Interesting that rear connections shelf area is angled, instead of the usual front control area. This would be advantageous when connecting/disconnecting-My chassis design , for one of my tube amplifiers, and final work .
Novel idea-
Jim
I know, but driving the B+ converter hard takes 8 amps, plus some heater power and you will be in the 10A region. I had the fan anyway.You won't need the fan. It looks like you got the parts off of my shelf!
That 12V 13A supply is excellent. I routinely draw 5A from one in a 70°C enclosure - no ventilation. No failures in the years I've used them yet, not even the cheap filter caps.
I ran the thing loaded at 100W on B+ today, and without the fan you can fry eggs on the 12V rectifier heatsink, and the B+ converter drivers get very hot. Peace of mind 😀
P. S Yes, I stole your ideas 😁
Ah. Didn't realize you were running it that hard I like the fact it will start into a load like cold heaters instead of crying like a baby lol
The double fuse is a nice touch - there's already a fuse on the DC2416
Which MOSFETs is it using? If/when they blow, you can replace then with better ones
The older ones I had used 3205 (but generic, not IRF) but the newer ones are using some CS80N80A...
How hot was the coil on the boost converter? I've had at least one get much hotter than the heatsinks.
The double fuse is a nice touch - there's already a fuse on the DC2416
Which MOSFETs is it using? If/when they blow, you can replace then with better ones
The older ones I had used 3205 (but generic, not IRF) but the newer ones are using some CS80N80A...
How hot was the coil on the boost converter? I've had at least one get much hotter than the heatsinks.
The inverter uses YPI7575c. I will buy some more inverters, now that I see that it works properly. I would replace the heatsinks with taller ones, it comes with 25x15x10. The transformer seemed fine, I could hold a finger on it.Ah. Didn't realize you were running it that hard I like the fact it will start into a load like cold heaters instead of crying like a baby lol
The double fuse is a nice touch - there's already a fuse on the DC2416
Which MOSFETs is it using? If/when they blow, you can replace then with better ones
The older ones I had used 3205 (but generic, not IRF) but the newer ones are using some CS80N80A...
How hot was the coil on the boost converter? I've had at least one get much hotter than the heatsinks.
On the 12V SMPS, the rectifier diodes could probably be replaced with lower dropout voltage ones, because it's heatsink is the one that get's really hot without a fan.
Nice. Which module is the inverter providing up to 560V @ 200mA?I made a little bench for prototyping. Nothing special, but I like it
Voltages (all DC)
B+ up to 560V, 200mA
The inverter is from Aliexpress, bought it after noticing that @kodabmx used it in one of his amps:Nice. Which module is the inverter providing up to 560V @ 200mA?
https://www.aliexpress.com/item/326...-1;8.55;-1;-1@salePrice;GBP;search-mainSearch
Looks like this:
I can only vouch that this one works. I previously ordered a slightly different one, had silver heatsinks and no rectified output, and it died after 15 min of being lightly loaded. This one works quite well, gives a square rectified or AC outputs, 110/200/220/280, I used it with a doubler, just two 22uf caps connected to the output and the middle to one of the AC taps.
I measured again to be sure, and is around 525V @220mA, 560V @90mA.
As is the case with many boards from Aliexpress, your mileage may vary. I have tested the combination for around 3 hours, loaded at 220mA, so far so good. Difficult to get a better value for £8.55 inc delivery. I paid ~£130 for a Hammond 372JX a while ago. The whole setup here, including the 12V 150W SMPS is less than £20.
You might get less sag with bigger doubling caps... 47µF or 100µF but the coil will run hotter. I usually use the AC output and my own HER208 diodes BTW... Not sure it makes any difference.
Meanwhile, here's a shot of "When the socket needs to be replaced but you want to listen to music NOW!"
Meanwhile, here's a shot of "When the socket needs to be replaced but you want to listen to music NOW!"
Attachments
Some of the tube amplifiers built in recent years.
Regards,
Alex mm
Regards,
Alex mm
Attachments
Very nice craftsmanship Alex mm... What do you do with these after completion? Sell or collect?Some of the tube amplifiers built in recent years.
Regards,
Alex mm
Jim
How did you cut such clean holes in perboard for the sockets? Punches ?I made a little bench for prototyping. Nothing special, but I like it
Voltages (all DC)
B+ up to 560V, 200mA
12V 13A (powers the B+ inverter and 6.3V regulator.)
6.3V 2.5A max.
Big silent fan to be able to drive the B+ inverter at 100W
View attachment 1043479
View attachment 1043478 View attachment 1043480 View attachment 1043481
Clarke step drill bits. I first damaged one board using cheap ones from Amazon. You need sharp ones.How did you cut such clean holes in perboard for the sockets? Punches ?
Attachments
I just finished assembling this prototype last night. JPS64 and I have been working on this for some time now. It’s Bob Carver’s signature all valve preamp design executed in modern style with MCU control and mostly SMT technology and CNC chassis. Still linear supplies for the audio though.
In my case is not just the money, but also the skills. Was never good at it. Functional stuff, yes. Fine looking? Not so much.Nice looking man.
I wish I had the money to custom a chassis like that, alas I'm relegated to using Hammond boxes and hand tools.
Thanks. I have a lot of help from a talented team to develop something like this. Plus access to an incredible CNC house.Nice looking man.
I wish I had the money to custom a chassis like that, alas I'm relegated to using Hammond boxes and hand tools.
The inverter is from Aliexpress, bought it after noticing that @kodabmx used it in one of his amps:
https://www.aliexpress.com/item/32688618917.html?spm=a2g0o.productlist.0.0.1d364a12fPnUpq&algo_pvid=ebf3e158-aea8-4bce-94a8-40a4366f7f54&algo_exp_id=ebf3e158-aea8-4bce-94a8-40a4366f7f54-0&pdp_ext_f={"sku_id":"60468402583"}&pdp_pi=-1;8.55;-1;-1@salePrice;GBP;search-mainSearch
Looks like this:
View attachment 1043696
I can only vouch that this one works. I previously ordered a slightly different one, had silver heatsinks and no rectified output, and it died after 15 min of being lightly loaded. This one works quite well, gives a square rectified or AC outputs, 110/200/220/280, I used it with a doubler, just two 22uf caps connected to the output and the middle to one of the AC taps.
I measured again to be sure, and is around 525V @220mA, 560V @90mA.
As is the case with many boards from Aliexpress, your mileage may vary. I have tested the combination for around 3 hours, loaded at 220mA, so far so good. Difficult to get a better value for £8.55 inc delivery. I paid ~£130 for a Hammond 372JX a while ago. The whole setup here, including the 12V 150W SMPS is less than £20.
I might get myself a couple of these for bench testing given their flexibility.
Current project - late 1950s phillips receiver + record deck.
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