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1976 2203 to superlead conversion

Posted: Mon Jun 19, 2006 9:36 pm
by Eric Klinger
Hi all. I think I am going to make the conversion. At the moment, I have the MV 100 watt ptp installed in my 1976 JMP 2203... I want to go with a superlead conversion.. Could I just buy the SL ptp kit from George and just install it (the current ptp 100watt will go in my 800 i think), or are there other parts needed... will my 2203 PT / OT / and choke work? are the pot values all the same? I know I'll at least need 2 more input jacks...

Also, I am searching around a bit, but not sure which circuit to get... 67? 68? 69? what are the major differences?

Thanks much!

Eric

Posted: Mon Jun 19, 2006 10:56 pm
by Eric Klinger
As usual, I couldn't wait to get something... so, I ordered a 69 circuit SL board kit, a prewired input jack and amp wiring kit.

Anyone know if I am missing something? I just placed the order for 2 day air, if I am missing, maybe I cab get a hold of George before he ships... here's exactly what I got...

1976 100 JMP MV (complete, I will use PT / OT / choke / tube sockets etc)
69 era SL board kit
full amp wiring kit
a few feet of Belden 2 cond coax
a prewired set of input jacks


Am I mising anything???

oh yes, and finally, how can I remove my face plate off of the JMP? I will probably buy some from George eventually, but that wont be for a few weeks.

Thanks.

Posted: Mon Jun 19, 2006 11:05 pm
by Flames1950
You don't have to use the extra jacks if you want to keep the original look (although the holes are already there on the chassis itself....) You can just jumper the grids on V1 and use the two volumes to mix the channels as if you had used a jumper cable on a four-hole amp. Otherwise you've got everything you need......you could have even reworked the PCB, it is the same board for a Super Lead, Super Bass or MV (and the same for the fifty watt versions as well.)

The faceplates don't come easy, the gunk Marshall used looked similar to extremely sticky two-sided tape. Be forewarned, you may very likely bend your original faceplate, making it valueless and useless and rendering the amp unrestorable to original.

Posted: Tue Jun 20, 2006 12:04 am
by Dax-The-Ax
Good luck, you are going to have to rely on Flames and the boys, Old Dax is a little Rusty!!

Posted: Tue Jun 20, 2006 12:12 am
by Eric Klinger
Thanks guys!
you could have even reworked the PCB, it is the same board for a Super Lead, Super Bass or MV (and the same for the fifty watt versions as well.)
I figured that... currently it has the 100 watt MV ptp board, I bought from George and installed about a year ago... so, I am thinking about putting that into my 1989 JCM 800... the layout is a bit different, so I suppose I will need to buy some new pots and drill a few holes in the chassis of the 800... if it's even possible - this 800 has, I think, 3 (?) filter caps... assuming I can do this and then find a diagram for it... ??

I suppose I could have used the original PCB from the '76 2203, but I like to play around with the resistors from time to time, I much prefer the PTP for that stuff.

Anyway, glad to hear such awesome news... can't wait to do it!

Posted: Tue Jun 20, 2006 12:26 am
by Necrovore
Get ahold of Guitar Adjuster. He is currently doing a late era 800 conversion to a PTP coversion like you are talking about. Sure he will be able to give you some advice.

Posted: Tue Jun 20, 2006 7:04 am
by Flames1950
Somewhere here I have a diagram of the changes and wiring for the three filter amps too. I'll scrounge around tonight -- just don't let me forget!

Posted: Thu Aug 31, 2006 9:21 pm
by RedHouse
Eric, do you still have the PCB that came in your 2203?
(please PM me if you do)