Then they will fit , facing down with the 7 devices bolted upside down along the bottom. The input edge of the board will be at the top. you will be left with 1/4 " at the top.
My reason for concern , I just may give you 2 PCB's(you be the guinea pig)
PS - you still could just recap the original
OS
Okay, now turning my hat around over to the "customer" side. . .
The PCB's is such a very nice offer and recapping is still possible, but I have to say no to both, because neither get the job done. I need the kit.
PCB's are the least of what is needed for someone who's unfamiliar with, and not good at, shopping for discrete parts. The names, brands, locations, all vary and every single one of these parts will have some datasheet with a different version that has totally different figures even if the name of the part is exactly the same. This cannot lead to achieving expected results.
Everyone is different and your skills are obviously greater than mine. I need the kit.
This is what you would hear from any customer. And you know that I have not yet located all of the exact parts for the Frugalamp board. Its collection is growing, but its all guesswork and failure is expected.
Oh, that's true.
But, I just thought it would save him a headache to hear it bluntly now from one person rather than a snowball effect later on.
And its entirely true that I do want an AX with exactly* the parts that OStripper would use. Exactly, meaning: Either buy the parts along with the board or use an on-line store's exact stock (SKU) numbers.
The thing is a high power amplifier--any parts variance will be amplified! Inserting a foreign object into a high power amplifier is a temporary novelty like sand in your vaseline and rather abrasive.
But, I just thought it would save him a headache to hear it bluntly now from one person rather than a snowball effect later on.
And its entirely true that I do want an AX with exactly* the parts that OStripper would use. Exactly, meaning: Either buy the parts along with the board or use an on-line store's exact stock (SKU) numbers.
The thing is a high power amplifier--any parts variance will be amplified! Inserting a foreign object into a high power amplifier is a temporary novelty like sand in your vaseline and rather abrasive.
Including Mouser ,digikey , farnell #'s is no problem. To include the parts would require shipping 2 times and a lot of cash $$ .
The parts required for the ax have some flexibility , any output pair with 80-100 Hfe/200V+ Vce (any TO-264 or TO-3P ON product , 2sc5200/a1943 , any sanken TO-3P) 2sc2240/a970 will work fine for IPS/CM , with a slight hit in performance , even mje340/350 can be used in the VAS. Vbe can be either the mje340 or 2sc3503.
Resistors can be 5 % radio shack specials except for the input pair degeneration. Capacitors can be any proven popular brand (Nichicon / panasonic, CDE) of sufficient derating. Not all parts are available everywhere.
PS - input caps and LPF , Cdom ARE specific ... 4.7uF/ 50 polyester (wima) for input , silver mica for Cdom and poly for any filters is minimum quality.
OS
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Include the parts means: "kit"
Although the price tag will be larger in the short term, the quality control, faster results, lack of confusion and easier technical support, stunningly overwhelms that price difference.
Off you go then, I'm sure if you invest the time, effort and money to set up a GB for the parts, OS will give you a suitable BOM.
Oh, no worries. I have a very fine parallel chip amp that has run flawlessly for years and continues to satisfy. So, there's no problem waiting on the availability of an excellent discrete amp kit, for as long as that might take. Until then, the chips will continue to substitute admirably.
BAD CAPS ... new ones ???
I received a gift of 20 marcon (united chem-con) 470u@100v caps. Never used them until now. Fired up the Nikko power supply (below 1) and got magic smoke and popped caps !!! You ARE right, Daniel , I must test every part I get... even new ones. These marcons were made in "china" DEFECTIVE JUNK even when new. In the first pix I put 2 panasonics in just to test and I got my 68v high voltage supply .... my sanwha caps worked , too
This really made me pull my hair out as these were new components .. replaced the bridge , checked the design ... who would of thought of bad new parts. Thought it was my stupidity , not bad parts. 20 pieces of junk for the landfill (below 2). ARGGGGGGG!!!!
PS. Right on, Dan. Mouser , panasonic and Nichicon .... no EBAY - no name junk. ohh , I'm soooooo mad !! (need a beer)
OS
I received a gift of 20 marcon (united chem-con) 470u@100v caps. Never used them until now. Fired up the Nikko power supply (below 1) and got magic smoke and popped caps !!!
You ARE right, Daniel , I must test every part I get... even new ones. These marcons were made in "china" DEFECTIVE JUNK even when new. In the first pix I put 2 panasonics in just to test and I got my 68v high voltage supply .... my sanwha caps worked , too This really made me pull my hair out as these were new components .. replaced the bridge , checked the design ... who would of thought of bad new parts. Thought it was my stupidity , not bad parts. 20 pieces of junk for the landfill
(below 2). ARGGGGGGG!!!!PS. Right on, Dan. Mouser , panasonic and Nichicon .... no EBAY - no name junk. ohh , I'm soooooo mad !! (need a beer)
OS
Attachments
Funny thing , they are rated 105° C....
The marking is suspect though, since i never saw the voltage specified
ahead of the capacity in well known manufacturers products....
Maybe old ??
They could be 1984 caps ?? (8406 code on them) I missed that and used them regardless. I looked up Nichicon and panasonic caps , they are a little smaller
(16 X 25mm vs. 16 X 32 mm for these units ). So I have to spend another $8 for my caps. That sucks , because i have everything else to build this amp .
PS - there was no little cap inside the big one.
OS
They could be 1984 caps ?? (8406 code on them) I missed that and used them regardless. I looked up Nichicon and panasonic caps , they are a little smaller
(16 X 25mm vs. 16 X 32 mm for these units ). So I have to spend another $8 for my caps. That sucks , because i have everything else to build this amp
.PS - there was no little cap inside the big one.
OS
Other "hints" ...
I ran them on a lower voltage trafo (20V) , they did not heat up. The ESR meter and my DMM showed they were good.... They charged and discharged as they should with the 9V of the DMM. Hooked them to a 68V supply ... BANG!! So maybe they are pirated lower voltage components (35v ??) Oh , the shame !!!
OS
I ran them on a lower voltage trafo (20V) , they did not heat up. The ESR meter and my DMM showed they were good....
They charged and discharged as they should with the 9V of the DMM. Hooked them to a 68V supply ... BANG!! So maybe they are pirated lower voltage components (35v ??) Oh , the shame !!!OS
Nah , I threw them out . If they were mis-marked like that, they might be inferior in other ways as well. I would not use them in my enemy's amp. I will get brand new 470/100V panasonics so I will not have any issue. I did not derate to 100V for 68V supplies only to use a component of unknown "virtue". I want my 20 full years MTBF !
OS
OS
Most probably, these are 50V remarked 100V.
Usually, for such caps, voltage specified is for 20uA max leaking current.
Manufacturers add at least 15/20% for safety, so a 50V cap will have the said
20uA leakage at about 60V, wich correlate with your 68V firing point.
Well for low voltage accessories, they would be enough, and since
you have a bunch of them, put 3 where one is needed !! one never knows...
Usually, for such caps, voltage specified is for 20uA max leaking current.
Manufacturers add at least 15/20% for safety, so a 50V cap will have the said
20uA leakage at about 60V, wich correlate with your 68V firing point.
Well for low voltage accessories, they would be enough, and since
you have a bunch of them, put 3 where one is needed !! one never knows...
I feel "violated"..
My first experience with fakes !!! So I learn. The anger , I wish I could physically shove the components in question directly down the throat of the CEO of the pirate cap organization ! In a critical application , someone might die (medical equipment). I will confine my sourcing to known distributors.
PS , they get warm with a 28 - 0 -28 Vac trafo , they must be a paltry 35V rating. (100V my ****)
OS
My first experience with fakes !!! So I learn.
The anger , I wish I could physically shove the components in question directly down the throat of the CEO of the pirate cap organization ! In a critical application , someone might die (medical equipment). I will confine my sourcing to known distributors. PS , they get warm with a 28 - 0 -28 Vac trafo , they must be a paltry 35V rating. (100V my ****)
OS
I wasn't really thinking caps, but rather what happens if just one fake/incorrect transistor gets into a high power amplifier and then your customer is going to tell you the sound sucks. Yeah, just one incorrect (either fake or authentic) transistor will do that. And, there's the additional problem of several versions for each identically/similarly named part. There's also: "Chinese Roulette"
P.S.
Going for the smaller, normal efficiency, low inductance caps, seems to suit that power board. The smaller variety of Panasonic FC is a decent example with high availability.
P.S.
Going for the smaller, normal efficiency, low inductance caps, seems to suit that power board. The smaller variety of Panasonic FC is a decent example with high availability.
