JTM100 build taking off! IT LIVES!

[C J H]

Hi,

It´s been a while since I posted here, more or less 5 years or so. Spent 4 of them in the swedish armed forces and I´m about to head home from my second tour in A-stan in a couple of days. Can´t wait!

Anyway when I left this forum last time I had plans of rebuilding my 10xxx series to "black flag specs" but they ended when I had to spend all my money replacing two blown G12h´s... Then I really haven´t played much guitar in the last 4 years, not nearly as much as I used to atleast. Thats all about to change, I´m putting my boots and beret in the basement for god! Civvy life here i come. That means some kind of college and lots of time to put into music.

So, ofcourse i revived my old plan of refurbishing my 10xxx SB build. It was built in 2005 using an alu-chassis from Georges first batch, 1203-80-ML PT and Metros 1202-132 OT. I´ve got some new boards on the way from Brian H and 8 47uF axial caps from a swedish source. I´ve had some other parts and a wire kit lying around back home since 2007 so the plan is to tidy up the build and really take my time doing it right while also going for something kinda odd.. Basically a JTM100 w a single rectifier.

I´ve been reading up on lost knowledge and just checking some other builds (bbeautiful ones!) on the forum during the past weeks. I´m catching up alright but still can´t really remeber how values adds up when wiring caps series or parallel and so on.. can´t remember which is which either. Therefore the filter/recto board is the only thing that still has some ? before I can get started. I´ve done two layouts (-- in paint, bare with me) and I would be very glad if someone could check them out as for correct values (23.5 PI ,23.5 SCREENS ,47 MAINS) and connections. I´ve chosen to wire it up the "safer" way with HV secs coming off the standby switch. Anyway, pics..

Thanks!
Jake

EDIT: Removed the faulty layout to avoid confusion.

[C J H]

.. God damnit.. where it says PT sec tap I mean PT common. I guess it´s time for bed.


EDIT: Yeah must a been relly tired. Not sec tap, not common it should say center tap!


Jake

[neikeel]

Bottom one is correct.

Two 47uF in parallel for approx 100uF in series with two more to give 50uF (approx) with PT centre tap to mid point of caps to evenly balance load, if period looks not important add a couple of 220k 2 watt (at least) MO fire proof resistors across them too.

[C J H]

Sweet!

Just to clarify, are these assumptions correct? Wiring series (+ >> -) gives yUf/x where y= capaciatance of the individual caps wired in series x= number of caps. As for my screensand PI, I have 2 47uF caps (y=47,x=2). They connect with one caps pos(+) end joining the others neg(-) end, this is "wired in series" right? 47/2= 23,5 uf

Parallell (+ >> +, - >> -) adds the values of the caps. So 2 47uF caps gives 94uF. Wiring two of these parallell sections in series (.. by adding the horizontal jumper between the mains filters for instance) basically means I´ve wired 2 94 uF caps in series and this gives (94/2=47uF), this is whats called series/parallell?

As I said, still trying to refresh some old knowledge
Thanks alot for your input Neil!

Jake

[neikeel]

Sweet!

Just to clarify, are these assumptions correct? Wiring series (+ >> -) gives yUf/x where y= capaciatance of the individual caps wired in series x= number of caps. As for my screensand PI, I have 2 47uF caps (y=47,x=2). They connect with one caps pos(+) end joining the others neg(-) end, this is "wired in series" right? 47/2= 23,5 uf

Parallell (+ >> +, - >> -) adds the values of the caps. So 2 47uF caps gives 94uF. Wiring two of these parallell sections in series (.. by adding the horizontal jumper between the mains filters for instance) basically means I´ve wired 2 94 uF caps in series and this gives (94/2=47uF), this is whats called series/parallell?

Yes correct.

[C J H]

.

[C J H]

Finished the cab today, the handles (Marshalls HW variant..) didnt fit to good so had to enlarge the holes a bit. They also differ a bit from the handles on my straight BW, I remeber those to have only 6 bolts/handle? The HW ones have eight.. anyway, no rattle but for looks/fit I will go with scumback handles if I do this on any other cabs in the future. Before I went to bed yesterday I soaked the grill with a spraybottle of water and now its REALLY tight and nice.



Also picked up some parts sourced locally in sweden and my order from valvestorm today. Great stuff! Pics will follow..

Jake

[C J H]

Alright, the new boards have arrived from Brian H and look flawless as usual!

I´ve wired up the filterboard and rectifer but thats all for now, will finish my JTM45 build before I tear down the Superbass.


New boards and some components


The JTM45 is coming along nicely, transformers will be here next week (Board is only in to check the fit.. )


-Jake

[axeman]

Nice

[julkke]

[axeman]

Were did you get the grill cloth? What style is it, hard to tell, I really like it.

[C J H]

Thanks, I got the grillcloth from a swedish vendor. Its regular 2tone basketweave ("salt n pepper")
http://gmf.jetshop.se/hogtalartyg-salt- ... -1145.aspx" onclick="window.open(this.href);return false;

-Jake

[axeman]

Good job keep us posted.

[C J H]

Alright, finished the JTM45 last week. It can be seen in its own thread. Today i started the teardown of my 100w and its transformation into a JTM100. Ripped pretty much everything from the amp, cleaned up the chassi and moved to holes to accomodate the screws for the bigger filterboard. I then mounted the panel, started bending leads and fitting components on the board. Lastly i flatlipped my headcab, might need a new frontbaffle for it, accidentally ripped the vinyl on one side of it.. oh well, otherwise I might make a relic ..



All for now!

[axeman]

Bad Ass, lets hear it.