Don't you love it when work, kids, gigs, minor tragedy take control of your life and it takes you over A YEAR to do a 20 min job?

Sat down with thesoldering iron a few days ago (up at 5am for some reason), and have installed the new transformer. Have the artificial centre tap installed, and the amp wired as per schematic

Have sat the VVR kit in place, and have done nothing else there. Have tested voltages with the amp on standby, getting 398 on the rectifier with no tube installed, 390 with a fat old RCA installed. Heaters are clocking in at 3.2v a piece, same for the pilot.

Have some JJ 6V6's handy and am about to test when my 19 mth old awakes.

Oh - message received loud and clear on the resistors! 100ohm resistrrs coming my way. I think I'll be grounding them at the same point as the cathode bias resistor - looks like an easy spot.

Cheers again - will be dropping by my local electronics shop to grab some resistors on the way home.

Yes - between the socket and the speaker out. The kit I purchased was everything mounted on an eyelet board, and the mosfet at a right angle, so thinking about here....picture telling a thousand words and all!
 


Simple 3 wire job to install (B+ in, b+ out and a ground). If I get brave, I'll try one in my AC30HH!

Hi Wyatt,

Thanks for the lengthy reply - I'm very, very thankful for it. I'm happy enough working on amps - I worked in IT tech for 12 or more year...back when CRT's were still common place. As a bloke that probably worked on 500 iMac's, I have great respect for voltage and it's ability to make your day worse...or life shorter! Never got bit by one, but did cop 240v fixing a tape backup unit in the early 1990's. I have massive respect for voltage.

I'll admit to being an amateur with the amp stuff - even when I started teching in 1990, IT stuff was sub-assembly replacement - but I do work on my own stable of amps. Over the weekend I gave my '73 Deluxe Reverb a cap job, and replaced the grid resistors in the PI section to hunt down a noise (ended up being the PI socket). I can drain the caps, and am comfortable with a soldering iron.

Great explanation on the center tap. I noted that these go to ground on the CTPT What rating resistors would you use? I have some 1w'ers in my stash (grid resistor stash!) - will they be okay? I too like the neatness of the Clark example.

I've had to carefully bend the tag on the standby switch to clear the "bell" on the bottom of the new PT. Haven't started soldering yet - was Daddy Daycare yesterday, had my older boys from 3pm and a quick practice for a gig tomorrow night. Might have a crack tonight.

If I can ask a supplementary, I purchased a VvR kit to go into this one to see how it worked. I'm thinking of mounting (looking at photo) the unit between the 5Y3's base and the 6V6, having the B+ from the standby into the board, then out to the rectifier. Can you see any problems with my idea here? I don't mind that the control is on the back.

Cheers Wyatt - that was my intention....honest!!

My transformer isn't the lowered version, but shares the same wiring codes as this one. I guess I'd be fine going with schematic only, but wanted a belt'n'braces approach. I'd be using the old pt as a reference to check I'd wired stuff up.

Tell me more about the artificial centre tap...I don't entirely understand.


Oh - should i just heatshrink the unused primary power taps? Individually, or as a large collective?

Guys,

I'm about to replace the PT in my 5E3 - in another thread I explained how the original PT was on its way out, and have gone with a heyboer replacement (a MOJO branded one). I've never replaced a PT before, but am confident I can do this!

My play is to clip the wires, leaving a small amount of wire and insulation from the original, remove old PT, bolt in new one, and use the old PT as a schematic of sorts - matching "purpose" from old PT with new.

Anyhting wrong with my plan? The new PT is slightly hotter - about 370v unloaded. Any considerations? I'm also putting in a VvR kit at some stage - after the filtered B+, but will get it up and running before I think about that.

Sorry for the tardy reply. An electrician friend of mine had a look and but his insulation tester over the amp. Secondaries are toast(ing), so new PT on the horizon. Thinking of trying a heybeor.

Thanks for all the help guys, much appreciated

Hi Nik,

My "Nik" comments were more a testimony to the neat build.

I'll have a look-see tomorrow - my elder boys are with my this weekend, so iron's away.

Cheers,

Andrew

Sleep dep? I have a 3 month old boy...I own sleep dep! 

Hey - nice idea mcinku - will do as soon as I can

PVB - I started tested with the rectifier (a cokebottle phillips) out....all tubes out, actually.

Hey - thanks for the reply.

no water - just high humidity - a western facing wall in an old house.

Has worked flawlessly til now - nice quiet amp. Photobucket for pics - can't work out how to post in forum.

HI All,

Sorry to be the guy that joins a forum, lurks, then hits people up with a question before being a part of the community, but I gots to be that guy.

I bought my deluxe off eBay after wanting one for a while. By the look of it, the amp could be a Nik build, and had been treated to SOZO mustards at some point. The board is more like a traditional fender board, not turreted....hmmm.  It's served me very well...until blowing a fuse on Monday. I figured that I should investigate what is going on - why the fuse blew.

So...with the tubes out, new fuse in (a 2a250V), I switched power on/standby at off, and no fuse blow...but the PT started to sizzle a little. Switched off, and there was a "not so nice" smell, and what I'm pretty sure was water splattered around the base of the PT (inside chassis). The room where I keep my stuff is a little damper than I'd like - somehting I've been addressing - so figured this might be part and parcel of the problem, so I gave the amp the night infront of the wood heater in my lounge - nice and warm.

Tried it this morning - not as bad, but a small wisp of smoke, and some water splatter.

I figured I should probably see what the collected wisdom of the forum to see where I should go from here? I'm not sure I can save the PT from this point, but figure I should try. Thank you all in advance