Thanks Sakis....
Yes I agree transformer too small only 10A CT47Vac...but only this I have...In my place..too hard to find good toroid with big ampere (power). In the electronic shop alot of sale toroid from China ...I thinks not so good...Any way..in some electronic shop ready EL transfrmer with bigger body..not enough for 2U box...
Please info: can I placed TR predriver on main HS? What happen if I do it??
Sorry my english...😉
Regards
I repeat againt for Apex...to confirm this: Can I placed TR predriver (MJE340/350) on main heatshink? What happen if I do it?
Pozdrav...
Pozdrav...
i can put a trimpot in place of R23 for adjustments?
and DC settings, where can I put a trimpot?
and DC settings, where can I put a trimpot?
Trimpot 100R with 220R in series instead R23 (330R) can use for bias adjust.
Circuit with R10,R11,C8,C9 is used for auto adjust DC offset.
Hi..Apex..one question:
After I operation B500 and power off...just led indicator clipping "on" immediatly..flassh..What wrong this PA?
This PA unused softstar and PSU unused R snubber (47K/1W)..
Regards,
Electra
After I operation B500 and power off...just led indicator clipping "on" immediatly..flassh..What wrong this PA?
This PA unused softstar and PSU unused R snubber (47K/1W)..
Regards,
Electra
Well, now no more doubt, I will now buy the components, with you say, it is not better than crown or crest, but it comes close, huh?
i can separate the PCB into two parts? one with only the power transistors and emitter resistors, and the other with the rest, but the driver and MJE340 MJE will be in the same sink of power, like to separate to make it easier to make the PCB and mount to the chassis between them the maximum distance is only 2 or 3 inches
last question, promise not to tell anything more! hhehehe
I can put on each base of the transistors of an output resistor of low value, at 4.7 R, the current split is better ok? .. it helps, hinders, or changes nothing about this amp?
i can separate the PCB into two parts? one with only the power transistors and emitter resistors, and the other with the rest, but the driver and MJE340 MJE will be in the same sink of power, like to separate to make it easier to make the PCB and mount to the chassis between them the maximum distance is only 2 or 3 inches
last question, promise not to tell anything more! hhehehe
I can put on each base of the transistors of an output resistor of low value, at 4.7 R, the current split is better ok? .. it helps, hinders, or changes nothing about this amp?
Best thing in DIY is that you can do anything what you want, you have no response to anybody exsept yourself.
Regards
Sorry Apex..too late posting this picture..😉
This is wiring and grounding my B500:
http://upload.kapanlagi.com/h/20100610150104_B500grounding_4c109bc037644.jpg
I usualy make central ground on psu pcb, but gnd connect to case near input terminals not from psu, from psu gnd to case connect 100nF cond.
nao to pico convertion
apex,
sir can you please help me with converting this nanofarad caps to picofarad???...
we are trying to build your 500w pa amp...but nanofarad is not available in our place...would ceramic caps do the job or mylar ones???...
100nf = pF?...
47nF = pF?...
10nF= pF?...
tnx...
apex,
sir can you please help me with converting this nanofarad caps to picofarad???...
we are trying to build your 500w pa amp...but nanofarad is not available in our place...would ceramic caps do the job or mylar ones???...
100nf = pF?...
47nF = pF?...
10nF= pF?...
tnx...
This is usually notification for caps:
100nF - 0,1uF
47nF - 0,047uF
10nF - 0,01uF,
Regards
100nF - 0,1uF
47nF - 0,047uF
10nF - 0,01uF,
Regards
Last edited:
nF was formerly known as kpF, that is, 1nF=1kpF=1000pF.
So, 100nF means 100kpF, or 100 000pF;
47nF means 47kpF, or 47 000pF;
10nF means 10kpF, or 10 000pF.
Regards,
Max.
