:yes:
So My Quicksilver keeps blowing the fuse..
- Thread starter similost
- Start date
That's a good idea. :thmbsp: This thread has wandered around here and there.
Thanks! I've always loved painting and drawing but don't spend near enough time doing it as I would like - maybe I shouldn't hang around the computer as much!
Thanks Keg!
LoL, yeah, this internet & communication explosion sure just eats up time. I'll be back to the solder tomorrow. It's been a long work week and I'm too tired to concentrate tonight. :sigh:
LoL, yeah, this internet & communication explosion sure just eats up time. I'll be back to the solder tomorrow. It's been a long work week and I'm too tired to concentrate tonight. :sigh:
shawnra
Well-Known Member
a quick fix to check things out would be to take the first cap out of service so the power supply becomes a LC filter not CLC. This will drop the B+ by about 25% and should be quite safe to do. 300uf is huge to a tube rectifier and would certainly stress it right out.
When the inductor is the first component in the power supply filter it will provide better current regulation albeit at a cost to output voltage.
included is a good quick guide to supply voltages related to filter types
When the inductor is the first component in the power supply filter it will provide better current regulation albeit at a cost to output voltage.
included is a good quick guide to supply voltages related to filter types
similost
Rockin and Rollin....
So did anyone else hear that 747 that just flew right ofer the top of my head???
You totally lost me..
Kegger wanted me to add the CL-80's then swap out tubes then get him new voltage readings, then from there if everything was good I was going to recap everything using smaller values in the rectifiers.
You totally lost me..
Kegger wanted me to add the CL-80's then swap out tubes then get him new voltage readings, then from there if everything was good I was going to recap everything using smaller values in the rectifiers.
Kegger
R.I.P. 1/12/1966 - 6/1/2017
Everything else in the supply is setup as original? (caps an choke where they were)
And now with the CL-80's in place take an AC voltage measurement at the output
tube heaters, measure from pin 2 to pin 7, an give the exact reading you get, just
so you have the right scale it will be AC voltage and near/roughly 6.3v there.
(I want to see what the thermistors did to the power tranny output)
Also let the amp warmup up a bit to take final readings, so the thermistors "fade".
And now with the CL-80's in place take an AC voltage measurement at the output
tube heaters, measure from pin 2 to pin 7, an give the exact reading you get, just
so you have the right scale it will be AC voltage and near/roughly 6.3v there.
(I want to see what the thermistors did to the power tranny output)
Also let the amp warmup up a bit to take final readings, so the thermistors "fade".
Kegger
R.I.P. 1/12/1966 - 6/1/2017
Unfortunately that little choke won't take the abuse of "input" duty, we'd need a much beefier choke.
(what were gunna do is use a Much smaller input cap, Then go through the choke to the outputs)
shawnra
Well-Known Member
sorry I did not explain myself well enough, I used to teach a course at a private college on power supply design and covered this exact arrangement. an initial schematic that was posted outlined that this is a CLC supply filter or capacitor, inductor, capacitor filter. When a capacitor is the first filter device used to filter AC it will see the most reactance and therefor boost voltage, hence the transformers secondary voltage multiplied by 1.414 to get your B+. This is at a cost though, it will cause a large spike in current when it initially charges upon power up causing stress on the rectifier as well your current capability will be reduced. Your current multiplier in this arrangement is .62. The schematic outlines 300uf and this is huge to a 5au4 or the like. If you removed the first cap you would have an inductor first in the power supply filter and now this would see the most reactance therefor it changes the entire filter characteristics of the design. right off the bat your filter now becomes a LC filter and your secondary transformer voltage will now be multiplied by .90 but your current is increased from a factor of .62 to a factor of .94, considerably more current available albeit at a cost to your B+ which now would be about 30% less. Because the inductive loaded filter inherently regulates current it acts as a current limiting device upon power up which will limit the current inrush to charge the capacitor that sits after it in the filter design. This will aid in prolonging your rectifier life span and allow a gentle cycle to occur every time the unit is turned on. So this would allow you to trouble shoot if it is a mains filter cap and also allow a safer operating environment because your B+ would be a bit lower and the stress on your rectifier would lessen because the inrush of current is stayed.
bricktop
Couch woofer
That's true, when the first inductor is able to handle that duty. The one that's in there will likely saturate with no first cap, and it will probably vibrate like hell too. They need to be specially gapped to handle the AC voltage across it, which usually means they are rather large to have sufficient inductance.
shawnra
Well-Known Member
yes you are right the inductor would drop considerable more voltage because of it's increase reactance to the AC therefor needing to be properly rated. gotta love ohm's law Eh! I think that this little discussion really encapsulates all that has intrigued me about electronics and specifically capacitance and inductance over the years. The complete opposite properties and natures of these two fundamental reactances are what has enabled the World to go round for the last 100 years. we have based so much of our lives on these principles.
similost
Rockin and Rollin....
Pretty much everything on the schematic you changed, and the other caps in the amp..
I can still get what ever else is needed.. and if I don't use some of the parts no biggie.. I'll fnd somewhere else I can glue them in..
I did get the 330mf stuffed in one can, and the 33mf stuffed in the other. Haven't glued te 33mf cap back together though.. just the cap mounted to the base..
I can still get what ever else is needed.. and if I don't use some of the parts no biggie.. I'll fnd somewhere else I can glue them in..
I did get the 330mf stuffed in one can, and the 33mf stuffed in the other. Haven't glued te 33mf cap back together though.. just the cap mounted to the base..
