Digi Key
Hello Mike
This is funny, I ordered the transistors on the 25th and they
sent me the tracking number of the package today, it's
UPS (as I usually order by) but the number doesn't work.
I'm surprised because Digi Key has been very reliable so far.
Pretty darn fast service to Germany, faster than USA. Oh well!
Cheers
Hello Mike
This is funny, I ordered the transistors on the 25th and they
sent me the tracking number of the package today, it's
UPS (as I usually order by) but the number doesn't work.
I'm surprised because Digi Key has been very reliable so far.
Pretty darn fast service to Germany, faster than USA. Oh well!
Cheers
A lot of times UPS won't have the tracking number in their system until hte next day. I'd try again in the morning if I were you.
Thanks Mike for the answer. I will go with the 1302/3281
Blessings, Terry
Thanks Mike for the answer. I will go with the 1302/3281
Blessings, Terry
Digi Key
Guess what?
They told me that the tracking number worked for them and the package will be delivered on the 6th of December. Surprise,
surprise, it didn't work for me today again.
In any case if this is correct it's going to be around 12 days
the time lag of the deliver. Much worst than to Germany, he, he...
It's interesting because this never happened before with Digi
Key, must be because of the proximity of Christmas, I don't know!
Anyway I'm not desperate about the transistors, the amplifier
is working with the other ones .
Guess what?
They told me that the tracking number worked for them and the package will be delivered on the 6th of December. Surprise,
surprise, it didn't work for me today again.
In any case if this is correct it's going to be around 12 days
the time lag of the deliver. Much worst than to Germany, he, he...
It's interesting because this never happened before with Digi
Key, must be because of the proximity of Christmas, I don't know!
Anyway I'm not desperate about the transistors, the amplifier
is working with the other ones .
Nothing so good as see friends together, a good lunch and observing AKSA .
Reading a good thread, having nice food and watching wonderfull amplifier.
This is the Sixth amplifier made.... my twelve channels are near to born..... having Aksa, Symassym and Gem.
cheers,
Carlos
Reading a good thread, having nice food and watching wonderfull amplifier.
This is the Sixth amplifier made.... my twelve channels are near to born..... having Aksa, Symassym and Gem.
cheers,
Carlos
Attachments
Re: Digi Key
Hi John, this is really odd, i placed my order on a monday evening, a few hours later i got mail that the parcel is on it's way, and wednesday morning i had it in my hand. Maybe UPS is too busy with christmas...
The "other ones", are these the Sankens ?
Hey Carlos, "watching wonderful amplifiers", what have you eaten ? Amplifiers are for listening... 😀
Mike
jmateus said:
Hi John, this is really odd, i placed my order on a monday evening, a few hours later i got mail that the parcel is on it's way, and wednesday morning i had it in my hand. Maybe UPS is too busy with christmas...
The "other ones", are these the Sankens ?
Hey Carlos, "watching wonderful amplifiers", what have you eaten ? Amplifiers are for listening... 😀
Mike
Hi John,
I would call DigiKey and ask them. I bet you will receive the package sooner than you are being told.
Blessings, Terry
I would call DigiKey and ask them. I bet you will receive the package sooner than you are being told.
Blessings, Terry
Symsym
Yes Mike, those are the 2SC3857/2SA1493... They sound fine
but to have this pair I had to buy the 1493 that cost me $11.00
a piece, I mentioned that to you. And I bought them because I
have a load of 2SC3857 and I didn't have the complement. It
was worth but man, $11.00 for a transistor (I bought 2 only)
ouch, it hurts.
But no more, I just wanted to hear how those were going to sound, I'm satisfied now, the ones I didn't try yet are the 1943/
/5200, I'm anxious indeed but DigiKey is doing a number on me.
Perhaps I should do what Terry told me, I should call them.
I'm gonna do that tomorrow morning.
Yes Mike, those are the 2SC3857/2SA1493... They sound fine
but to have this pair I had to buy the 1493 that cost me $11.00
a piece, I mentioned that to you. And I bought them because I
have a load of 2SC3857 and I didn't have the complement. It
was worth but man, $11.00 for a transistor (I bought 2 only)
ouch, it hurts.
But no more, I just wanted to hear how those were going to sound, I'm satisfied now, the ones I didn't try yet are the 1943/
/5200, I'm anxious indeed but DigiKey is doing a number on me.
Perhaps I should do what Terry told me, I should call them.
I'm gonna do that tomorrow morning.
Hi !
New PCB is about to be finished, measuring should be done by ~tomorrow. 🙂 I hope it fixed the problem, if not, a complete redesign will be necessary...
I also added pins for REs in the input-ltp, these will become handy for versions with lower gain, suitable to be driven by preamps.
Mike
New PCB is about to be finished, measuring should be done by ~tomorrow. 🙂 I hope it fixed the problem, if not, a complete redesign will be necessary...
I also added pins for REs in the input-ltp, these will become handy for versions with lower gain, suitable to be driven by preamps.
Mike
Attachments
Mike, fuses with sand are normally " T " type, you must to use " F " ones, if they should have sense... Also this type of rails input pins are declared for low current...
Hi Upupa,
i use these pins only to solder wire onto it, shouldn't they be strong enough in this case ?
The fuses are 2.5T, i calculated them for averagecurrent and not for peak current, and so used slow blow style, do you think this will still be a problem ? In theory i have averagecurrent of 2.6a with a full scale sinewave into 4 ohm. What size would you recommend for fast fuses ?
Mike
i use these pins only to solder wire onto it, shouldn't they be strong enough in this case ?
The fuses are 2.5T, i calculated them for averagecurrent and not for peak current, and so used slow blow style, do you think this will still be a problem ? In theory i have averagecurrent of 2.6a with a full scale sinewave into 4 ohm. What size would you recommend for fast fuses ?
Mike
IMHO T2.5A is horribly low value and may bring destroying problems, if one of the fuses fails. I use 6.3A, and have only +/-27V supply. Try dummy load, speaker is not a resistor, and some of the boxes have enormous Ipeak.
Based on experience with another amplifiers, I know that this 2.5A fuse will once blow (this may happen after 3 years, who knows), and I do not wish this situation to any user ....
Symasym
Hi Mike
I've been using 3 A GMA fuses in all my three amplifiers, fast blow...
They seem to be working fine but is this a reasonable size in
case of a surge in power? You talk of an average of 2.6 A, so
I can assume 3 A would cover this average, wouldn't it?
BTW there is not too much difference in this new board and
the previous one, at least it doesn't seem to be, except may
be the provision for a ground (thick) bar completing the ground bus. There are two more jumpers which I can't see very well
by the picture; but I'm going to wait for your veredict after you
test the amp with these mods.
I forgot to tell you that I'm using +- 32V DC for the supply now
whereas the first amp had no more than 28V. A little bit more
power to the amplifier....even though I won't notice it because
I never play the amp at full power.
Thanks
Hi Mike
I've been using 3 A GMA fuses in all my three amplifiers, fast blow...
They seem to be working fine but is this a reasonable size in
case of a surge in power? You talk of an average of 2.6 A, so
I can assume 3 A would cover this average, wouldn't it?
BTW there is not too much difference in this new board and
the previous one, at least it doesn't seem to be, except may
be the provision for a ground (thick) bar completing the ground bus. There are two more jumpers which I can't see very well
by the picture; but I'm going to wait for your veredict after you
test the amp with these mods.
I forgot to tell you that I'm using +- 32V DC for the supply now
whereas the first amp had no more than 28V. A little bit more
power to the amplifier....even though I won't notice it because
I never play the amp at full power.
Thanks
Effective value of output current is 5 A for 100 W into 4 Ohm load, so it is 2.5 A for one rail. I'm using this value, F type and I have any problems with real boxes...
Don't forget that 2 months experience with the amplifieà is like nothing, you hardly get into all possible conditions ...
Every amp have by manufacturer defined working conditions, but not every possible conditions.... 😉
There is an amp I built in some 1986 and is still working. After some 8 years of operation it happenned that it blew the fuse, during normal operation to the loudspeaker, no short-circuit. No semiconductor failed, just blown fuse, rated this conservative way 😉 . I would rate the fuses higher and rather thing about current and DC protections 😉 , especially for the amp that is intended for public use.
Upupa Epops said:
You must take into account complex load, as every loudspeaker is. For this case and special frequency /decaying side of the resonance/ the peak current is in general twice the value you declare.