Howdy -
I have a problem with my left channel of my JLH 80 watter. It's the last single PCB Wiliams Hart version - not the Hart version with separate boards for power supply & amplifier.
Does anyone have a copy of the kit instructions with circuit diagram & parts list for the Williams Hart incarnation of the JLH 80 watt amp (mono or stereo - it's the same board).
I would be so grateful if someone could help me out - There's a bottle of your favourite tipple in it -
I love these amps and while I ordered the kit, it took so long to arrive (parts out of stock) that they sent me a ready built set with no instructions.
my e mail is
iestyn.morris@quiksilver-europe.com
Any help much appreciated.
I have a problem with my left channel of my JLH 80 watter. It's the last single PCB Wiliams Hart version - not the Hart version with separate boards for power supply & amplifier.
Does anyone have a copy of the kit instructions with circuit diagram & parts list for the Williams Hart incarnation of the JLH 80 watt amp (mono or stereo - it's the same board).
I would be so grateful if someone could help me out - There's a bottle of your favourite tipple in it -
I love these amps and while I ordered the kit, it took so long to arrive (parts out of stock) that they sent me a ready built set with no instructions.
my e mail is
iestyn.morris@quiksilver-europe.com
Any help much appreciated.
It looks like this :
J picture by bloodyhell451 - Photobucket
Hope you can see it - I'm new to photobucket.
Any help greatly appreciated -
Best regards,
rr
J picture by bloodyhell451 - Photobucket
Hope you can see it - I'm new to photobucket.
Any help greatly appreciated -
Best regards,
rr
Hi, just came across your post, I have reprints from ETI in my hand, but I'm not quite sure about the hart version. The one I have is with the cut out for the transformer. Not quite sure if I'm allowed to attach a file so I will send it to your email anyway.
Ignore what i just said, i just looked and there is no schematic, but wait just found one lying around in a cupboard
spin:
Ignore what i just said, i just looked and there is no schematic, but wait just found one lying around in a cupboardspin:As far as I know there are only two versions. The one with the cut-out on the power supply board and the one with all the gubbins on one board. We actually have 2 of the 35 watt versions, one stereo 80 watt version (single power supply) and two monoblock versions in our family. I'm the chump with the last Williams Hart one board version. By Bro has the twin board set of mono's and the other three amps are all back home with the folks. I also use the fully discreet phono pre amp & outboard power supply (as dos my Dad) and I have the full on pre-amp with outboard power supply as well. All were built by us axcept (guess what) my mono's.
When I get back to blighty I'm gonna scan everything a put it online for other disciples.
In the mean time I'd be very grateful for the one-board schéma & parts list. (number of resistor + value etc.)
There's a bottle in it !
When I get back to blighty I'm gonna scan everything a put it online for other disciples.
In the mean time I'd be very grateful for the one-board schéma & parts list. (number of resistor + value etc.)
There's a bottle in it !
The PCB was updated by Williams Hart electronics in the late 90's or early 2000's - third version. (Hart electronics was the original kit/PCB supplier that worked with JLH ) - Think one was '84 and then updated in '89 (PSU board wrapped around the toriodal etc and some updates. The very early ones I have seen photo's off. I have the later ones.
The reason for the new PCB (third) apparently, was that the performance was more built in - things like earthing etc, psu and amp on same PCB, and using newer plastic lateral mosfets (not T-O3). With the older PCBs there was alot you could do wrong constructing it if you where a novice.
It would be interesting to see some of the updates for the latest one. What values changed for DC offset, gain etc and PSU changes.
That's the one !
That's the boy ! Fanuc - do you (or does anyone) have the full blurb for this version ? Somebody please !
That's the boy ! Fanuc - do you (or does anyone) have the full blurb for this version ? Somebody please !
As a follow up - I had the Williams Hart mono fixed. It turns out that the output transistors had blown - taking out some zeners as well. The engineer had quite a time.
I can confirm that the circuit diagram and the parts list is the same for both versions - though the Hart version is closer to the original design - running a higher quiescent current than the Williams Hart. The heatsinking arrangements for the Hart are better - the L shaped plate in the Williams Hart version is not up to the same standard. This is going to be the subject of a futre project.
I can also confirm that APJ Audio
JLH 80W amplifier boards
is not only offering the boards for the Hart kit but is virtually able to supply complete Kits. I have ordered a power supply kit to turn a JLH Stereo Hart kit into a pair of Monoblocks. I don't think he has the transformer at the present time so that will have to be sourced elsewhere. I'll get back to you when I know more.
APJ Audio can also supply the construction manuals -
Thank god for this man ! Anyone interested in a pair of Monoblocks which can outperform commercial amplifiers up to £5000 (according to a friend who owns some very highly regarded examples of the breed) should give this man some custom !
Best regards
rr
I can confirm that the circuit diagram and the parts list is the same for both versions - though the Hart version is closer to the original design - running a higher quiescent current than the Williams Hart. The heatsinking arrangements for the Hart are better - the L shaped plate in the Williams Hart version is not up to the same standard. This is going to be the subject of a futre project.
I can also confirm that APJ Audio
JLH 80W amplifier boards
is not only offering the boards for the Hart kit but is virtually able to supply complete Kits. I have ordered a power supply kit to turn a JLH Stereo Hart kit into a pair of Monoblocks. I don't think he has the transformer at the present time so that will have to be sourced elsewhere. I'll get back to you when I know more.
APJ Audio can also supply the construction manuals -
Thank god for this man ! Anyone interested in a pair of Monoblocks which can outperform commercial amplifiers up to £5000 (according to a friend who owns some very highly regarded examples of the breed) should give this man some custom !
Best regards
rr
Does anyone have schematics for this version?
Hello,
Just wondering if anyone has the full schematics for this version. This is the third version. A copy of the assembly instruction schematic would be fine.
Sadly, that APJ audio does not seem to exist anymore.
Kevin
---------
PS. I am selling a Version 2 mono's (not the above PCB version) with regulated PSU PCB. Was going to make more of them for 5.1 sort of thing but never bothered.
http://www.diyaudio.com/forums/swap-meet/235432-jlh-eti-mosfet-amplifier-most-essential-kit.html
Hello,
Just wondering if anyone has the full schematics for this version. This is the third version. A copy of the assembly instruction schematic would be fine.
Sadly, that APJ audio does not seem to exist anymore.
Kevin
---------
PS. I am selling a Version 2 mono's (not the above PCB version) with regulated PSU PCB. Was going to make more of them for 5.1 sort of thing but never bothered.
http://www.diyaudio.com/forums/swap-meet/235432-jlh-eti-mosfet-amplifier-most-essential-kit.html
Last edited:
linsley hood 75 watt amp
I had a powertran kit deluxe. It had several serious flaws that meant the amp was always on the edge of blowing. the construction was put in too thin a box that provided insufficient heat sinking. also the boards were overly complicated in 3 sections that could twist.
i redesigned the boards completely to end up with a monoblock. the power supply board was redesigned and i have photos of the board design that allows one to be etched.
i am currently selling the amp to get one matching the tv. this has been working probably from 1994 with no problems.
linsley hood audiophile power amp with sub amp | eBay
charlie
I had a powertran kit deluxe. It had several serious flaws that meant the amp was always on the edge of blowing. the construction was put in too thin a box that provided insufficient heat sinking. also the boards were overly complicated in 3 sections that could twist.
i redesigned the boards completely to end up with a monoblock. the power supply board was redesigned and i have photos of the board design that allows one to be etched.
i am currently selling the amp to get one matching the tv. this has been working probably from 1994 with no problems.
linsley hood audiophile power amp with sub amp | eBay
charlie
Like this
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To add a photo, files or non standard files.
First click "go advanced" in the box below the "quick reply" message box. Doesn't matter if you decide half way through a message to do that, it carries it forward.
Then click "Manage attachements". Maximise the new Window so that you can see all the text.
Click browse in the first box at the top and find your picture. Repeat for any more pictures.
Click upload... a message appears "uploading"
When complete the files will show as being attached. Now click the small text that says "close this window"
The pictures should now be attached and when you submit your post they will appear.
Make sure your pics aren't too big, a couple of 100k is plenty, and many members object when they are massive and it alters the margins
It tells you in the attachments window what max sizes are allowed.
If you want to attach a file that has a non standard format for example excel, circuit simulation etc then try putting the files in a zipped folder and attaching that.
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