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Old 12th April 2010, 10:47 AM   #1
drjbf1 is offline drjbf1  New Zealand
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Default J-JLH or PLH-J ?

In the PLH article Nelson says:

"If you send me a bag of high power Jfets, Iíll supply a schematic that will work with them, too."

Has anyone seen such a schematic?
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Old 12th April 2010, 12:55 PM   #2
flg is offline flg  United States
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Only the "simplified" J2 as far as I have seen...
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Old 12th April 2010, 10:59 PM   #3
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I had forgotten that I made such a promise. It is, however
very do-able. All you have to do is send me that bag. I
cannot be expected to supply the high power Jfets as well...

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Old 12th April 2010, 11:13 PM   #4
Blues is offline Blues  United States
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Circuit should be reserved for the PL custom power jfets Maybe the color green will make it get to the production line sooner...
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Old 13th April 2010, 02:07 PM   #5
FYC is offline FYC  Hong Kong
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A step forward at least, is to replace the input IRF610 with a J-FET. I've done that and I do see an improvement. As a matter of fact, I put 2 2SK147 in parallel as the input stage in place of the IRF610.
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Old 13th April 2010, 09:32 PM   #6
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I have not tried it yet, but I would expect interesting results
with the SJEP170R550.

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Old 18th July 2011, 10:31 PM   #7
tmblack is offline tmblack  United Kingdom
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How would one make a PLH with a dual power supply?
In the article that was left as a future exercise.
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Old 18th July 2011, 10:32 PM   #8
tmblack is offline tmblack  United Kingdom
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Quote:
Originally Posted by FYC View Post
A step forward at least, is to replace the input IRF610 with a J-FET. I've done that and I do see an improvement. As a matter of fact, I put 2 2SK147 in parallel as the input stage in place of the IRF610.
How would the circuit change if any with the input J-FET ?
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Old 18th July 2011, 10:45 PM   #9
flg is offline flg  United States
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Quote:
Originally Posted by tmblack View Post
How would one make a PLH with a dual power supply?
In the article that was left as a future exercise.
The Class-A Amplifier Site Here you will find at least one version like that
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Old 19th July 2011, 07:43 PM   #10
sheep is offline sheep  Canada
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I'll work on the latest JLH dual supply version with power BJT's as I have a large supply and they are much cheaper. I'll add the current sources using DM2540 depletion FETS though.
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