Ok...today i buy a few things...there's some that i can't find yet...but this ones give me some work to do for now...
I already buy the Fuses to...so late today i will start and test the power suply...
Regarding the TIP's i found the 2955 ones...any problem with different brand? thats wath i got...
Regarding the 7815/7915 whats the best way to test?
I already buy the Fuses to...so late today i will start and test the power suply...
Regarding the TIP's i found the 2955 ones...any problem with different brand? thats wath i got...
An externally hosted image should be here but it was not working when we last tested it.
Regarding the 7815/7915 whats the best way to test?
isc is inchange semiconductor.. a chinese company well known for making fake Sanken transistors.
The best way to test 7815 is to feed at least at least 18V into it, and see if a stable 15V comes out. Put some small load on the output e.g a 47 ohm 1W resistor for a current load of ~32mA. Similar for 7915. See their datasheets for the relevant info.
The best way to test 7815 is to feed at least at least 18V into it, and see if a stable 15V comes out. Put some small load on the output e.g a 47 ohm 1W resistor for a current load of ~32mA. Similar for 7915. See their datasheets for the relevant info.
So this ones will not serve...god damm :S make a mistake buying them..:S can you recommend a good ones from ebay or something?
Ok...you guys already recommend me this but the problem is the postage...and the minimum ammount in parts...:S that don't worth.... this is my problem....
I wouldnt be surprised if I found some NOS Motorolas here. Want some?
By the way: MJE2955T and MJE3055T will also be up to the job.
Originals is available "everywhere".
Also I can manage to get hold on some TIP2955/TIP2955 from ST. Around $5,-/each.
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I mean...i wanted to say...i found 2 ZTX753 only...this is the substitute for the 240 right? or for 239 ?
The RVs i found one made in spain almost the same size...and 1k i think they do the job:
An externally hosted image should be here but it was not working when we last tested it.
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Ok...already do a search on internet and replace the Q12/Q112 with ZTX753 replacement of FST240.
Already replace the following componnents too:
-- 2x FUSE 2A/250v - CHECK
-- 1x FUSE 630ma T - CHECK
-- Q12/Q112 FST240/ZTX753 - CHECK
-- R37/R137 15K - CHECK
-- D1/D101 1N4148- CHECK
-- C15/C115 22u/63v - CHECK
-- C16/C116 22u/63v - CHECK
-- RV1/RV101 -> 1k - CHECK
Since i already have the fuses i wanted to start testing the power supply, but i want to isolate the power circuit from the rest od the amp...can anyone help me indicating what "shunts" i need to cut to get abble to power on without any riscs for the rest of the circuits?
Already replace the following componnents too:
-- 2x FUSE 2A/250v - CHECK
-- 1x FUSE 630ma T - CHECK
-- Q12/Q112 FST240/ZTX753 - CHECK
-- R37/R137 15K - CHECK
-- D1/D101 1N4148- CHECK
-- C15/C115 22u/63v - CHECK
-- C16/C116 22u/63v - CHECK
-- RV1/RV101 -> 1k - CHECK
An externally hosted image should be here but it was not working when we last tested it.
Since i already have the fuses i wanted to start testing the power supply, but i want to isolate the power circuit from the rest od the amp...can anyone help me indicating what "shunts" i need to cut to get abble to power on without any riscs for the rest of the circuits?
Solder leads to an ordinary brakelightlamp from a car, 12V21W should do.
If everything is OK, this lamp will just glow very weak.
If it lits up strong there is some issues that makes the amp draw more than an amp or so.
If it blows, well, there is soething serious going on.
Turn the bias pots to minimum resistanse before starting up. (RV1, RV101.)
If everything is OK, this lamp will just glow very weak.
If it lits up strong there is some issues that makes the amp draw more than an amp or so.
If it blows, well, there is soething serious going on.
Turn the bias pots to minimum resistanse before starting up. (RV1, RV101.)
But i can turn this on without isulate the rest of the circuits? I mean i still miss a lot of componnets..there's no problem with that?
I will not take the risk...so i make some calls...hope this week anyone give some news regarding the ZTX653.....
A little update...just found some good ST's 
I already have almost everything...the ZTX's 653 i make a order...so i'm waiting for them...
There's only one question regarding the following resistors:
R35/135
R28/128
I can't find that 270R's in local dealer with 5% tolerance...
But i have at home some with 1% tolerance...the blue ones...can i use it in place of the others? Any disadvantages?
An externally hosted image should be here but it was not working when we last tested it.
I already have almost everything...the ZTX's 653 i make a order...so i'm waiting for them...
There's only one question regarding the following resistors:
R35/135
R28/128
I can't find that 270R's in local dealer with 5% tolerance...
But i have at home some with 1% tolerance...the blue ones...can i use it in place of the others? Any disadvantages?
1% tolerance is better than 5% tolerance so they will be fine.
I had to laugh but it's a bit like saying I cant find a 1L bucket, will a 5L bucket hold the same liquid.
Just make sure they are of an adequate size. Not physically but electrically. If the originals were 0.25W then anything bigger will do the job better.
Many years ago the commonplace resistor was 5% 0.25W - nowadays we are seeing more 1% 0.6W which are better.
I had to laugh but it's a bit like saying I cant find a 1L bucket, will a 5L bucket hold the same liquid.
Just make sure they are of an adequate size. Not physically but electrically. If the originals were 0.25W then anything bigger will do the job better.
Many years ago the commonplace resistor was 5% 0.25W - nowadays we are seeing more 1% 0.6W which are better.
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