Thank you John. Maybe in one of the magazines mentioned about
http://www.diyaudio.com/forums/soli...rrently-available-electr-audio-magazines.html
e. g. MJ magazine
Thank you for this short form data overviews. Are there also datas in the kind of those from follow URL?
http://www.onsemi.com/pub_link/Collateral/MJ21193-D.PDF
Maybe Tesla datasheets and databooks are only available in the native language - thus I don't know the right keywords for google.
I think the Czechia members and those from Slovakia and Poland/Russia can check out this.
Let's take your time for recheck that - it is not very much for me.
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I tried, but can't find all of the documents. What I can find out is this:
Homotaxial 2N3055 can't be directly replaced by modern production Epitaxial 2N3055 since they are far different. However, 1300pF 1MHz Homotaxial 2N3055 could be replaced by 1000pF 2MHz Epitaxial MJ15003, MJ802, MJ15001, which are sturdy, slow, high noise, high capacitance, high current devices. This sort of thing is suitable for repairs of Class A or high bias amplifiers.
thank you for this advices.
Are there any news in this case?
Toshiba 2N3055 Counterfeit - which real manufacturer ??
By chance I have found this:
Counterfeit transistors -
Hard to believe, that Toshiba was the manufacturer in real world.
By chance I have found this:
Counterfeit transistors -
Hard to believe, that Toshiba was the manufacturer in real world.
Just to show that the 3055 can work well for audio, here's a pair of new amplifiers with 3055's (and similar!).
Not currently in production, as far as I know.
Tringlophone, Class A, from Elvee
Tringlophone can use most output devices--the compensation will merely roll back a modern output device to approximately a 3055 speed anyway. There's no switching going on in class A, so really, the spec to look for in an output device for it, is linearity, such as the highly linear MJ21194.
And then. . .
Here's another new 2N3055 amplifier.
Circlophone, Class aA, from Elvee
Circlophone can use classic output devices of days gone by (modern equivalents of the classics are MJ802, MJ15001, MJ15002), or it can use more MJL21194, or it can use a much faster output device if when capacitance is added, C11, like this.
Circlophone was the first sliding bias Class A amplifier made adaptable to state of the art Class aAG (by adding two published mods that use a transistor each, and add the variable supply). That is a cell phone tower technology not yet used for linear audio. However, the two mods have been used to prevent rail voltage fluctuations from interposing a signal on the audio. One of these mods replaces the bias setting resistor with a CCS and the other mod replaces the zeners. After that, one could use the circlo with a variable supply, flimsy rails, or a Class G tracking power supply.
Elvee has BD249C on his personal Circlophone amplifier (although it was tested and measured with 3055's in place).
Several Circlophones have been built with classic output devices from junk boxes and likewise highly satisfactory circlos have been built with the MJ15003, the modern day equivalent of a classic output device.
This amplifier has tracking instead of switching, so really any sturdy and reasonably linear output device suits it.
Got some classic outputs that need employed? Try the circlo. The dynamics are a bit wild, so you won't get bored.
Not currently in production, as far as I know.
Tringlophone, Class A, from Elvee
Tringlophone can use most output devices--the compensation will merely roll back a modern output device to approximately a 3055 speed anyway. There's no switching going on in class A, so really, the spec to look for in an output device for it, is linearity, such as the highly linear MJ21194.
And then. . .
Here's another new 2N3055 amplifier.
Circlophone, Class aA, from Elvee
Circlophone can use classic output devices of days gone by (modern equivalents of the classics are MJ802, MJ15001, MJ15002), or it can use more MJL21194, or it can use a much faster output device if when capacitance is added, C11, like this.
Circlophone was the first sliding bias Class A amplifier made adaptable to state of the art Class aAG (by adding two published mods that use a transistor each, and add the variable supply). That is a cell phone tower technology not yet used for linear audio. However, the two mods have been used to prevent rail voltage fluctuations from interposing a signal on the audio. One of these mods replaces the bias setting resistor with a CCS and the other mod replaces the zeners. After that, one could use the circlo with a variable supply, flimsy rails, or a Class G tracking power supply.
Elvee has BD249C on his personal Circlophone amplifier (although it was tested and measured with 3055's in place).
Several Circlophones have been built with classic output devices from junk boxes and likewise highly satisfactory circlos have been built with the MJ15003, the modern day equivalent of a classic output device.
This amplifier has tracking instead of switching, so really any sturdy and reasonably linear output device suits it.
Got some classic outputs that need employed? Try the circlo. The dynamics are a bit wild, so you won't get bored.
The point of post#169:
I'm saying that the classic high capacitance output devices work perfectly well in amplifiers that don't make crispy sparky clipper-esque sounds of switching discharging the older device's high parasitic capacitance, and therefore the classic outputs work best in Class A, High-Bias-Ab, Class AA, Class aA and Class aAG. . . but not so well in Class aB (lowercase a indicates low bias) or D (lots of switching).
Question:
If we have, on hand, a new output transistor like MJ21194, 500pF but want to use it to repair an old amplifier with 3055H, 1500pF, can we not just add a 1n capacitor right at the new output transistor to basically mimic an older transistor, like 500p+1n=1500p, so that the new part will plug-n-play easily?
I'm saying that the classic high capacitance output devices work perfectly well in amplifiers that don't make crispy sparky clipper-esque sounds of switching discharging the older device's high parasitic capacitance, and therefore the classic outputs work best in Class A, High-Bias-Ab, Class AA, Class aA and Class aAG. . . but not so well in Class aB (lowercase a indicates low bias) or D (lots of switching).
Question:
If we have, on hand, a new output transistor like MJ21194, 500pF but want to use it to repair an old amplifier with 3055H, 1500pF, can we not just add a 1n capacitor right at the new output transistor to basically mimic an older transistor, like 500p+1n=1500p, so that the new part will plug-n-play easily?
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The covers are taller than average and the top is domed. If I get a reason to go inside that amp I'll get you a better shot.
I did find a mention somewhere on here that the Toshiba 2N3773 was actually a relabled 2SD873.
Member
Joined 2009
Paid Member
Have you any thoughts on the sound comparison between the JLH 10W Class A and the Circlophone based on 2N3055 outputs ?
if they are genuine toshiba devices (which they look to be) relabeling them from a 2SD number to an equivalent 2N number would have opened up a US military market for toshiba.... one thing about Toshiba is that they have a very comprehensive reliability tracking program, which mirrors reliability programs required for supplying US government contracts.
Yes one, the circlo has better dynamics than anything else, but tringlophone is more accurate. Tringlophone will best that jlh due to power circuit. I had minor tone trouble with my circlo although it did everything else optimally.
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Solist-100
Hi,
Here is "Solist-100" guitar-amp from Melodija Mengesh (YUG).
http://perotron.files.wordpress.com/2012/07/solist-100_v-0-2.png
http://perotron.files.wordpress.com/2012/07/solist-100_v-0-2_razmestaj_sa_oznakama.png
http://perotron.files.wordpress.com/2012/07/solist-100_01.jpg
Any coment
Hi,
Here is "Solist-100" guitar-amp from Melodija Mengesh (YUG).
http://perotron.files.wordpress.com/2012/07/solist-100_v-0-2.png
http://perotron.files.wordpress.com/2012/07/solist-100_v-0-2_razmestaj_sa_oznakama.png
http://perotron.files.wordpress.com/2012/07/solist-100_01.jpg
Any coment
Member
Joined 2009
Paid Member
So even the humble 2N3055 can perform very well.
What makes the circle so dynamic ?
I am wanting to set up this amplifier for SHURE PA, liked the application NBF, but I'm wanting to use the power voltage + B twice.
Can anyone comment?
http://55d5340a043a828856e1-f62de27...om/user_guide/upload/1294/us_pro_pm300_ug.pdf
Can anyone comment?
http://55d5340a043a828856e1-f62de27...om/user_guide/upload/1294/us_pro_pm300_ug.pdf