Thank you Prasi
Just the front panel, the top and the other parts supposed to be metal, aluminium would be best
i am interested to try this version of the amp using 2sc5200 and Lt 1083 regulated supply.
Do i need to change other values if i want to use a 24V dc power supply build for F5??
DIY Kit Hood 1969 Class A 5200 Power Amplifier Board Kit With 1083 Regulated | eBay
Do i need to change other values if i want to use a 24V dc power supply build for F5??
DIY Kit Hood 1969 Class A 5200 Power Amplifier Board Kit With 1083 Regulated | eBay
I have to start to etch the PC boards and go on with these project. Same time I etch PC boards for a dozen other amplifiers. I need to rebuild the amplifier case I used US standard screws and they loosen up (my heat sinks are heavy) if I tide the screws harder it damage the taping. I purchased from China M6 tap true Ebay to re tap the heatsink and waited 2 mounts to receive it.
Meanwhile I put together another amplifier case but to big to use for these (would be waste) project, I think that can handle 50-60W Class A PP amplifier like the KSA 50.
Now no more excuse I have to start to put these amp together.
Greetings gabor
Good to see you are still here Gabor.
-Dan
Yes I am here but the same time (almost not here)I having very little progress. I am (or I was) a disabled person. The last several mounts I spent with doctors to do check ups to fill up my forms for my disability support. Still not finished yet, at December I will have to do two MRI tests and some other to. Unfortunately I already know the Canadian government does not care much how sick or ill someone
since they cut my benefit. Now I have to re-appeal against their decision. Tomorrow I go to see a lawyer. So I am very busy with all these and unfortunately not much progress with my DIY audio projects (amps, speakers etc,) I want to say to those who wait on my progress report sorry guys unfortunately there are other priorities at these moment in my life. I know I started several project and most of them not finished because the mentioned situation. Greetings to all
Look after yourself Gabor I hope your situation Improves.Yes I am here but the same time (almost not here)I having very little progress. I am (or I was) a disabled person. The last several mounts I spent with doctors to do check ups to fill up my forms for my disability support. Still not finished yet, at December I will have to do two MRI tests and some other to. Unfortunately I already know the Canadian government does not care much how sick or ill someone
Greetings to all
-Dan
Hi.
I would like to build a jlh amplifier and I have few questions.
Is it possible to use modern transistors with higher fT (I have some 2sc5200 and lots of Russian kt's with fT=20MHz)? I read somewhere that it oscillates with higher fT transistors. Is it true? This amp has lot of versions. Which one sounds best in your opinion (propably one without cap on output ) ?
Greetings from Poland.
Oskar
I would like to build a jlh amplifier and I have few questions.
Is it possible to use modern transistors with higher fT (I have some 2sc5200 and lots of Russian kt's with fT=20MHz)? I read somewhere that it oscillates with higher fT transistors. Is it true? This amp has lot of versions. Which one sounds best in your opinion (propably one without cap on output
) ?Greetings from Poland.
Oskar
Hi.
I would like to build a jlh amplifier and I have few questions.
Is it possible to use modern transistors with higher fT (I have some 2sc5200 and lots of Russian kt's with fT=20MHz)? I read somewhere that it oscillates with higher fT transistors. Is it true? This amp has lot of versions. Which one sounds best in your opinion (propably one without cap on output
Greetings from Poland.
Oskar
,for me,MJ15003 is the best for JLH amp 69 version .
y have one version with sc5200 ,one with mj15024,one with BDX50 and definitively,y prefere the mj15003
I would like to build one without cap on output so it can't be '69 version
https://www.google.fr/url?sa=t&rct=...mplifier.pdf&usg=AOvVaw2E0I4plI0mFISMfLgppULp
Ok. Now I know where i read that it oscillates with higher fT transistors
It is possible to use higher fT transistors. I've mentioned this before (probably earlier in this thread) that to do so requires a small capacitor (33pF in my case) across the feedback resistor to correct the gain/phase response. At least in the original design - I have not tested it with the DC coupled version, but I suspect the same applies.
But the biggest concern with the high fT transistors is the very high input capacitance.
They really need fairly powerful driver transistors.
So it would seem that older style devices might still be preferable for the JLH Class A such as MJ15003 or perhaps TIP3055's.
But the biggest concern with the high fT transistors is the very high input capacitance.
They really need fairly powerful driver transistors.
So it would seem that older style devices might still be preferable for the JLH Class A such as MJ15003 or perhaps TIP3055's.
Thank you very much for help .
I've got some more questions . Probably somewhere in this veeerrrryyy long thread somebody (I hope ) posted pcb in pdf for 2003 version. Am I right ? Honestly...I would have to spend a week or so to read it from beginning ...so does somebody have a pcb for 2003 version in pdf, jpg etc.? Unfortunately when I type pcb or pdf in "search this thread" nothing pops up .
. I've got some more questions
. Probably somewhere in this veeerrrryyy long thread somebody (I hope ) posted pcb in pdf for 2003 version. Am I right ? Honestly...I would have to spend a week or so to read it from beginning ...so does somebody have a pcb for 2003 version in pdf, jpg etc.? Unfortunately when I type pcb or pdf in "search this thread" nothing pops up .Has somebody compared some version of jlh to some other amps? I'd like to build a class A amp . I have Pass Zen already. Will JLH be comparable with Zen in term of sound quality?
Also I've found something like this: NOStalgia - the all-FET JLH/PLH Class A amplifier it's a fet version of JLH. What do you thing about it?
. I have Pass Zen already. Will JLH be comparable with Zen in term of sound quality?Also I've found something like this: NOStalgia - the all-FET JLH/PLH Class A amplifier it's a fet version of JLH. What do you thing about it?
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Just mention that "The Class-A amplifier site" is always worth looking at if you are contemplating starting a JLH 10 watt amp'.. It is very thorough in looking at a lot of options, build notes, reviews etc. And it contains the original article (1969) the subsequent postscript (1970) and the split rail upgrade (1996). (It also has other class A amps etc. Well worth a visit if you don't know it)
It was developed by Geoff Moss in the UK and for some years has been hosted by Elliot Sound Products here in Australia. That is where Oskar2905 gave us the link above.
Merry Christmas to all the JLH devotees.
Cheers, Jonathan (proud owner of a '69 version for 40 yrs)
It was developed by Geoff Moss in the UK and for some years has been hosted by Elliot Sound Products here in Australia. That is where Oskar2905 gave us the link above.
Merry Christmas to all the JLH devotees.
Cheers, Jonathan (proud owner of a '69 version for 40 yrs)
pcb pdf and gerbers..Thank you very much for help
I've got some more questions
JLH 10 Watt class A amplifier
Thank you for a very useful site
.Thank you for the pcb
. It's too big for a one piece of A4? Am I right :/ ?
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