Algar_emi; Don't get me wrong, I'm super appreciative of all that you've done. Major cudos! I'm just trying to help and give back in some small way. Mine are complete and working also. They sound like...well...Paradise. 
Just stuffing them into chassis now. I hope you decide to go ahead with the Calvin boards. I'm in for sure!
mazzer; 1/4 watt is fine for the 2R2 they're just part of the rectifier snubbers.
The caps I had issue with were C15-C22. If you search for P10730-ND (Mouser and Digikey) it brings up ECQ-U2A104ML black plastic Panasonic safety caps, for some reason. They have matching specs except the board is 12.5mm lead spacing and the Panasonics are 15mm. I double checked everything except the spacing on the board so partly my own fault. Just wanted to save someone else from the same mistake. I ended up using Nichicon QXP2E104KRPT.
TJ
Just stuffing them into chassis now. I hope you decide to go ahead with the Calvin boards. I'm in for sure!mazzer; 1/4 watt is fine for the 2R2 they're just part of the rectifier snubbers.
The caps I had issue with were C15-C22. If you search for P10730-ND (Mouser and Digikey) it brings up ECQ-U2A104ML black plastic Panasonic safety caps, for some reason. They have matching specs except the board is 12.5mm lead spacing and the Panasonics are 15mm. I double checked everything except the spacing on the board so partly my own fault. Just wanted to save someone else from the same mistake. I ended up using Nichicon QXP2E104KRPT.
TJ
Algar_emi; Don't get me wrong, I'm super appreciative of all that you've done. Major cudos! I'm just trying to help and give back in some small way. Mine are complete and working also. They sound like...well...Paradise.
mazzer; 1/4 watt is fine for the 2R2 they're just part of the rectifier snubbers.
The caps I had issue with were C15-C22. If you search for P10730-ND (Mouser and Digikey) it brings up ECQ-U2A104ML black plastic Panasonic safety caps, for some reason. They have matching specs except the board is 12.5mm lead spacing and the Panasonics are 15mm. I double checked everything except the spacing on the board so partly my own fault. Just wanted to save someone else from the same mistake. I ended up using Nichicon QXP2E104KRPT.
TJ
Thank you TJ.
Do you have values for R9,10 on the RC filter board? I think they are also missing from the BOM.
I have not done extensive research on this project and probably won't build it right away as I have other projects going. I'm just trying to gather the parts while my head is in it and before some of the parts disappear from the major suppliers.
BTW if anyone is looking for the BC327 on Mouser you might notice that they have hfe designations for some of the parts beyond the normal selection grade. For example, P/N 512-BC32725BU
shows an hfe of 400 in the description. Great!, right? Not so much... I measured a handful and they seem to be in the 300 range. Mouser is looking into it for me so we will see... just a warning. If anyone has suggestions for manufacturers or suppliers that supplied the BC327's in the hfe 400-450 I would be grateful.
R9 & R10 on the filter board are just limiting resistors for LEDs, not critical. I used 2.2K. The BC327/337's should be BC327-40 & BC337-40. Mouser # 512-BC33740TA and 512-BC32740TA. Find best matches (PNP/NPN) in the highest 400's or as close as you can. Depends a lot on what you measure them with so just try for that. Mine were all low 400's and works just fine.
TJ
TJ
Thanks takitaj for filling in the mssing info in the BOM. Indeed I don't usually put led indicator resistor values, often called them RLED because the actual value often depends on what intensity the builder wants (even truer for the front panel led). I usually try different values myself and settle on the one value that gives the best result for me.
My fault, 2k2 is just fine indeed.
My fault, 2k2 is just fine indeed.
Calvin Buffer PCB and matched transistor sets
Received the last batch of Paradise PCB set, already sold two extra to Simon. I have a few left and they will be probably the last batch before a long time, major kitchen renovation project coming my way in the next few months...
I'm planning to order a small batch of Calvin buffer pcb. Price will be 20U$ for a stereo set, and yes I can now order them in RED
Still haven't figure out how much to charge for the Calvin buffer matched transistor sets. Simon said that the reject rate is quite high, so I may ended up having to charge the parts total cost, divided by the few sets I'll be able to match.
Anyway it will be probably your last chance to get these parts, since the BF502 JFET was discontinued long ago. Just to give you an idea I had to order 50 extra J107 and they cost now 0.71U$ each.
Already 4 sets are reserved, so let me know if your are interested, first in, first served...
Thanks
SB
Received the last batch of Paradise PCB set, already sold two extra to Simon. I have a few left and they will be probably the last batch before a long time, major kitchen renovation project coming my way in the next few months...
I'm planning to order a small batch of Calvin buffer pcb. Price will be 20U$ for a stereo set, and yes I can now order them in RED
Still haven't figure out how much to charge for the Calvin buffer matched transistor sets. Simon said that the reject rate is quite high, so I may ended up having to charge the parts total cost, divided by the few sets I'll be able to match.
Anyway it will be probably your last chance to get these parts, since the BF502 JFET was discontinued long ago. Just to give you an idea I had to order 50 extra J107 and they cost now 0.71U$ each.
Already 4 sets are reserved, so let me know if your are interested, first in, first served...
Thanks
SB
I ordered a batch of 400 327 and 337 from mouser last week, the grouping for hfe is the best I've ever had from a single purchase. Over 70% of both types fell in a range of 405hfe +/- 10. So 200 of each will give you enough for a 1% match across the board.
For lowest offset match the input stage on both boards as one group, match the input stage current mirror as another group and the riaa current mirrors as a group also.
I'll add the parts number later tonight
For lowest offset match the input stage on both boards as one group, match the input stage current mirror as another group and the riaa current mirrors as a group also.
I'll add the parts number later tonight
I'm in for the Calvin boards only...Received the last batch of Paradise PCB set, already sold two extra to Simon. I have a few left and they will be probably the last batch before a long time, major kitchen renovation project coming my way in the next few months...
I'm planning to order a small batch of Calvin buffer pcb. Price will be 20U$ for a stereo set, and yes I can now order them in RED
Still haven't figure out how much to charge for the Calvin buffer matched transistor sets. Simon said that the reject rate is quite high, so I may ended up having to charge the parts total cost, divided by the few sets I'll be able to match.
Anyway it will be probably your last chance to get these parts, since the BF502 JFET was discontinued long ago. Just to give you an idea I had to order 50 extra J107 and they cost now 0.71U$ each.
Already 4 sets are reserved, so let me know if your are interested, first in, first served...
Thanks
SB
Ta
327 and 337 transistors.
Transistors tend to have hfe spread across a wide curve, it's not unusual to have a spread of hfe across about 80 in a single batch of transistors, and usually the 337 are 10-20 higher across the board than the 327.
The last two batches of ammo tape parts I had from Mouser all fell within a very narrow range of 405 +/-10 and the 337 were only about +5 when compared to the 327, so given the distribution curve there's a huge overlap and matching was easy.
Obviously it'll change as the parts come from different locations on the wafer, or as production varies day to day but at the minute, they're great.
512-BC33740TA and 512- BC32740TA,
The Diotec and National parts that i sampled at the same time were crap 327 and 337 were out by 50 which makes matching them all but impossible.
Have fun 200 of each should be more than enough.
Transistors tend to have hfe spread across a wide curve, it's not unusual to have a spread of hfe across about 80 in a single batch of transistors, and usually the 337 are 10-20 higher across the board than the 327.
The last two batches of ammo tape parts I had from Mouser all fell within a very narrow range of 405 +/-10 and the 337 were only about +5 when compared to the 327, so given the distribution curve there's a huge overlap and matching was easy.
Obviously it'll change as the parts come from different locations on the wafer, or as production varies day to day but at the minute, they're great.
512-BC33740TA and 512- BC32740TA,
The Diotec and National parts that i sampled at the same time were crap 327 and 337 were out by 50 which makes matching them all but impossible.
Have fun 200 of each should be more than enough.
Thanks for the info.
My first order from Mouser of 512-BC33740BU and 512-BC32740BU did not match well at all. BC337's hfe is clustered around 450 and BC327's hfe clustered around 380 so I had no overlap with 200 parts of each. I just ordered 200 each of 512-BC33740TA and 512-BC32740TA and hoping for better luck.
BC337 / BC327 Matching update
After getting conflicting hfe readings from a multimeter hfe tester and a cheapo transistor tester I built up the Hesener's test circuit shown on pg.7 post #67 of the Paradise Builders Thread.
Using Hesener's circuit the difference between the BC32740BU's and BC33740BU's decreased considerably. I ended up with a good number of parts overlapping around hfe of 420 or so. I'm not sure which method of measuring is best but I tend to trust Hesener's method as more parameters are controlled. So it does seem that 200 of each would be enough to get some usable matches.
After getting conflicting hfe readings from a multimeter hfe tester and a cheapo transistor tester I built up the Hesener's test circuit shown on pg.7 post #67 of the Paradise Builders Thread.
Using Hesener's circuit the difference between the BC32740BU's and BC33740BU's decreased considerably. I ended up with a good number of parts overlapping around hfe of 420 or so. I'm not sure which method of measuring is best but I tend to trust Hesener's method as more parameters are controlled. So it does seem that 200 of each would be enough to get some usable matches.
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