Tube Recto JMP 50

gibboau · Post by **gibboau** » Thu Feb 22, 2007 1:13 am

Hi guys, this is my 1st post in this forum. First of all id like to thank all of you for the great informational posts on the forum, I

MacGaden · Post by **MacGaden** » Thu Feb 22, 2007 6:09 am

Wellcome to the board !

It

Post by **Brian Wallace** » Thu Feb 22, 2007 7:15 am

[quote]Of course I

MacGaden · Post by **MacGaden** » Thu Feb 22, 2007 10:09 am

Hi Brian:

Is the 100v tap the only difference between the 784-128 and 784-139 OT ?
Would a 784-139 work in a JTM50 ?

To the original poster: Another thing you could try if what you

gibboau · Post by **gibboau** » Thu Feb 22, 2007 4:02 pm

Hi guys thanks for the posts, seems like it would be easier to build Georges PTP kit, just trying to keep it simple the 1st time round

but here is the link to the layout of the 68 tube recto:
http://homepage.mac.com/gaden/.Public/jmp50_1968.jpg

also did some searching and found a guy on this forum who has a early 68 with a tube recto.. I've had a quick look and compared the JTM45 layout with the one above and there are common components.

eager to get my fiddy-watt started

mike

MacGaden · Post by **MacGaden** » Thu Feb 22, 2007 5:05 pm

gibboau wrote:Hi guys thanks for the posts, seems like it would be easier to build Georges PTP kit, just trying to keep it simple the 1st time round

but here is the link to the layout of the 68 tube recto:
http://homepage.mac.com/gaden/.Public/jmp50_1968.jpg

also did some searching and found a guy on this forum who has a early 68 with a tube recto.. I've had a quick look and compared the JTM45 layout with the one above and there are common components.

eager to get my fiddy-watt started

mike

That

gibboau · Post by **gibboau** » Fri Feb 23, 2007 12:21 am

hey MacG, thats a great site... great layouts!! any idea where that tube recto JMP layout come from?

Flames1950 · Post by **Flames1950** » Fri Feb 23, 2007 7:27 am

It was drawn up by a guy that posts at Plexi Palace, when the amp was on his bench getting some work done. His name is in the corner of the drawing.

MacGaden · Post by **MacGaden** » Fri Feb 23, 2007 7:42 am

gibboau wrote:hey MacG, thats a great site... great layouts!! any idea where that tube recto JMP layout come from?

Billy Batz has access, and can post there. Somebody must have asked for it.

Flames1950 wrote:It was drawn up by a guy that posts at Plexi Palace, when the amp was on his bench getting some work done. His name is in the corner of the drawing.

Ahh yes: The "Joint" caps layout, now I remember !

It says it

Post by **Brian Wallace** » Fri Feb 23, 2007 7:59 pm

I really don't care for that drawing as it has too many added parts to it. This is not a stock amp. Also, 67 is the JTM50 year. This is a very short lived amp as is the 784-128 OT.

Mac,

The 100V tap is the main difference in the 128 and yes, you can use a 139 to build a JTM50.

gibboau · Post by **gibboau** » Sat Feb 24, 2007 1:17 am

Thank you guys kindly for the all the info. I'll start my JMP50 once thats complete ill consider a JTM50

MacGaden · Post by **MacGaden** » Sat Feb 24, 2007 2:39 am

gibboau wrote:Thank you guys kindly for the all the info. I'll start my JMP50 once thats complete ill consider a JTM50

So you

gibboau · Post by **gibboau** » Sat Feb 24, 2007 3:22 am

Yes MacG i will be, ordering parts next week and i really cant wait to start the build.. i don't think you can go wrong with the stuff that George sells

MacGaden · Post by **MacGaden** » Sat Feb 24, 2007 3:38 am

Cool. For the sounds you prefer you might consider ordering extra caps, so you could turn it into a bass version, with shared cathode, 56k/pf tonestack, 0,1 output couplers.. Or something in between.

gibboau · Post by **gibboau** » Sat Feb 24, 2007 3:52 am

MacG, would you suggest a bass version over the lead? i was planning just to do the lead version... but ordering extra caps is a good idea just in case

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Tube Recto JMP 50

Tube Recto JMP 50

JTM50

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