 resistors needed for the pre-reg boards and the square Panasonic safety caps listed will NOT fit.
I could only find the shunt reg heat sinks at Newark UK. Those in US can still order.
As Algar_emi said early on it's not a simple (or cheap) project but the outcome is well worth the extra work!
I have to head out for a social thing but I will get together an updated list/BOM of what I used and post it here as soon as I can.
TJ
Hi. Sorry for the errors in the BOM, I tried my best but sometime errors are left in, it is a complex project and that I did a long time ago. I was my own beta tester but you know how it is, if a part doesn't fit you get the correct one, forget to update the BOM, and years later you forgot all about it... That's DIY for you I'm afraid.
Just to let you know that Simon (sq225917) completed his built and it is working fine, so the pcb has no error. There was a some problem at first but it was caused by some defective transistors. And thanks Simon for the info on the reject rate for the Calvin JFET matching. Seems like I can probably do only 5-10 sets then...
For those that plan to use the Calvin buffer also take note that you need to do some adjustements on the shunt regulators in order to match the higher supply consumption. It is well explained in the project documentation, but just to keep in mind if you want to try it. The docs said:
''For the shunt to function it needs to consume a few mA’s (30mA is the design value, actual values from 25 up to 50mA are acceptable). This results in 30ma x 18V = 540mW and 110mA x 8V = 880mW constant power consumption in the voltage regulator (Shunt, CVS and CCS), the total power supply consumption is: 2 x ((30mA 18V) + (110mA 8V (26Vin – 18Vout))) = 2.8Watt
When connecting the Calvin buffer an additional 30mA needs to be supplied, the CCS setting needs to be changed from 110mA to 140mA, this can be done by changing the 10 Ohm resistors to 7.5 Ohm resistors. The ‘normal’ power supply dissipation now changes to: 2 x ((30mA 18V) + (140mA 8V (26Vin – 18Vout))) = 3.4Watt
This should not be a problem with the supplied heat sink, but care should be taken to ventilate the area surrounding the PSU heat sink.''
If you get the Calvin you'll also get the full doc related to it as well...
Thanks
SB
Just to let you know that Simon (sq225917) completed his built and it is working fine, so the pcb has no error. There was a some problem at first but it was caused by some defective transistors. And thanks Simon for the info on the reject rate for the Calvin JFET matching. Seems like I can probably do only 5-10 sets then...
For those that plan to use the Calvin buffer also take note that you need to do some adjustements on the shunt regulators in order to match the higher supply consumption. It is well explained in the project documentation, but just to keep in mind if you want to try it. The docs said:
''For the shunt to function it needs to consume a few mA’s (30mA is the design value, actual values from 25 up to 50mA are acceptable). This results in 30ma x 18V = 540mW and 110mA x 8V = 880mW constant power consumption in the voltage regulator (Shunt, CVS and CCS), the total power supply consumption is: 2 x ((30mA 18V) + (110mA 8V (26Vin – 18Vout))) = 2.8Watt
When connecting the Calvin buffer an additional 30mA needs to be supplied, the CCS setting needs to be changed from 110mA to 140mA, this can be done by changing the 10 Ohm resistors to 7.5 Ohm resistors. The ‘normal’ power supply dissipation now changes to: 2 x ((30mA 18V) + (140mA 8V (26Vin – 18Vout))) = 3.4Watt
This should not be a problem with the supplied heat sink, but care should be taken to ventilate the area surrounding the PSU heat sink.''
If you get the Calvin you'll also get the full doc related to it as well...
Thanks
SB
Last edited:
Also take note that because of the Corona virus (yes I know that again...) the PCB Fab asked not to mix pcb color on the same order. Since I'll order only a small batch of Calvin buffer with some others pcb, all green solder mask, the Calvin will be green, not red as the rest. It is not making sense to order such small pcb just in one separate order...
Thanks for your understanding
SB
Thanks for your understanding
SB
Not a problem here.
Yes, this is DIYAudio not KITAudio. All component choices are up to the builder.
Some of the kits out there could learn a thing or two from the great documentation that has been done on this project.
Red and green boards.....could be early Christmas.
Thanks for the heads up.
I just got my Mouser order today and the Wima caps on SB's 2020 BOM do fit the pre reg board ( Mouser P/N 505-MKS2.1/63/5 ).
The 2R2 resistors do seem to be missing from the BOM. Does anyone know the wattage rating of the 2R2's?
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.