Oh! - Now I see.... never could figure out why the other one was always safe. 
You could have saved me a couple trips to the hardware store had I known. 
I can't find anything bigger than 5A in my little town so I get some 8s from Mouser next week.
Thanks
Edit: On a suggestion from Daniel W. I used an automotive type fuse in one build. Has anyone else tried and had success with something similar.
You could have saved me a couple trips to the hardware store had I known. I can't find anything bigger than 5A in my little town so I get some 8s from Mouser next week.
Thanks
Edit: On a suggestion from Daniel W. I used an automotive type fuse in one build. Has anyone else tried and had success with something similar.
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Crap. I see I accidentally posted my "review," post 1331, in the wrong thread. Can a mod move it to the ACA thread?
doneThe automotive fuses may be OK for the LV side of the transformer. I cannot recall seeing the voltage rating on any automotive fuse.
Do the manufacturers issue data for these that can be compared to regular mains fuses, eg fast (F), standard, slow (T).
But for the Mains side and for all HV, the fuse must be rated at least as great as the voltage that needs to be broken.
Here in the UK we must use 250V fuses. NEVER automotive !
Do the manufacturers issue data for these that can be compared to regular mains fuses, eg fast (F), standard, slow (T).
But for the Mains side and for all HV, the fuse must be rated at least as great as the voltage that needs to be broken.
Here in the UK we must use 250V fuses. NEVER automotive !
FLG, what did you end up doing here. I'm having the same problem trying to finalise my BOM.
I want to run 30V rails, so I was figuring I needed 35V caps, but then the standard rails are 25V and the caps were specced at 25V (which if they were seeing full rail voltage doesn't leave any room for mains fluctuations)... I had a think about it and they are not directly across the power supply so probably aren't seeing the full rail voltage (anyone got a BA3 front + outputs end spice model?) or have done measurements as to what voltage these caps are actually seeing?
I'd like to run silmic II's or nichicon KZ's for C1 C2 but there is no way with 25V (or 35V!!) Panasonic FM's are looking like a candidate (for 35V as they are 12.5mm) as are panasonic FK's (10mm in a 35V) I just checked with a couple of 12.5mm diameter caps I have and they fit snuggly but anything bigger than that will be a forced fit. I thought it interesting that the Bias board has room for an 18mm cap (and my 25V silmics are only 16mm). Since the bias board cap will not see anywhere near 25V I find it interesting it is so big... was there thinking that you could use a higher capacitance device there?
More than likely I'm chasing shadows, but I tend to obsess over component selections
Tony.
Well, that was a while ago, but, I think I have "brown ones" there that are touching. That would be the Silmic IIs? I'll actually have to check...
I do however have a stock of 2200u Rubycons which are real good E-caps and are the same mfg of the renowned "Black Gate" units.??? Have to check
I do however have a stock of 2200u Rubycons which are real good E-caps and are the same mfg of the renowned "Black Gate" units.??? Have to check
thanks flg. I have some 1000uF 25V silmic II's and whlst they could be made to "fit" they are off at an angle. and not flush with the board. Was womdering if you ended up going with a lower voltage rating on the caps than the 25V specified in the bom.
I'll probably go with panasonic FM or FR. I've used rubicons in the past for small caps (I think ZA or ZL), they make some super low esr caps! and yes they are the manufacturer who used to make black gates
Tony.
I'll probably go with panasonic FM or FR. I've used rubicons in the past for small caps (I think ZA or ZL), they make some super low esr caps! and yes they are the manufacturer who used to make black gates
Tony.
Thanks Andrew. Daniels suggestion was actually for speaker protection on the F5. I just went ahead and used them on the mains as an experiment. I'll stick with the glass type now that I've been informed.
I was able to find 6.3A (and 10A, no 8s) slo-blo at Radio Shack this morning and they have been holding in the BA-3 all day. Fingers crossed that I can stay "close rated" as you always recommend.
I was able to find 6.3A (and 10A, no 8s) slo-blo at Radio Shack this morning and they have been holding in the BA-3 all day. Fingers crossed that I can stay "close rated" as you always recommend.
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16V 470uF SilmicIIthanks flg. I have some 1000uF 25V silmic II's and whlst they could be made to "fit" they are off at an angle. and not flush with the board. Was womdering if you ended up going with a lower voltage rating on the caps than the 25V specified in the bom.
I'll probably go with panasonic FM or FR. I've used rubicons in the past for small caps (I think ZA or ZL), they make some super low esr caps! and yes they are the manufacturer who used to make black gates
Tony.
I know we had this discussion some time back about thermal drift and dc offset on the BA-3 front end. I was measuring it the other day and it was flickering about certainly not steady. The mosfet heatsinks are the same style as with Nelson's photo but with six fins rated at 6.4c/w. Has anyone found that a bigger heatsink or even one that links the two mosfets works any better at controlling the dc offset or do we just live with it?
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To be honest, I have been running the amp without those heatsinks in the burn-in phase. I did check yesterday and I could hold on to them comfortably after hours of play - surprised me.
My plan is to do the same DIY fabrication as used on the F5 PS. It is made with 0.70 mm copper plate (4" X 10" @ $7) from the local hobby/craft store. Once I decide which cap will be used I can make the HS any shape and size needed.
My plan is to do the same DIY fabrication as used on the F5 PS. It is made with 0.70 mm copper plate (4" X 10" @ $7) from the local hobby/craft store. Once I decide which cap will be used I can make the HS any shape and size needed.
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