Yah from RS - one hums quite badly up close, but they were relatively cheap 😛
500VA, 32V no load secondary ratings. Seemed made for the ABB.
For Aussies wanting toroidals it's either Talema from RS Components, Harbuch in NSW or Antek in North America and then there is PowerTran lol.
Any I miss?
And there is Element14:
https://au.element14.com/
Looks like Altronics has a few options too, no idea about the quality:
Transformers | Toroidal Mains - Altronics
https://au.element14.com/
Looks like Altronics has a few options too, no idea about the quality:
Transformers | Toroidal Mains - Altronics
FYI - I got a quote from Tortech to produce an appropriate toroidal transformer for ABB:
Item: 2x 500VA 240/30/30V Open Toroidal Transformer (500VA Transformer with Dual 30V Output Windings and ES.).
Total price for both units: $490 including GST, plus $35 freight. ($245 per unit including GST, plus freight).
Availability: 1-2 Weeks.
Unfortunately price was too high for this particular situation.
It's also worth considering SMPS (Meanwell from Mouser) as cost effective options for us Aussies depending on requirements (i.e. if no off the shelf toroidal is available).
Item: 2x 500VA 240/30/30V Open Toroidal Transformer (500VA Transformer with Dual 30V Output Windings and ES.).
Total price for both units: $490 including GST, plus $35 freight. ($245 per unit including GST, plus freight).
Availability: 1-2 Weeks.
Unfortunately price was too high for this particular situation.
It's also worth considering SMPS (Meanwell from Mouser) as cost effective options for us Aussies depending on requirements (i.e. if no off the shelf toroidal is available).
Try buying from the website and drop your 500VA for a regular 300VA with two 30VA secondaries.
HD
HD
Can we ask what trafo's you ended up getting?
Zman01 has some experience getting 500VA (?) Toroidy's shipped to AUS then hand-carried (I feel sorry for his friend's back lugging these around) to Dhaka - LOL 🙂
Zman01 has some experience getting 500VA (?) Toroidy's shipped to AUS then hand-carried (I feel sorry for his friend's back lugging these around) to Dhaka - LOL 🙂
Yah I got these as shown in the previous build photo: 0500P1-2-030K | 2 Output Toroidal Transformer, 500VA, 2 x 30V ac | RS Components
The RSPRO branded version of the same unit is: 2 Output Toroidal Transformer, 500VA, 2 x 30V ac | RS Components
There's also non-potted versions available at RS.
Quite affordable compared to other options in Australia 🙂
Here's an updated list of the usual suspects,
they're ordered by package and transconductance.
I've found some combinations with low rdson and matching transconductance:
TO-247 IXFH110N10P + IXTH90P10P
TO-247 IXFH74N20P + IXTH90P10P
TO-264 IXTK120N20P + IXTK170P10P
TO-264 IXTK102N30P/IXFK102N30P + IXTK170P10P
What would be a good combination for an Alpha4R 2A from the following candidates?
N-Channel
P-Channel
Regards,
Danny
they're ordered by package and transconductance.
I've found some combinations with low rdson and matching transconductance:
TO-247 IXFH110N10P + IXTH90P10P
TO-247 IXFH74N20P + IXTH90P10P
TO-264 IXTK120N20P + IXTK170P10P
TO-264 IXTK102N30P/IXFK102N30P + IXTK170P10P
What would be a good combination for an Alpha4R 2A from the following candidates?
N-Channel
Code:
[SIZE="3"]
Gfs Ciss Crss RdsOn Rthjc Rthcs C/W
Fairchild FQA28N15 TO3PN N 227W 33A 150V 20S 1250pF 50pF 90mOhm 0.66 0.24
Fairchild FQA32N20C TO3PN N 204W 32A 200V 20S 1700pF 185pF 82mOhm 0.61 0.24
Fairchild FDA69N25 TO3PN N 480W 69A 250V 25S 3570pF 84pF 41mOhm 0.26 0.24
Fairchild FQA40N25 TO3PN N 280W 40A 250V 29S 3100pF 70pF 70mOhm 0.45 0.24
Fairchild FQA46N15 TO3PN N 250W 50A 150V 36S 2500pF 100pF 42mOhm 0.60 0.24
Fairchild FQA70N15 TO3PN N 330W 70A 150V 48S 4150pF 135pF 28mOhm 0.45 0.24
Fairchild FQH90N15 TO3PN N 375W 90A 150V 68S 6700pF 200pF 18mOhm 0.40 0.24
IXYS IXTH64N10L2 TO247 N 357W 64A 100V 27S 3620pF 235pF 32mOhm 0.35 0.21
IXYS IXFH70N20Q3 TO247 N 690W 70A 200V 32S 3150pF 100pF 40mOhm 0.18 0.21
IXYS IXFH110N10P TO247 N 480W 110A 100V 40S 3550pF 440pF 15mOhm 0.31 0.21
IXYS IXFH74N20P TO247 N 480W 74A 200V 44S 3300pF 190pF 34mOhm 0.31 0.25
IXYS IXTH75N10L2 TO247 N 400W 75A 100V 44S 8100pF 350pF 21mOhm 0.31 0.21
IXYS IXTH80N20L TO247 N 520W 80A 200V 45S 6160pF 520pF 32mOhm 0.24 0.21
IXYS IXFH96N20P TO247 N 690W 96A 200V 52S 4800pF 270pF 24mOhm 0.25 0.21
IXYS IXTH96N20P TO247 N 600W 96A 200V 52S 4800pF 270pF 24mOhm 0.25 0.21
IXYS IXFH100N25P TO247 N 600W 100A 250V 56S 6300pF 240pF 27mOhm 0.25 0.21
IXYS IXFH120N15P TO247 N 600W 120A 150V 60S 4900pF 330pF 16mOhm 0.25 0.21
IXYS IXFH72N30X3 TO247 N 390W 72A 300V 60S 5400pF 2pF 15mOhm 0.32 0.25
IXYS IXFH80N25X3 TO247 N 390W 80A 250V 64S 5430pF 2pF 13mOhm 0.32 0.25
IXYS IXFH140N10P TO247 N 600W 140A 100V 65S 4700pF 600pF 11mOhm 0.25 0.21
IXYS IXFH94N30P3 TO247 N 1040W 94A 300V 68S 5510pF 25pF 36mOhm 0.12 0.25
IXYS IXFH140N20X3 TO247 N 480W 140A 200V 94S 7660pF 5pF 10mOhm 0.26 0.25
IXYS IXFK90N20Q TO264 N 500W 90A 200V 50S 6800pF 480pF 22mOhm 0.26 0.15
IXYS IXTK82N25P TO264 N 500W 82A 250V 52S 4800pF 210pF 38mOhm 0.25 0.15
IXYS IXTK102N30P TO264 N 700W 102A 300V 57S 7500pF 230pF 33mOhm 0.18 0.15
IXYS IXFK102N30P TO264 N 700W 102A 300V 57S 7500pF 230pF 33mOhm 0.18 0.15
IXYS IXTK88N30P TO264 N 600W 88A 300V 60S 6300pF 190pF 40mOhm 0.21 0.15
IXYS IXTK120N20P TO264 N 710W 120A 200V 63S 6000pF 265pF 22mOhm 0.21 0.15
IXYS IXFK140N20P TO264 N 830W 140A 200V 84S 7500pF 280pF 14mOhm 0.18 0.15
IXYS IXFK120N30P3 TO264 N 1130W 120A 300V 90S 8630pF 20pF 27mOhm 0.11 0.15
[/SIZE]P-Channel
Code:
[SIZE="3"]
Gfs Ciss Crss RdsOn Rthjc Rthcs C/W
Fairchild FQA36P15 TO3PN P 294W 36A 150V 19S 2550pF 110pF 90mOhm 0.51 0.24
IXYS IXTH52P10P TO247 P 300W 52A 100V 20S 2845pF 275pF 50mOhm 0.42 0.21
IXYS IXTH50P10 TO247 P 300W 50A 100V 22S 4350pF 733pF 55mOhm 0.42 0.25
IXYS IXTH48P20P TO247 P 462W 48A 200V 32S 5400pF 170pF 85mOhm 0.27 0.21
IXYS IXTH90P10P TO247 P 462W 90A 100V 37S 5800pF 510pF 25mOhm 0.27 0.21
IXYS IXTX170P10P TO247 P 890W 170A 100V 58S 12600pF 930pF 14mOhm 0.14 0.15
IXYS IXTK90P20P TO264 P 890W 90A 200V 51S 12000pF 250pF 44mOhm 0.14 0.15
IXYS IXTK170P10P TO264 P 890W 170A 100V 58S 12600pF 930pF 14mOhm 0.14 0.15 [/SIZE]Regards,
Danny
Hi Danny,
Thank you for your wonderful list of suspects! Seeing them still, not moving, makes it much easier to identity the crime choices.......
The 4R ALPHA needs >200W devices with lowish transconductance and max voltage.
The ones I like are FQA32N20C nmos and FQA36P15 pmos. These have less than Ciss of 2.6nF and will cope with the 50W dissipation with ease.
The big amp, the BB, needs much bigger mosfets. I like IXFH74N20P nmos + IXTH48P20P pmos because they are TO247 - good thermal capacity - and low Ciss for high dissipation and current.
Again, Danny, thank you!
Hugh
Thank you for your wonderful list of suspects! Seeing them still, not moving, makes it much easier to identity the crime choices.......
The 4R ALPHA needs >200W devices with lowish transconductance and max voltage.
The ones I like are FQA32N20C nmos and FQA36P15 pmos. These have less than Ciss of 2.6nF and will cope with the 50W dissipation with ease.
The big amp, the BB, needs much bigger mosfets. I like IXFH74N20P nmos + IXTH48P20P pmos because they are TO247 - good thermal capacity - and low Ciss for high dissipation and current.
Again, Danny, thank you!
Hugh
Hi Hugh,
Thanks for the recommendations!
Any reason why to select the IXTH48P20P above the IXTH90P10P ?
The IXTH90P10P has a much lower Rdson.
Regards,
Danny
Thanks for the recommendations!
Any reason why to select the IXTH48P20P above the IXTH90P10P ?
The IXTH90P10P has a much lower Rdson.
Regards,
Danny
She's alive!
Took much longer than necessary because I stupidly blew one channel and associated SLB by incorrectly swapping the output FETs! 🙁 Fortunately both boards were salvageable.
Sounds gorgeous 🙂 Thanks to all involved in its design.
Took much longer than necessary because I stupidly blew one channel and associated SLB by incorrectly swapping the output FETs! 🙁 Fortunately both boards were salvageable.
Sounds gorgeous 🙂 Thanks to all involved in its design.
Congrats Aive!!
Another Alpha BB is born 😀
What is the working voltage you ended up with?
aive,
Congratulations on getting the amp running. 🙂
You are playing it with the KEF LS50 (the black speaker with the copper color driver in the background)?
Congratulations on getting the amp running. 🙂
You are playing it with the KEF LS50 (the black speaker with the copper color driver in the background)?