I will take 2 for myself. The thing I was wondering was if it would be less expensive to have them shipped with a bulk order of Avels going to the USA office. Yes, the office here is a stocking office for standard trannies so they must occasionally be shipping orders here. I just think it would be less expensive to ship them this way than to ship individually at great cost. I would expect more than 100.00 U.S. just in shipping if you were to send em straight to me yourself.
Mark
Mark
Regarding the boards:
Is there still somebody out there that hasn't received his boards or am I the only unlucky guy 🙁
Regards
Is there still somebody out there that hasn't received his boards or am I the only unlucky guy 🙁
Regards
GeWa said:
You're not alone.
This is Mark's response to my e-mail on Feb 19, 2007.
"Hi Farl,
Have not yet shipped your baords yet due to heavy
work load. I will send the boards and the diodes
together as soon as I am back in town.
Best regards,
Mark"
Regards
At least you know that they still have to be shipped. According to Mark my boards are in the mail for quite some time now so I'm starting to get a little worried.
Regards
Regards
GeWa -
I understand your frustration waiting for your boards, but it would have been more appropriate to say "Mark shipped mine a while ago and ..." I will assume that you didn't mean to suggest that Mark has been anything but honest, but your post sounds a bit that way (at least before coffee 😉 ).
Mark has shipped out more than his share of boards on various buys. From what I have seen, any issues tend to be resolved in the buyer's favor.
Thanks for your efforts Mark. I know how hard it is to get group buy stuff out when the you-know-what hits the fan at your day job.
Bob (who has beautiful boards in hand)
I understand your frustration waiting for your boards, but it would have been more appropriate to say "Mark shipped mine a while ago and ..." I will assume that you didn't mean to suggest that Mark has been anything but honest, but your post sounds a bit that way (at least before coffee 😉 ).
Mark has shipped out more than his share of boards on various buys. From what I have seen, any issues tend to be resolved in the buyer's favor.
Thanks for your efforts Mark. I know how hard it is to get group buy stuff out when the you-know-what hits the fan at your day job.
Bob (who has beautiful boards in hand)
It's about time than that you get that cup of coffee Bob. In no way I'm blaming Mark for this nor am I insinuating that Mark is dishonest in any way, let's get this strait. I'm sorry if my post came out otherwise.
Regards
OK - I just wanted to make sure that nobody else made the same mistake I did. Sorry I was cranky.
I am in Red Lodge, MT right now till Tuesday. But will look into it as soon as I get back into town.
Mark
Mark
Re: samples
If you are interested Mark, I can ship 4 pair of the Toshiba 2SA1837/2SC4793 if you would like to test them against yours. PM me your address if need be.
Thanks Loek, Yes I will do it but I dont think they will ship a 50 pair for free, But I should try a smaller amount or try to buy a "Samples Batch" from them.
Regards
😎
Ok, I will check for that but first I would like to start a GB in the Market Place to see if other Krell Clone builders are interested to receive an original Krell transformer for "not for free", yes they cost a lot, but they are the best available for an amp like this. (including yours Mark, we have 6 pcs to order @ first price brake) 🙂Mark A. Gulbrandsen said:
If you are interested Mark, I can ship 4 pair of the Toshiba 2SA1837/2SC4793 if you would like to test them against yours. PM me your address if need be.
Jakko, I had an information that said those 2SA1837/2SC4793 was a direct replacement for the older 2SA938/2SC2238? Correct me if Im wrong please.jacco vermeulen said:
loek said:
Thanks Loek, Yes I will do it but I dont think they will ship a 50 pair for free, But I should try a smaller amount or try to buy a "Samples Batch" from them.
Regards
😎
I dont think they will ship a 50 pair for free
Hi Flodstroem, i asked 20pcs of each 2110 and i got 80 for free. But i did it with my job(university)address....
Maybe it is also possible to order them as "private" samples.
Loek
Hi Flodstroem, i asked 20pcs of each 2110 and i got 80 for free. But i did it with my job(university)address....
Maybe it is also possible to order them as "private" samples.
Loek
Re: I dont think they will ship a 50 pair for free
Hi Loek
Thanks for your information.
Forgot to mention I own a business and usually I ask for samples in my companies name, not as a private.
Yes it might go if I ask for, say 20-80 pcs as in your case? I will try it. Regards 😎
loek said:
Hi Loek
Thanks for your information.
Forgot to mention I own a business and usually I ask for samples in my companies name, not as a private.
Yes it might go if I ask for, say 20-80 pcs as in your case? I will try it. Regards 😎
Flodstroem said:
In terms of Vce, hFe and safe operation area(max current), Yes.
Other parameters, No.
In one case the replacements are an improvement, in other cases they are not.
Just as there may be a type from a different manufacturer which is better than originals or same brand replacements.
Rectifying Diodes
I would like to use the MUR1520 diodes configured for two bridges per side plus soft start. These are rated at 15 Amps each.
Is the current rating enough or should I use four 30A 1000V bridges?
Thx
I would like to use the MUR1520 diodes configured for two bridges per side plus soft start. These are rated at 15 Amps each.
Is the current rating enough or should I use four 30A 1000V bridges?
Thx
Harry,
usually one learns to drive before designing a car himself.
Or at least read the manual first.
Such diodes handle a couple of hundred amps peak.
Suppose you have 2.5 bias amps flowing continuously through the diode, which isn't the case in reality.
At 100C, diode voltage drop at 2.5 amps current is in the 0.6 volts ball park, 2.5 times 0.6 means 1.5 watts of dissipation.
An MUR1520 is comparable with a transistor, the larger the heatsink you attach it to, the more power it can handle.
At 60C above ambient, a 37.5C/W heatsink would be sufficient to handle the 1.5 watts.
As this is a Krell, you can stick the diode to a fat B heatsink for the MUR1520 to handle sheer idiot peak currents.
Such diodes are capable of handling square wave signals in switchmode powersupplies, a Krell isn't that.
1520 means 15 amps continuous and 200 volt, whatever you need a 1000 volts for ?
A bridge rectifier is not 1 single diode, it has 4. Means the dissipation is shared between 4 diodes.
The peak current capability is far more than needed to handle the switch-on surge current levels.
Back in ancient times, a plastic block rect. bridge easily coped with a 100 watt class AB power amp.
For class A amps the sensible thing was to choose a square metal rectifying bridge, to attach it to a heatsink or case easily.
That was long before the fast switchmode diodes entered the scene. The 15 amps is continuous current draw through the diode, at a 150C temperature, and it's an average current level on top of that.
usually one learns to drive before designing a car himself.
Or at least read the manual first.
Such diodes handle a couple of hundred amps peak.
Suppose you have 2.5 bias amps flowing continuously through the diode, which isn't the case in reality.
At 100C, diode voltage drop at 2.5 amps current is in the 0.6 volts ball park, 2.5 times 0.6 means 1.5 watts of dissipation.
An MUR1520 is comparable with a transistor, the larger the heatsink you attach it to, the more power it can handle.
At 60C above ambient, a 37.5C/W heatsink would be sufficient to handle the 1.5 watts.
As this is a Krell, you can stick the diode to a fat B heatsink for the MUR1520 to handle sheer idiot peak currents.
Such diodes are capable of handling square wave signals in switchmode powersupplies, a Krell isn't that.
1520 means 15 amps continuous and 200 volt, whatever you need a 1000 volts for ?
A bridge rectifier is not 1 single diode, it has 4. Means the dissipation is shared between 4 diodes.
The peak current capability is far more than needed to handle the switch-on surge current levels.
Back in ancient times, a plastic block rect. bridge easily coped with a 100 watt class AB power amp.
For class A amps the sensible thing was to choose a square metal rectifying bridge, to attach it to a heatsink or case easily.
That was long before the fast switchmode diodes entered the scene. The 15 amps is continuous current draw through the diode, at a 150C temperature, and it's an average current level on top of that.
Well, I'm home and the 1N5309 diodes are here! This has got to be the largest single order Mouser has ever shipped of these🙂.
I will sort them out and get them shipped over the next few days. I will send Jacco the lot for the European and Scandanavian continents to ship and I will also PayPal him the funds. I will ship the rest of em out to US, Austrailia and Canada...
Mark
I will sort them out and get them shipped over the next few days. I will send Jacco the lot for the European and Scandanavian continents to ship and I will also PayPal him the funds. I will ship the rest of em out to US, Austrailia and Canada...
Mark
Hey Mark-
Your email through the forum is disabled. Would you mind dropping me an email? Just a quick question.
Your email through the forum is disabled. Would you mind dropping me an email? Just a quick question.